MODULATORS OF INDOLEAMINE 2,3-DIOXYGENASE

FIELD OF THE INVENTION

Compounds, methods and pharmaceutical compositions for the prevention and/or treatment of HIV; including the prevention of the progression of AIDS and general immunosuppression, by administering certain indoleamine 2,3-dioxygenase compounds in therapeutically effective amounts are disclosed. Methods for preparing such compounds and methods of using the compounds and pharmaceutical compositions thereof are also disclosed.

BACKGROUND OF THE INVENTION

lndoleamine-2,3-dioxygenase 1 (ID01) is a heme-containing enzyme that catalyzes the oxidation of the indole ring of tryptophan to produce N-formyl kynurenine, which is rapidly and constitutively converted to kynurenine (Kyn) and a series of downstream metabolites. ID01 is the rate limiting step of this kynurenine pathway of tryptophan metabolism and expression of ID01 is inducible in the context of inflammation. Stimuli that induce ID01 include viral or bacterial products, or inflammatory cytokines associated with infection, tumors, or sterile tissue damage. Kyn and several downstream metabolites are immunosuppressive: Kyn is antiproliferative and proapoptotic to T cells and NK cells (Munn, Shafizadeh et al. 1999, Frumento, Rotondo et al. 2002) while metabolites such as 3-hydroxy anthranilic acid (3-HAA) or the 3-HAA oxidative dimerization product cinnabarinic acid (CA) inhibit phagocyte function (Sekkai, Guittet et al. 1997), and induce the differentiation of immunosuppressive regulatory T cells (Treg) while inhibiting the differentiation of gut-protective IL-17 or IL-22 -producing CD4+ T cells (Th17 and Th22)(Favre, Mold et al. 2010). ID01 induction, among other mechanisms, is likely important in limiting immunopathology during active immune responses, in promoting the resolution of immune responses, and in promoting fetal tolerance. However in chronic settings, such as cancer, or chronic viral or bacterial infection, ID01 activity prevents clearance of tumor or pathogen and if activity is systemic, ID01 activity may result in systemic immune dysfunction (Boasso and Shearer 2008, Li, Huang et al. 2012). In addition to these immunomodulatory effects, metabolites of ID01 such as Kyn and quinolinic acid are also known to be neurotoxic and are observed to be elevated in several conditions of neurological dysfunction and depression. As such, ID01 is a therapeutic target for inhibition in a broad array of indications, such as to promote tumor clearance, enable clearance of intractable viral or bacterial infections, decrease systemic immune dysfunction manifest as persistent inflammation during HIV infection or

immunosuppression during sepsis, and prevent or reverse neurological conditions. IDQ1 and persistent inflammation in HIV Infection:

Despite the success of antiretroviral therapy (ART) in suppressing HIV replication and decreasing the incidence of AIDS-related conditions, HIV-infected patients on ART have a higher incidence of non-AIDS morbidities and mortality than their uninfected peers. These non-AIDS conditions include cancer, cardiovascular disease, osteoporosis, liver disease, kidney disease, frailty, and neurocognitive dysfunction (Deeks 2011 ). Several studies indicate that non-AIDS morbidity/mortality is associated with persistent inflammation, which remains elevated in HIV-infected patients on ART as compared to peers (Deeks 2011). As such, it is hypothesized that persistent inflammation and immune dysfunction despite virologic suppression with ART is a cause of these non-AIDS-defining events (NADEs).

HIV infects and kills CD4+ T cells, with particular preference for cells like those CD4+ T cells that reside in the lymphoid tissues of the mucosal surfaces (Mattapallil, Douek et al. 2005). The loss of these cells combined with the inflammatory response to infection result in a perturbed relationship between the host and all pathogens, including HIV itself, but extending to pre-existing or acquired viral infections, fungal infections, and resident bacteria in the skin and mucosal surfaces. This dysfunctional host:pathogen relationship results in the over-reaction of the host to what would typically be minor problems as well as permitting the outgrowth of pathogens among the microbiota. The dysfunctional host:pathogen interaction therefore results in increased inflammation, which in turn leads to deeper dysfunction, driving a vicious cycle. As inflammation is thought to drive non-AIDS morbidity/mortality, the mechanisms governing the altered host:pathogen interaction are therapeutic targets.

ID01 expression and activity are increased during untreated and treated HIV infection as well as in primate models of SIV infection (Boasso, Vaccari et al. 2007, Favre, Lederer et al. 2009, Byakwaga, Bourn et al. 2014, Hunt, Sinclair et al. 2014, Tenorio, Zheng et al. 2014). ID01 activity, as indicated by the ratio of plasma levels of enzyme substrate and product (Kyn/Tryp or K:T ratio), is associated with other markers of inflammation and is one of the strongest predictors of non-AIDS morbidity/mortality (Byakwaga, Bourn et al. 2014, Hunt, Sinclair et al. 2014, Tenorio, Zheng et al. 2014). In addition, features consistent with the expected impact of increased ID01 activity on the immune system are major features of HIV and SIV induced immune dysfunction, such as decreased T cell proliferative response to antigen and imbalance of Treg:Th17 in systemic and intestinal compartments (Favre, Lederer et al. 2009, Favre, Mold et al. 2010). As such, we and others hypothesize that ID01 plays a role in driving the vicious cycle of immune dysfunction and inflammation associated with non-AIDS morbidity/mortality. Thus, we propose that inhibiting ID01 will reduce inflammation and decrease the risk of NADEs in ART-suppressed HIV-infected persons. IDQ1 and Persistent Inflammation beyond HIV

As described above, inflammation associated with treated chronic HIV infection is a likely driver of multiple end organ diseases [Deeks 2011 ]. However, these end organ diseases are not unique to HIV infection and are in fact the common diseases of aging that occur at earlier ages in the HIV-infected population. In the uninfected general population inflammation of unknown etiology is a major correlate of morbidity and mortality [Pinti, 2016 #88]. Indeed many of the markers of inflammation are shared, such as IL-6 and CRP. If, as hypothesized above, ID01 contributes to persistent inflammation in the HIV-infected population by inducing immune dysfunction in the Gl tract or systemic tissues, then ID01 may also contribute to inflammation and therefore end organ diseases in the broader population. These inflammation associated end organ diseases are exemplified by cardiovascular diseases, metabolic syndrome, liver disease (NAFLD, NASH), kidney disease, osteoporosis, and neurocognitive impairment. Indeed, the ID01 pathway has links in the literature to liver disease (Vivoli abstracts at Italian Assoc. for the Study of the Liver Conference 2015], diabetes [Baban, 2010 #89], chronic kidney disease [Schefold, 2009 #90], cardiovascular disease [Mangge, 2014 #92;Mangge, 2014 #91 ], as well as general aging and all cause mortality [Pertovaara, 2006 #93]. As such, inhibition of ID01 may have application in decreasing inflammation in the general population to decrease the incidence of specific end organ diseases associated with inflammation and aging.

IDQ1 and Oncology

IDO expression can be detected in a number of human cancers (for example; melanoma, pancreatic, ovarian, AML, CRC, prostate and endometrial) and correlates with poor prognosis (Munn 2011). Multiple immunosuppressive roles have been ascribed to the action of IDO, including the induction of Treg differentiation and hyper-activation, suppression of Teff immune response, and decreased DC function, all of which impair immune recognition and promote tumor growth (Munn 2011). IDO expression in human brain tumors is correlated with reduced survival. Orthotropic and transgenic glioma mouse models demonstrate a correlation between reduced IDO expression and reduced Treg infiltration and a increased long term survival (Wainwright, Balyasnikova et al. 2012). In human melanoma a high proportion of tumors (33 of 36 cases) displayed elevated IDO suggesting an important role in establishing an immunosuppressive tumor

microenvironment (TME) characterized by the expansion, activation and recruitment of MDSCs in a Treg-dependent manner (Holmgaard, Zamarin et al. 2015). Additionally, host IDO expressing immune cells have been identified in the draining lymph nodes and in the tumors themselves (Mellor and Munn 2004). Hence, both tumor and host-derived IDO are believed to contribute to the immune suppressed state of the TME.

The inhibition of IDO was one of the first small molecule drug strategies proposed for re-establishment of an immunogenic response to cancer (Mellor and Munn 2004). The d-enantiomer of 1 -methyl tryptophan (D-1 MTor indoximod) was the first IDO inhibitor to enter clinical trials. While this compound clearly does inhibit the activity of IDO, it is a very weak inhibitor of the isolated enzyme and the in vivo mechanism(s) of action for this compound are still being elucidated. Investigators at Incyte optimized a hit compound obtained from a screening process into a potent and selective inhibitor with sufficient oral exposure to demonstrate a delay in tumor growth in a mouse melanoma model (Yue, Douty et al. 2009). Further development of this series led to INCB204360 which is a highly selective for inhibition of IDO-1 over IDO-2 and TDO in cell lines transiently transfected with either human or mouse enzymes (Liu, Shin et al. 2010). Similar potency was seen for cell lines and primary human tumors which endogenously express ID01 (IC50s ~ 3-20 nM). When tested in co-culture of DCs and naive CD4 ⁺ CD25 ^" T cells, INCB204360 blocked the conversion of these T cells into CD4 ⁺ FoxP3 ⁺ Tregs. Finally, when tested in a syngeneic model (PAN02 pancreatic cells) in immunocompetent mice, orally dosed INCB204360 provided a significant dose-dependent inhibition of tumor growth, but was without effect against the same tumor implanted in immune-deficient mice. Additional studies by the same investigators have shown a correlation of the inhibition of ID01 with the suppression of systemic kynurenine levels and inhibition of tumor growth in an additional syngeneic tumor model in immunocompetent mice. Based upon these preclinical studies, INCB24360 entered clinical trials for the treatment of metastatic melanoma (Beatty, O'Dwyer et al. 2013).

In light of the importance of the catabolism of tryptophan in the maintenance of immune suppression, it is not surprising that overexpression of a second tryptophan metabolizing enzyme, TD02, by multiple solid tumors (for example, bladder and liver carcinomas, melanomas) has also been detected. A survey of 104 human cell lines revealed 20/104 with TDO expression, 17/104 with ID01 and 16/104 expressing both (Pilotte, Larrieu et al. 2012). Similar to the inhibition of ID01 , the selective inhibition of TD02 is effective in reversing immune resistance in tumors overexpressing TD02 (Pilotte, Larrieu et al. 2012). These results support TD02 inhibition and/or dual TD02/ID01 inhibition as a viable therapeutic strategy to improve immune function.

Multiple pre-clinical studies have demonstrated significant, even synergistic, value in combining IDO-1 inhibitors in combination with T cell checkpoint modulating mAbs to CTLA-4, PD-1 , and GITR. In each case, both efficacy and related PD aspects of improved immune activity/function were observed in these studies across a variety of murine models (Balachandran, Cavnar et al. 2011 , Holmgaard, Zamarin et al. 2013, M. Mautino 2014, Wainwright, Chang et al. 2014). The Incyte ID01 inhibitor (INCB204360, epacadostat) has been clinically tested in combination with a CTLA4 blocker (ipilimumab), but it is unclear that an effective dose was achieved due to dose-limited adverse events seen with the combination. In contrast recently released data for an on-going trial combining epacadostat with Merck's PD-1 mAb (pembrolizumab) demonstrated improved tolerability of the combination allowing for higher doses of the ID01 inhibitor. There have been several clinical responses across various tumor types which is encouraging. However, it is not yet known if this combination is an improvement over the single agent activity of pembrolizumab (Gangadhar, Hamid et al. 2015). Similarly, Roche/Genentech are advancing NGL919/ GDC-0919 in combination with both mAbs for PD-L1 (MPDL3280A, Atezo) and OX-40 following the recent completion of a phase 1 a safety and PK/PD study in patients with advanced tumors. IDQ1 and chronic infections

ID01 activity generates kynurenine pathway metabolites such as Kyn and 3-HAA that impair at least T cell, NK cell, and macrophage activity (Munn, Shafizadeh et al. 1999, Frumento, Rotondo et al. 2002) (Sekkai, Guittet et al. 1997, Favre, Mold et al. 2010). Kyn levels or the Kyn/Tryp ratio are elevated in the setting of chronic HIV infection (Byakwaga, Bourn et al. 2014, Hunt, Sinclair et al. 2014, Tenorio, Zheng et al. 2014), HBV infection (Chen, Li et al. 2009), HCV infection (Larrea, Riezu-Boj et al. 2007, Asghar, Ashiq et al. 2015), and TB infection(Suzuki, Suda et al. 2012) and are associated with antigen-specific T cell dysfunction (Boasso, Herbeuval et al. 2007, Boasso, Hardy et al. 2008, Loughman and Hunstad 2012, Ito, Ando et al. 2014, Lepiller, Soulier et al. 2015). As such, it is thought that in these cases of chronic infection, ID01 -mediated inhibition of the pathogen- specific T cell response plays a role in the persistence of infection, and that inhibition of ID01 may have a benefit in promoting clearance and resolution of infection. IDQ1 and sepsis

ID01 expression and activity are observed to be elevated during sepsis and the degree of Kyn or Kyn/Tryp elevation corresponded to increased disease severity, including mortality (Tattevin, Monnier et al. 2010, Darcy, Davis et al. 2011). In animal models, blockade of ID01 or ID01 genetic knockouts protected mice from lethal doses of LPS or from mortality in the cecal ligation/puncture model (Jung, Lee et al. 2009, Hoshi, Osawa et al. 2014). Sepsis is characterized by an immunosuppressive phase in severe cases (Hotchkiss, Monneret et al. 2013), potentially indicating a role for ID01 as a mediator of immune dysfunction, and indicating that pharmacologic inhibition of ID01 may provide a clinical benefit in sepsis.

IDQ1 and neurological disorders

In addition to immunologic settings, ID01 activity is also linked to disease in neurological settings (reviewed in Lovelace Neuropharmacology 2016(Lovelace, Varney et al. 2016)). Kynurenine pathway metabolites such as 3-hydroxykynurenine and quinolinic acid are neurotoxic, but are balanced by alternative metabolites kynurenic acid or picolinic acid, which are neuroprotective. Neurodegenerative and psychiatric disorders in which kynurenine pathway metabolites have been demonstrated to be associated with disease include multiple sclerosis, motor neuron disorders such as amyotrophic lateral sclerosis, Huntington's disease, Parkinson's disease, Alzheimer's disease, major depressive disorder, schizophrenia, anorexia (Lovelace, Varney et al. 2016). Animal models of neurological disease have shown some impact of weak ID01 inhibitors such as 1 - methyltryptophan on disease, indicating that ID01 inhibition may provide clinical benefit in prevention or treatment of neurological and psychiatric disorders.

It would therefore be an advance in the art to discover IDO inhibitors that effective the balance of the aforementioned properties as a disease modifying therapy in chronic HIV infections to decrease the incidence of non-AIDS morbidity/mortality; and/or a disease modifying therapy to prevent mortality in sepsis; and/or an immunotherapy to enhance the immune response to HIV, HBV, HCV and other chronic viral infections, chronic bacterial infections, chronic fungal infections, and to tumors; and/or for the treatment of depression or other neurological/ neuropsychiatric disorders.

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SUMMARY OF THE INVENTION

Briefly, in one aspect, the present invention discloses compounds of Formula I

Formula I

or a pharmaceutically acceptable salt thereof wherein:

Q ¹ is C(0)0, C(0)CF ₂ , C(0)NH, S0 ₂ , C(O), or a bond (i.e. is absent);

Q ² is Ci- ₄ alkyl, Ci- ₃ alkylNHCi- ₃ alkyl, or a bond (i.e. is absent);

Q ³ is C(O), C(0)NH, or a bond (i.e. is absent);

R ¹ is Ci_6alkyl, C2-4alkenyl, C3-7cycloalkyl, Cs-garyl, Cs-gheteroaryl, or a 5 to 9 membered heterocycle; wherein R ¹ is optionally substituted with a substituent selected from Ci- ₆ alkyl, OCi- ₃ alkyl, OC ₃ - ₆ cycloalkyl, oxo, and N(R ² ) ₂ wherein each R ² is

independently H, Ci_ ₆ alkyl, C ₃ - ₇ cycloalkyl, Ci- ₃ alkylOCi- ₃ alkyl, -OCi- ₃ alkylOCi- ₃ alkyl C ₃ . ₆ cycloalkyl, -CH ₂ phenyl, or OCH ₂ phenyl;

R ³ is C ₅ -garyl, C ₅ -gheteroaryl, Ci_ ₆ alkyl, C ₃ . ₆ cycloalkyl, or C ₇ -iobicycloalkyl, wherein R ³ is optionally substituted with 1 or 2 substituents selected from halogen , Ci_6alkyl, Ci_ ₃ fluoroalkyl, C ₃ . ₆ cycloalkyl, OCi_ ₃ alkyl, SCi_ ₃ alkyl, C ₂ - ₄ alkenyl, C ₂ . alkynyl, OC ₂ . alkyny, phenyl, and CN;

R ⁴ is C ₅ -garyl, Ci_ ₆ alkyl, Ci- ₃ fluoroalkyl, C ₃ . ₆ cycloalkyl, C ₂ . alkenyl, C ₂ . alkynyl, or C ₃ .

₆ ether;

and wherein each aryl and heteroaryl includes bicycles and wherein each heteroaryl, and heterocycle contains from 1 to 3 heteroatoms selected from O, N, and S.

In another aspect, the present invention discloses pharmaceutical compositions comprising a compound of Formula I or a pharmaceutically acceptable salt thereof.

In another aspect, the present invention provides a compound of Formula I or a pharmaceutically acceptable salt thereof for use in therapy.

In another aspect, the present invention provides a compound of Formula I or a pharmaceutically acceptable salt thereof for use in treating diseases or conditions that would benefit from inhibition of IDO.

In another aspect, the present invention provides use of a compound of Formula I or a pharmaceutically acceptable salt thereof in the manufacture of a medicament for use in treating diseases or conditions that would benefit from inhibition of IDO.

In another aspect, the present invention discloses a method for treating a viral infection in a patient mediated at least in part by a virus in the retrovirus family of viruses, comprising administering to said patient a composition comprising a compound of Formula I , or a pharmaceutically acceptable salt thereof. In some embodiments, the viral infection is mediated by the HIV virus.

In another aspect, a particular embodiment of the present invention provides a method of treating a subject infected with H IV comprising administering to the subject a therapeutically effective amount of a compound of Formula I , or a pharmaceutically acceptable salt thereof.

In yet another aspect, a particular embodiment of the present invention provides a method of inhibiting progression of HIV infection in a subject at risk for infection with HIV comprising administering to the subject a therapeutically effective amount of a compound of Formula I , or a pharmaceutically acceptable salt thereof. Those and other embodiments are further described in the text that follows.

DETAILED DESCRIPTION OF REPRESENTATIVE EMBODIMENTS

Preferably Q ¹ is C(0)0, C(0)CF ₂ , C(0)NH, S0 ₂ , or C(O).

Preferably Q ² is absent.

Preferably Q ³ is C(O) .

Preferably R ¹ is phenyl, a pyridine, an oxadiazole, oxo substituted oxadiazole, Ci_ ₆ alkyl, C ₃ - ₇ cycloalkyl, C ₂ - ₄ alkenyl, or a 5 or 6-membered heterocycle containing one or two heteroatoms selected from O and N , wherein R ¹ is optionally substituted with a substituent selected from Ci_ ₆ alkyl, OCi- ₃ alkyl, OC ₃ - ₆ cycloalkyl, and N(R ² ) ₂ wherein each R ² is independently H, Ci-6alkyl, C3-7cycloalkyl Ci-3alkylOCi-3alkyl, -OCi-3alkylOCi-3alkyl C3- ₆ cycloalkyl, -CH ₂ phenyl, or OCH ₂ phenyl. More preferably, R ¹ is phenyl, a pyridine, an oxadiazole, Ci_ ₆ alkyl, C ₃ - ₇ cycloalkyl, or C ₂ . alkylenyl, wherein R ¹ is optionally substituted with a substituent selected from Ci_ ₆ alkyl, OCi- ₃ alkyl, and N(R ² ) ₂ wherein each R ² is independently Ci_ ₆ alkyl, or C ₃ - ₆ cycloalkyl.

Preferably R ³ is thiophene, phenyl, pyridyl, benzoxazole, oxazole, Ci_6alkyl, C3- 6cycloalkyl, or C7-iobicycloalkyl, wherein R ³ is optionally substituted with 1 or 2 substituents selected from halogen , Ci_ ₃ alkyl, Ci- ₃ fluoroalkyl, OCi- ₃ alkyl, SCi- ₃ alkyl, C ₂ . alkenyl, C ₂ . ₄ alkynyl, and OC ₂ . alkynyl. More preferably R ³ is thiophene or phenyl optionally substituted with 1 or 2 substituents selected from halogen, Ci_ ₃ alkyl, and C ₂ . ₃ alkynyl.

Preferably R ⁴ is phenyl, Ci_ ₆ alkyl, Ci- ₃ fluoroalkyl, C ₃ - ₆ cycloalkyl, C ₂ . alkynyl, or C ₃ - 6ether. More preferably R ⁴ is Ci-6alkyl.

Preferably the stereochemistry of the depicted carbon to which R ¹ -Q ² is bonded is as depicted below.

Preferred pharmaceutical compositions include unit dosage forms. Preferred unit dosage forms include tablets.

In particular, it is expected that the compounds and composition of this invention will be useful for prevention and/or treatment of H IV; including the prevention of the progression of AIDS and general immunosuppression . It is expected that in many cases such prevention and/or treatment will involve treating with the compounds of this invention in combination with at least one other drug thought to be useful for such prevention and/or treatment. For example, the IDO inhibitors of this invention may be used in combination with other immune therapies such as immune checkpoints (PD1 , CTLA4, ICOS, etc.) and possibly in combination with growth factors or cytokine therapies (IL21 , !L-7, etc.).

In is common practice in treatment of H IV to employ more than one effective agent. Therefore, in accordance with another embodiment of the present invention, there is provided a method for preventing or treating a viral infection in a mammal mediated at least in part by a virus in the retrovirus family of viruses which method comprises administering to a mammal, that has been diagnosed with said viral infection or is at risk of developing said viral infection, a compound as defined in Formula I , wherein said virus is an HIV virus and further comprising administration of a therapeutically effective amount of one or more agents active against an HIV virus, wherein said agent active against the HIV virus is selected from the group consisting of Nucleotide reverse transcriptase inhibitors; Non-nucleotide reverse transcriptase inhibitors; Protease inhibitors; Entry, attachment and fusion inhibitors; Integrase inhibitors; Maturation inhibitors; CXCR4 inhibitors; and CCR5 inhibitors. Examples of such additional agents are Dolutegravir, Bictegravir, and Cabotegravir. "Pharmaceutically acceptable salt" refers to pharmaceutically acceptable salts derived from a variety of organic and inorganic counter ions well known in the art and include, by way of example only, sodium, potassium, calcium, magnesium, ammonium, and tetraalkylammonium, and when the molecule contains a basic functionality, salts of organic or inorganic acids, such as hydrochloride, hydrobromide, tartrate, mesylate, acetate, maleate, and oxalate. Suitable salts include those described in P. Heinrich Stahl, Camille G. Wermuth (Eds.), Handbook of Pharmaceutical Salts Properties, Selection, and Use; 2002.

The present invention also includes pharmaceutically acceptable salts of the compounds described herein. As used herein, "pharmaceutically acceptable salts" refers to derivatives of the disclosed compounds wherein the parent compound is modified by converting an existing acid or base moiety to its salt form. Examples of pharmaceutically acceptable salts include, but are not limited to, mineral or organic acid salts of basic residues such as amines; alkali or organic salts of acidic residues such as carboxylic acids; and the like. The pharmaceutically acceptable salts of the present invention include the conventional non-toxic salts of the parent compound formed , for example, from nontoxic inorganic or organic acids. The pharmaceutically acceptable salts of the present invention can be synthesized from the parent compound which contains a basic or acidic moiety by conventional chemical methods. Generally, such salts can be prepared by reacting the free acid or base forms of these compounds with a stoichiometric amount of the appropriate base or acid in water or in an organic solvent, or in a mixture of the two; generally, nonaqueous media like ether, ethyl acetate, ethanol, isopropanol, or ACN are preferred.

The phrase "pharmaceutically acceptable" is employed herein to refer to those compounds, materials, compositions, and/or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation , allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.

In one embodiment, the pharmaceutical formulation containing a compound of Formula I or a salt thereof is a formulation adapted for oral or parenteral administration. In another embodiment, the formulation is a long-acting parenteral formulation. In a further embodiment, the formulation is a nano-particle formulation.

The present invention is directed to compounds, compositions and pharmaceutical compositions that have utility as novel treatments for immunosuppresion. While not wanting to be bound by any particular theory, it is thought that the present compounds are able to inhibit the enzyme that catalyzes the oxidative pyrrole ring cleavage reaction of I- Trp to /V-formylkynurenine utilizing molecular oxygen or reactive oxygen species.

Therefore, in another embodiment of the present invention, there is provided a method for the prevention and/or treatment of HIV; including the prevention of the progression of AIDS and general immunosuppression.

EXAMPLES

Compounds of the invention can be prepared by one skilled in the art according to the following general synthetic scheme.

PG = protecting group

CA = chiral auxilliary

X = halogen or other leaving group The following examples serve to more fully describe the manner of making and using the above-described invention. It is understood that these examples in no way serve to limit the true scope of the invention, but rather are presented for illustrative purposes. In the examples and the synthetic schemes below, the following abbreviations have the following meanings. If an abbreviation is not defined, it has its generally accepted meaning. abbreviation meaning

Boc tert-butoxycarbonyl

BOP benzotriazole-1 -yl-oxy-tris-(dimethylamino)-phosphonium

hexafluorophosphate

°C degrees Celsius

COMU (1 -cyano-2-ethoxy-2-oxoethylidenaminooxy)dimethylamino- morpholino-carbenium hexafluorophosphate

DBU 1 ,8-diazabicyclo[5.4.0]undec-7-ene

DCM dichloromethane

DEA diethylamine

DIEA N,N-diisopropylethylamine

DMAP 4-(dimethylamino)pyridine

DMF N,N-dimethylformamide

DMSO dimethylsulfoxide

ESI electrospray ionization

h or hr hours

HATU (1 -[bis(dimethylamino)methylene]-1 H-1 ,2,3-triazolo[4,5-b]pyridinium 3- oxid hexafluorophosphate)

HPLC high performance liquid chromatography

J coupling constant in Hz

LCMS liquid chromatography - mass spectrometry

M molar

mg milligram

min minute

mL milliliters

mM millimolar

mmol millimole

μΙ_ or uL microliters μΜ or uM micro molar

MS mass spectrum

N normal

NMR nuclear magnetic resonance

PE petroleum ether

ppm parts per million

PPTS pyridinium p-toluenesulfonate

RT room temperature

Rf retention factor

T3P propanephosphonic acid anhydride

TEA triethylamine

TFA trifluoroacetic acid

TFAA trifluoroacetic anhydride

THF tetrahydrofuran

TLC thin layer chromatography

Equipment Description

¹ H NMR spectra were recorded on a Varian 400 spectrometer. Chemical shifts are expressed in parts per million (ppm, δ units). Coupling constants are in units of hertz (Hz). Splitting patterns describe apparent multiplicities and are designated as s (singlet), d (doublet), t (triplet), q (quartet), quint (quintet), m (multiplet), br (broad).

The analytical low-resolution mass spectra (MS) were recorded on Waters ACQUITY UPLC with SQ Detectors using a Waters BEH C18, 2.1 x 50 mm, 1 .7 μηι using a gradient elution method. Solvent A: 0.1 % formic acid (FA) in water. Solvent B: 0.1 % FA in acetonitrile; 30% B for 0.5 min followed by 30-100% B over 2.5 min. Synthesis of amine intermediate tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1 - carbox late

Step 1 : Preparation of tert-butyl 4-(2-(methoxy(methyl)amino)-2-oxoethyl)piperidine-1 - carboxylate

To a stirred solution of 2-(1 -(tert-butoxycarbonyl)piperidin-4-yl)acetic acid (10.0 g, 41 .1 mmol), Ν,Ο-dimethylhydroxylamine hydrochloride (4.21 g, 43.2 mmol), and DIEA (21 .5 ml_, 123 mmol) in DMF (75 mL) at 0 °C was added 50% T3P/EtOAc (34.0 g, 53.4 mmol) by slow addition over 3 minutes. The resulting solution was stirred at 0 °C. After 2.5 hours the solution was partitioned between EtOAc and water and the phases separated. The aqueous phase was extracted with one additional portion of EtOAc. The combined EtOAc solutions were washed with 10% aqueous citric acid (2x), saturated aqueous NaHC0 ₃ (2x), dried over Na ₂ S0 ₄ , and concentrated to dryness at reduced pressure to give the title compound as a colorless oil (9.16 g, 78% yield).

LCMS (ESI) m/z calcd for C14H26N2O4: 286.2. Found: 287.4 (M+1 ) ⁺ . Ή NMR (400 MHz, CDC ) δ 4.07 (d, J = 13.2 Hz, 2H), 3.67 (s, 3H), 3.18 (s, 3H), 2.73 (t, J = 12.9 Hz, 2H), 2.35 (d, J = 6.4 Hz, 2H), 1 .93 - 2.10 (m, 1 H), 1 .71 (d, J = 12.8 Hz, 2H), 1 .45 (s, 9H), 1 .08 - 1 .21 (m, 2H). Step 2: Preparation of tert-butyl 4- 2-oxo-2-phenylethyl)piperidine-1 -carboxylate

To a stirred solution of tert-butyl 4-(2-(methoxy(methyl)amino)-2-oxoethyl)piperidine-1 - carboxylate (9.13 g, 31 .9 mmol) in anhydrous THF (106 mL) at 0 °C was added 1 M PhMgBr (38.3 mL, 38.3 mmol) by dropwise addition. After 10 minutes the solution was allowed to warm to RT. After 2 hours the solution was quenched by addition of saturated NH ₄ CI. The resulting mixture was partitioned between water and EtOAc and the phases separated. The aqueous phase was extracted with EtOAc (2x). The combined EtOAc solutions were washed with water (1 x), saturated brine (1x), dried over Na ₂ S0 ₄ and concentrated at reduced. The residue was subjected to flash chromatography (silica gel, 0-50% EtOAc/hexanes, gradient elution) to afford the title compound as a white crystalline solid (9.04 g, 93% yield). LCMS (ESI) m/z calcd for C18H25NO3: 303.2. Found: 204.2 (M+1 -Boc) ⁺ . ¹ H NMR (400 MHz, CDC ) δ

7.95 (d, J = 7.3 Hz, 2H), 7.53 - 7.61 (m, 1 H), 7.41 - 7.52 (m, 2H), 4.09 (d, J = 13.2 Hz, 2H), 2.90 (d, J = 6.6 Hz, 2H), 2.70 - 2.81 (m, 2H), 2.06 - 2.25 (m, 1 H), 1 .75 (d, J = 12.6 Hz, 2 H), 1 .46 (s, 9H), 1 .13 - 1 .27 (m, 2H).

Step 3: Preparation of tert-butyl 4-(2-(hydroxyimino)-2-phenylethyl)piperidine-1 - carboxylate

A solution of tert-butyl 4-(2-oxo-2-phenylethyl)piperidine-1 -carboxylate (3.40 g, 11 .2 mmol), NaOAc (4.60 g, 56.0 mmol), and hydroxylamine hydrochloride (1 .56 g, 22.4 mmol) in 2:1 EtOH/H ₂ 0 (80 mL) was stirred at 90 °C for 3 hours and then cooled to RT. The solution was partitioned between EtOAc and water and the phases separated. The aqueous phase was extracted with two additional portions of EtOAc. The combined EtOAc solutions were washed with brine (1x), dried over Na ₂ S0 ₄ and concentrated at reduced pressure to give the title compound as a white crystalline solid (3.52 g, 99% yield). LCMS (ESI) m/z calcd for C18H26N2O3: 318.2. Found: 319.4 (M+1) ⁺ . ¹ H NMR (400 MHz, CDC ) δ 7.56 - 7.65 (m, 2H), 7.33 - 7.46 (m, 3H), 4.04 (br s, 2H), 2.81 (d, J = 7.3 Hz, 2H), 2.63 (t, J = 12.1 Hz, 2H), 1 .75 - 1 .87 (m, 1 H), 1 .64 (d, J = 13.0 Hz, 2H), 1 .45 (s, 9H), 1 .14 - 1 .33 (m, 2H). Step 4: Preparation of tert-butyl 4- 2-amino-2-phenylethyl)piperidine-1 -carboxylate

A solution of tert-butyl 4-(2-(hydroxyimino)-2-phenylethyl)piperidine-1 -carboxylate (3.52 g, 1 1 .1 mmol) in MeOH (75 ml_) was subjected to hydrogenation at 60 psi in the presence of 10% Pd/C (0.25 g). After 18 hours the reaction vessel was purged with nitrogen, catalyst removed by filtration, and the filtrate concentrated at reduced pressure to give the title compound as a colorless oil (3.35 g, 100%). LCMS (ESI) m/z calcd for Ci ₈ H28N ₂ 02: 304.2. Found: 305.4 (M+1) ⁺ . Ή NMR (400 MHz, CDCI ₃ ) δ 7.20 - 7.38 (m, 5H), 3.87 - 4.18 (m, 3H), 2.55 - 2.70 (m, 2H), 1 .51 - 1 .88 (m, 6H), 1 .34 - 1 .49 (m, 10H), 0.99 - 1 .21 (m, 2H).

Example 1 : tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-2-phenylethyl)piperidi ne- 1 -carboxylate

To a stirred solution of tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1 -carboxylate (50.0 mg, 0.164 mmol), 5-ethylthiophene-2-carboxylic acid (28.2 mg, 0.181 mmol), and DIEA (86 uL ml_, 0.49 mmol) in DMF (2 mL) was added HATU (94 mg, 0.25 mmol). The resulting solution was stirred at RT. After 18 hours the solution was treated with 2M ammonia/MeOH (3 mL). After stirring at RT for an additional 1 hour, the solution was partitioned between EtOAc and brine and the phases separated. The EtOAc solution was washed with 10% aqueous citric acid (2x), saturated aqueous NaHC0 ₃ (2x), dried over Na ₂ S0 ₄ , and concentrated to dryness at reduced pressure. The residue was subjected to flash chromatography (silica gel, 0-100% EtOAc/hexanes, gradient elution) to afford the title compound as a white solid (54 mg, 74% yield). LCMS (ESI) m/z calcd for C25H34N2O3S: 442.2. Found: 465.3 (M+Na) ⁺ . ¹ H NMR (400 MHz, CDCI ₃ ) δ 7.28 - 7.45 (m, 6H), 6.80 (d, J = 3.5 Hz, 1 H), 6.03 (d, J = 8.3 Hz, 1 H), 5.22 - 5.37 (m, 1 H), 4.09 (br s, 2H), 2.89 (q, J = 7.4 Hz, 2H), 2.67 (t, J = 12.5 Hz, 2H), 1 .69 - 1 .98 (m, 4H), 1 .42 - 1 .55 (m, 10H), 1 .35 (t, J = 7.6 Hz, 3 H), 1 .10 - 1 .30 (m, 2H).

Example 2: tert-butyl 4-(2-(5-bromothiophene-2-carboxamido)-2-phenylethyl)piperidi ne- 1 -carboxylate

The title compound was prepared in 77% yield from tert-butyl 4-(2-amino-2- phenylethyl)piperidine-1 -carboxylate and 5-bromothiophene-2-carboxylic acid as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2- carboxamido)-2-phenylethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C ₂₃ H ₂₉ BrN ₂ 0 ₃ S: 492.1 . Found: 493.2 (M+1) ⁺ . Ή NMR (400 MHz, CDCI ₃ ) δ 7.27 - 7.40 (m, 5H), 7.20 (d, J = 3.9 Hz, 1 H), 7.01 (d, J = 3.9 Hz, 1 H), 6.01 (d, J = 8.2 Hz, 1 H), 5.22 (q, J = 8.2 Hz, 1 H), 3.95 - 4.10 (m, 2H), 2.61 (t, J = 12.3 Hz, 2H), 1 .65 - 1 .94 (m, 4H), 1 .35 - 1 .50 (m, 10H), 1 .01 - 1 .30 (m, 2H). Example 3: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-phenylethyl)piperid ine- 1 -carboxylate

To a stirred solution of tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1 -carboxylate (0.785 g, 2.58 mmol) in DMF (30 mL) was added COMU (1 .63 g, 3.81 mmol) followed by DIEA (1 .36 mL, 7.79 mmol) and then 5-chlorothiophene-2-carboxylic acid (0.544 g, 3.35 mmol). After stirring at RT for 2 hours, the solution was quenched with water and partitioned between DCM and saturated aqueous Na ₂ C0 ₃ . The phases were separated and the aqueous phase extracted with DCM (2x). The combined DCM solutions were concentrated to dryness at reduced pressure and the residue purified by reverse phase HPLC (C18, MeCN/water with ammonium carbonate modifier) to afford the title compound. LCMS (ESI) m/z calcd for C23H29CIN2O3S: 448.1 . Found: 449.1 (M+1) ⁺ . ¹ H NMR (400 MHz, CDCI ₃ ) δ 7.22 - 7.44 (m, 6H), 6.90 (d, J = 4.0 Hz, 1 H), 6.00 (d, J = 8.1 Hz, 1 H), 5.25 (q, J = 8.1 Hz, 1 H), 4.07 (br s, 2H), 2.58 - 2.71 (m, 2H), 1 .69 - 1 .96 (m, 4H), 1 .38 - 1 .53 (m, 10H), 1 .07 - 1 .34 (m, 2H).

Example 4: tert-butyl 4-(2-(5-ethynylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

Step 1 : Preparation of tert-butyl 4-(2-phenyl-2-(5-((trimethylsilyl)ethynyl)thiophene-2- carboxamido)ethyl)piperidine-1-carbox late

A stirred solution of tert-butyl 4-(2-(5-bromothiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate (76 mg, 0.15 mmol),

tetrakis(triphenylphosphine)palladium(0) (18 mg, 0.015 mmol), and copper(l) iodide (2.9 mg, 0.015 mmol) in THF (3 ml_) was sparged with nitrogen for 5 minutes, and then treated with TEA (0.107 ml_, 0.770 mmol) followed by TMS-acetylene (0.107 ml_, 0.770 mmol). The resulting solution was heated to 85 °C in a sealed vessel. After 30 minutes LCMS indicated complete reaction. The mixture was cooled to RT, filtered to removed solids, and the filtrate concentrated to dryness at reduced pressure. The residue was subjected to flash chromatography (silica gel, 0-100% EtOAc/hexanes, gradient elution) to afford the title compound as a light yellow foam (68 mg, 86%). LCMS (ESI) m/z calcd for C28H38N2O3SS1: 510.2. Found: 51 1 .4 (M+1 ) ⁺ .

Step 2: Preparation of tert-butyl 4-(2-(5-ethynylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

To a stirred solution of tert-butyl 4-(2-phenyl-2-(5-((trimethylsilyl)ethynyl)thiophene-2- carboxamido)ethyl)piperidine-1 -carboxylate (68 mg, 0.13 mmol) in MeOH (3 mL) was added K ₂ C0 ₃ (92 mg, 0.67 mmol). The resulting mixture was stirred at RT. After 1 hour the mixture was partitioned between EtOAc and 10% aqueous citric acid and the phases separated. The EtOAc solution was washed with saturated aqueous NaHC0 ₃ (2x), dried over Na ₂ S0 ₄ and concentrated at reduced pressure. The residue was subjected to flash chromatography (silica gel, 0-100% EtOAc/hexanes, gradient elution) to afford the title compound as a white solid (42 mg, 72% yield). LCMS (ESI) m/z calcd for C25H30N2O3S: 438.2. Found: 439.3 (M+1) ⁺ . ¹ H NMR (400 MHz, CDC ) δ 7.26 - 7.40 (m, 6H), 7.18 (d, J = 3.9 Hz, 1 H), 6.09 (d, J = 8.2 Hz, 1 H), 5.24 (q, J = 7.8 Hz, 1 H), 4.04 (br s, 2H), 3.42 (s, 1 H), 2.54 - 2.68 (m, 2H), 1 .66 - 1 .95 (m, 4H), 1 .37 - 1 .50 (m, 10H), 1 .02 - 1 .30 (m, 2H).

Example 5: tert-butyl 4-(2-(4-ethynylbenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Step 1 : Preparation of tert-butyl 4-(2-(4-bromobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

The title compound was prepared in 85% yield from tert-butyl 4-(2-amino-2- phenylethyl)piperidine-1 -carboxylate and 4-bromobenzoic acid as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C25H ₃ iBrN20 ₃ : 486.2. Found: 487.2 (M+1) ⁺ . Ή NMR (400 MHz, CDCI ₃ ) δ 7.52 - 7.65 (m, 4 H), 7.23 - 7.40 (m, 5H), 6.21 (d, J= 8.2 Hz, 1H), 5.23 - 5.33 (m, 1H), 3.97 - 4.10 (m, 2H), 2.53 - 2H), 1.66 - 1.95 (m, 4H), 1.36 - 1.48 (m, 10H), 1.07 - 1.29 (m, 2H).

Steps 2 and 3: Preparation of tert-butyl 4-(2-(4-ethynylbenzamido)-2- phenylethyl)piperidine-1-carboxylate

The title compound was prepared in two steps in 31% overall yield from tert-butyl 4-(2- (4-bromobenzamido)-2-phenylethyl)piperidine-1-carboxylate as described herein for the preparation of tert-butyl 4-(2-(5-ethynylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1-carboxylate. LCMS (ESI) m/z calcd for C27H32N2O3: 432.2. Found: 433.3 (M+1) ⁺ . ¹ H NMR (400 MHz, CDCI ₃ ) δ 7.68 (d, J = 8.2 Hz, 2H), 7.51 (d, J = 8.2 Hz, 2H), 7.25 - 7.38 (m, 5H), 6.21 (d, J = 7.8 Hz, 1 H), 5.28 (q, J = 7.8 Hz, 1 H), 4.03 (brs, 2H), 3.17 (s, 1H), 2.53-2.66 (m, 2H), 1.63- 1.95 (m, 4H), 1.35- 1.46 (m, 10H), 0.98- 1.27 (m, 2H).

Example 6: tert-butyl 4-(2-(4-ethynyl-3-fluorobenzamido)-2-phenylethyl)piperidine- 1 - carbox late

Step 1 : Preparation of tert-butyl 4-(2-(4-bromo-3-fluorobenzamido)-2- phenylethyl)piperidine-1 -carboxylate

The title compound was prepared in 82% yield from tert-butyl 4-(2-amino-2- phenylethyl)piperidine-1 -carboxylate and 4-bromo-3-fluorobenzoic acid as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C25H3oBrFN ₂ 0 ₃ : 504.1 . Found: 505.3 (M+1) ⁺ . ¹ H NMR (400 MHz, CDCI ₃ ) δ 7.60 (dd, J = 8.2, 6.6 Hz, 1 H), 7.52 (dd, J = 9.0, 2.0 Hz, 1 H), 7.27 - 7.41 (m, 6H), 6.24 (d, J = 8.2 Hz, 1 H), 5.21 - 5.31 (m, 1 H), 3.99 - 4.09 (m, 2H), 2.54 - 2.66 (m, 2H), 1 .66 - 1 .93 (m, 4H), 1 .34 - 1 .47 (m, 10H), 1 .06 - 1 .29 (m, 2H). Steps 2 and 3: Preparation of tert-butyl 4-(2-(4-ethynyl-3-fluorobenzamido)-2- phenylethyl)piperidine-1 -carboxylate

The title compound was prepared in two steps in 57% overall yield from tert-butyl 4-(2- (4-bromo-3-fluorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

as described herein for the preparation of tert-butyl 4-(2-(5-ethynylthiophene-2- carboxamido)-2-phenylethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C27H31 FN2O3: 450.2. Found: 451 .3 (M+1 ) ⁺ . Ή NMR (400 MHz, CDCI ₃ ) δ 7.43 - 7.57 (m, 3H), 7.27 - 7.42 (m, 5H), 6.25 (d, J = 8.2 Hz, 1 H), 5.27 (q, J = 7.8 Hz, 1 H), 4.05 (br s, 2H), 3.41 (s, 1 H), 2.53 - 2.67 (m, 2H), 1 .65 - 1 .96 (m, 4H), 1 .34 - 1 .52 (m, 10H), 1 .03 - 1 .31 (m, 2H).

Example 7: ethyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-cyclopropylethyl)pi peridine- 1 -carboxylate

o

Step 1 : Preparation of tert-butyl 4-(2-cyclopropyl-2-oxoethyl)piperidine-1 -carboxylate

To a solution of tert-butyl 4-(2-(methoxy(methyl)amino)-2-oxoethyl)piperidine-1 - carboxylate (13.4 g, 46.9 mmol) in THF (200 mL) -78 °C, was slowly added a solution of 1 M cyclopropylmagnesium bromide in THF (141 mL, 141 mmol). After stirring at RT overnight, the reaction was quenched with saturated aqueous NH ₄ CI and extracted with EtOAc. The organic layer was washed with brine, dried over Na ₂ S0 ₄ , filtered and concentrated to give the crude product which was purified by flash chromatography (silica gel, 0-15% EtOAc in PE, gradient elution) to afford the title compound (9.0 g, 72% yield). LCMS (ESI) m/z calcd for C15H25NO3: 267.2. Found: 268.3 (M+1 ) ⁺ .

Step 2: Preparation of tert-butyl 4- 2-amino-2-cyclopropylethyl)piperidine-1 -carboxylate

To a solution of tert-butyl 4-(2-cyclopropyl-2-oxoethyl)piperidine-1 -carboxylate (500 mg, 1 .87 mmol) in MeOH (8 mL), was added NH ₄ OAc (2.88 g, 37.3 mmol) and NaBH ₃ CN (1 .18 mg, 18.7 mmol) successively. After stirring at RT overnight, the reaction was quenched with saturated aqueous NH ₄ CI and extracted with EtOAc. The organic layer was washed with brine, dried over Na ₂ S0 ₄ , filtered and concentrated to give the title compound (510 mg, quantitative yield), which was used in the following step without purificaton. LCMS (ESI) m/z calcd for C15H28N2O2: 268.2. Found: 269.4 (M+1) ⁺ . Step 3: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate

To a solution of tert-butyl 4-(2-amino-2-cyclopropylethyl)piperidine-1 -carboxylate (502 mg, 1 .87 mmol) in DMF (8 mL), was added 5-chlorothiophene-2-carboxylic acid (365 mg, 2.24 mmol), DIEA (1 .13 mL, 6.48 mmol) and HATU (853 mg, 2.24 mmol) successively. After stirring at RT for 3 hours, the reaction was diluted with water and extracted with EtOAc. The organic layer was washed with brine, dried over Na2S04, filtered and concentrated to give the crude product which was purified by flash chromatography (silica gel, 0-20% EtOAc in PE, gradient elution) to afford the title compound (650 mg, 84% yield). LCMS (ESI) m/z calcd for C20H29CIN2O3S: 412.2. Found: 413.7 (M+1) ⁺ .

Step 4: Preparation of 5-chloro-N-(1 -cyclopropyl-2-(piperidin-4-yl)ethyl)thiophene-2- carboxamide hydrochloride

To a solution of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate (200 mg, 0.35 mmol) in DCM (2 mL), was added 4 M HCI in dioxane (3 mL) dropwise. After stirring at RT for 2 hours, the reaction mixture was concentrated to afford the title compound (220 mg, 100% yield), which was used in the following step without purification. LCMS (ESI) m/z calcd for Ci ₅ H ₂ iCIN ₂ OS: 312.1 . Found: 313.7 (M+1) ⁺ Step 5: Preparation of ethyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl) piperidine-1 -carbox late

To a solution of 5-chloro-N-(1 -cyclopropyl-2-(piperidin-4-yl)ethyl)thiophene-2- carboxamide (140 mg, 0.448 mmol), DIEA (0.37 mL, 2.24 mmol) in DCM (2 mL) at 0 °C, was added ethyl chloroformate (0.13 mL, 1 .34 mmol) dropwise. After stirring at RT for 2 hours, the reaction was quenched with saturated aqueous NaHC0 ₃ solution and extracted with EtOAc. The organic layer was washed with brine, dried over Na ₂ S0 ₄ , filtered and concentrated to give the crude product which was purified by flash chromatography (silica gel, 0-20% EtOAc in PE, gradient elution) to afford the title compound (93 mg, 54% yield). LCMS (ESI) m/z calcd for C18H25CIN2O3S: 384.1 .

Found: 385.3 (M+1) ⁺ . Ή NMR (400 MHz, DMSO-c/ ₆ ) δ 8.34 (d, J = 8.8 Hz, 1 H), 7.68 (d, J = 4.1 Hz, 1 H), 7.17 (d, J = 4.0 Hz, 1 H), 4.00 (q, J = 7.1 Hz, 2H), 3.95 - 3.81 (m, 2H), 3.47 - 3.38 (m, 1 H), 2.79 - 2.58 (m, 2H), 1 .72 - 1 .54 (m, 3H), 1 .52 - 1 .42 (m, 2H), 1 .15 (t, J = 7.1 Hz, 3H), 1 .10 - 0.99 (m, 1 H), 0.98 - 0.86 (m, 2H), 0.50 - 0.42 (m, 1 H), 0.39 - 0.32 (m, 1 H), 0.31 - 0.23 (m, 1 H), 0.21 - 0.13 (m, 1 H).

Synthesis of intermediate (S)-tert-butyl 4-(2-amino-2-cyclopropylethyl)piperidine-1 - carboxylate hydrochloride

Step 1 : Preparation of (S,E)-tert-butyl 4-(2-((tert-butylsulfinyl)imino)ethyl)piperidine-1 - carboxylate

To a solution of (S)-2-methylpropane-2-sulfinamide (1 .76 g, 14.5 mmol) in DCM (36 mL) was added PPTS (0.166 g, 0.660 mmol) and magnesium sulfate (3.97 g, 33.0 mmol) followed by N-Boc-piperidineacetaldehyde (3.00 g, 13.2 mmol) and the mixture was stirred at ambient temperature for 18 hours. The mixture was filtered and the filtrate concentrated. The material was subjected to flash chromatography (silica gel, dry loading, 0-40% EtOAc/hexanes, gradient elution) to provide the title compound (4.04 g, 93 % yield) as an off-white solid. LCMS (ESI) m/z calcd for Ci ₆ H ₃ oN ₂ S: 330.2. Found: 331 .4 (M+1) ⁺ . Ή NMR (400 MHz, CDCI ₃ ) δ 8.05 (t, J = 4.9 Hz, 1 H), 4.07 (br s, 2H), 2.70 (t, J = 12.1 Hz, 2H), 2.41 - 2.53 (m, 2H), 1 .91 (ddd, J = 1 1 .0, 7.3, 3.9 Hz, 1 H), 1 .64 - 1 .77 (m, 3H), 1 .44 (s, 9H), 1 .1 1 - 1 .27 (m, 10H). Step 2: Preparation of tert-butyl 4-((S)-2-cyclopropyl-2-((S)-1 ,1 - dimethylethylsulfinamido) ethyl)piperidine-1 -carboxylate

To a solution of tert-butyl (S,E)-4-(2-((tert-butylsulfinyl)imino)ethyl)piperidine-1 - carboxylate (1 .60 g, 4.84 mmol) in DCM (120 mL) at ambient temperature under a nitrogen atmosphere was added dropwise in 10 minutes 0.5M cyclopropylmagnesium bromide/THF (10.7 mL, 5.33 mmol). After stirring for 1 hour, saturated NH ₄ CI/water was added and the mixture was extracted with DCM. The organic phase was washed with water, brine, dried (Na ₂ S0 ₄ ), concentrated and dried in vacuo to provide a thick oil. The material was subjected to flash chromatography (silica gel, dry loading, 0-20% acetone/hexanes, gradient elution) to provide the title compound

(0.88 g, 49 % yield). LCMS (ESI) m/z calcd for C19H36N2O3S: 372.2. Found: 373.4 (M+1) ⁺ . Ή NMR (400 MHz, CDCI ₃ ) δ 4.07 (br s, 2H), 3.12 (br s, 1 H), 2.57 - 2.78 (m, 2H), 2.50 (d, J = 6.3 Hz, 1 H), 1 .52 - 1 .76 (m, 6H), 1 .44 (s, 9H), 1 .21 (s, 9H), 1 .02-1 .15 (m, 1 H), 0.77 - 0.93 (m, 1 H), 0.54 - 0.67 (m, 2H), 0.42 (dd, J = 9.0, 4.7 Hz, 1 H), 0.19 - 0.31 (m, 1 H).

Step 3: Preparation of (S)-tert-butyl 4-(2-amino-2-cyclopropylethyl)piperidine-1 - carboxylate hydrochloride

To a solution of 4-((S)-2-cyclopropyl-2-((S)-1 ,1 -dimethylethylsulfinamido)

ethyl)piperidine-1 -carboxylate (550 mg, 1 .48 mmol) in MeOH (8.5 mL) was added 4M HCI/dioxane (0.369 mL, 1 .48 mmol) and the mixture was stirred at ambient temperature for 30 minutes. The mixture was concentrated and the resulting pale yellow solid was dried in vacuo to provide the title compound (450 mg, 95 % yield) as on off-white solid. LCMS (ESI) m/z calcd for C15H28N2O2: 268.2. Found: 269.4 (M+1 ) ⁺ . Ή NMR (400 MHz, DMSO-c/e) δ 7.90 (br s, 3H), 3.89 (d, J = 10.5 Hz, 2H), 2.65 (br s, 2H), 1 .44 - 1 .74 (m, 5H), 1 .36 (s, 9H), 0.75 - 1 .00 (m, 3H), 0.53 - 0.62 (m, 1 H), 0.46 - 0.52 (m, 1 H), 0.42 (dd, J=9.4, 4.7 Hz, 1 H), 0.23 - 0.34 (m, 1 H).

Example 8: (S)-tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine- -carboxylate

To a suspension of tert-butyl (S)-4-(2-amino-2-cyclopropylethyl)piperidine-1 -carboxylate hydrochloride (30 mg, 0.1 12 mmol) in EtOAc (1 .5 mL) was added 5-chlorothiophene-2- carboxylic acid (20.0 mg, 0.123 mmol), DIEA (0.078 mL, 0.45 mmol) and 50%

T3P/EtOAc (78 mg, 0.123 mmol). The mixture was stirred at ambient temperature for 18 hours then diluted with EtOAc and the solution washed with water. The organic phase was dried (Na ₂ S0 ₄ ), concentrated and the residue subjected to flash

chromatography (silica gel, dry loading, 0-30% EtOAc/hexanes, gradient elution) to provide the title compound (12 mg, 26%) as a solid foam. LCMS (ESI) m/z calcd for C20H29CIN2O3S: 412.2. Found: 413.3 (M+1 ) ⁺ . ¹ H NMR (400 MHz, CDCI ₃ ) δ 7.22 (d, J = 3.9 Hz, 1 H), 6.88 (d, J = 3.9 Hz, 1 H), 5.64 (d, J = 8.9 Hz, 1 H), 4.03 (d, J = 12.1 Hz, 2H), 3.42 - 3.65 (m, 1 H), 2.54 - 2.73 (m, 2H), 1 .78 (d, J = 13.3 Hz, 1 H), 1 .47 - 1 .65 (m, 4H), 1 .42 (s, 9H), 0.98 - 1 .33 (m, 1 H), 0.75 - 0.92 (m, 2H), 0.51 - 0.64 (m, 1 H), 0.35 - 0.50 (m, 2H), 0.27 (dt, J = 9.5, 4.8 Hz, 1 H). Example 9: (S)-tert-butyl 4-(2-cyclopropyl-2-(5-methylthiophene-2- carboxamido)ethyl)piperidi -1-carboxylate

The title compound was prepared from tert-butyl (S)-4-(2-amino-2- cyclopropylethyl)piperidine-1 -carboxylate hydrochloride and 5-methylthiophene-2- carboxylic acid as described herein for the synthesis of (S)-tert-butyl 4-(2-(5- chlorothiophene-2-carboxamido)-2-cyclopropylethyl)piperidine -1 -carboxylate. LCMS (ESI) m/z calcd for C21 H32N2O3S: 392.2. Found: 393.3 (M+1 ) ⁺ . ¹ H NMR (400 MHz, CDC ) δ 7.30 (d, J = 3.5 Hz, 1 H), 6.74 (d, J = 3.5 Hz, 1 H), 5.67 (d, J = 9.0 Hz, 1 H), 4.04 (d, J = 12.9 Hz, 2H), 3.59 (t, J = 7.2 Hz, 1 H), 2.64 (t, J = 12.9 Hz, 2H), 2.51 (s, 3H), 1 .81 (d, J = 13.3 Hz, 1 H), 1 .50 - 1 .66 (m, 6H), 1 .44 (s, 9H), 0.77 - 0.91 (m, 1 H), 0.50 - 0.61 (m, 1 H), 0.37 - 0.50 (m, 2H), 0.28 (dt, J = 9.1 , 4.6 Hz, 1 H).

Example 10: (S)-tert-butyl 4-(2-cyclopropyl-2-(5-ethylthiophene-2- carboxamido)ethyl)piperidine-1 -carboxylate

The title compound was prepared from tert-butyl (S)-4-(2-amino-2- cyclopropylethyl)piperidine-1 -carboxylate hydrochloride and 5-ethylthiophene-2- carboxylic acid as described herein for the synthesis of (S)-tert-butyl 4-(2-(5- chlorothiophene-2-carboxamido)-2-cyclopropylethyl)piperidine -1 -carboxylate. LCMS (ESI) m/z calcd for C22H34N2O3S: 406.2. Found: 407.4 (M+1 ) ⁺ . ¹ H NMR (400 MHz, CDCb) δ 7.33 (d, J = 3.5 Hz, 1 H), 6.77 (d, J = 3.1 Hz, 1 H), 5.67 (d, J = 9.0 Hz, 1 H), 4.04 (d, J = 12.9 Hz, 2H), 3.60 (t, J = 7.2 Hz, 1 H), 2.86 (q, J = 7.7 Hz, 2H), 2.65 (t, J 12.9 Hz, 2H), 1.82 (d, J = 12.9 Hz, 1 H), 1.51 - 1 .66 (m, 6H), 1.44 (s, 9H), 1 .32 (t, J = 7.6 Hz, 3H), 0.77 - 0.91 (m, 1 H), 0.50 - 0.61 (m, 1 H), 0.37 - 0.49 (m, 2H), 0.28 (dt, J = 9.2, 4.8 Hz, 1 H). Example 11 : (S)-ethyl 4-(2-cyclopropyl-2-(5-methylthiophene-2- carboxamido)ethyl)piperidine-1-carboxylate

The title compound was prepared in two steps from (S)-tert-butyl 4-(2-cyclopropyl-2-(5- methylthiophene-2-carboxamido)ethyl)piperidine-1-carboxylate as described herein for the preparation of ethyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine-1-carboxylate. LCMS (ESI) m/z calcd for C19H28N2O3S: 364.2. Found: 365.3 (M+1). Ή NMR (400 MHz, CDCI ₃ ) δ 7.30 (d, J = 3.1 Hz, 1 H), 6.74 (d, J = 3.1 Hz, 1 H), 5.66 (d, J = 8.9 Hz, 1 H), 4.10 (q, J = 7.0 Hz, 4H), 3.50 - 3.67 (m, 1 H), 2.70 (t, J = 12.7 Hz, 2H), 2.51 (s, 3H), 1.84 (d, J = 12.9 Hz, 1 H), 1.51 - 1.67 (m, 5H), 1.24 (t, J = 6.8 Hz, 3H), 0.99 - 1.20 (m, 1 H), 0.75 - 0.93 (m, 1 H), 0.51 - 0.62 (m, 1 H), 0.36 - 0.49 (m, 2H), 0.28 (dt, J = 9.1 , 4.6 Hz, 1 H).

Example 12: ethyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate

Step 1 : Preparation of (S)-5-chloro-N-(1 -cyclopropyl-2-(piperidin-4-yl)ethyl)thiophene-2- carboxamide hydrochloride

To a solution of fe/ -butyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate (40 mg, 0.097 mmol) in DCM (0.5 ml_) was added 4 M HCI in dioxane (1 .0 ml_). After stirred at RT for 1 hour, the reaction mixture was concentrated under vacuum to afford the title compound (35 mg, 100% yield) as an HCI salt, which was used in the following step directly. LCMS (ESI) m/z calcd for

C15H21CIN2OS: 312.1 . Found: 313.2 (M+1) ⁺ . Step 2: Preparation of ethyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate

To a stirred solution of (S)-5-chloro-N-(1 -cyclopropyl-2-(piperidin-4-yl)ethyl)thiophene-2- carboxamide hydrochloride (35 mg, 0.097 mmol) in DCM (1 ml_) at 0 °C was added DIEA (50 mg, 0.38 mmol) followed by ethyl chloroformate (31 mg, 0.29 mmol). After stirring at RT for 2 hours, the reaction mixture was partitioned between DCM and water, and the layers were separated. The organic layer was washed with aqueous NaHC0 ₃ , brine, and dried over Na ₂ S0 ₄ . Solvent was removed under vacuum and the residue was purified by reverse phase HPLC (C18, 10-50% MeCN in water with 0.1 % formic acid) to afford the title compound (16 mg, 43% yield) as a white solid. LCMS (ESI) m/z calcd for Ci ₈ H25CIN20 ₃ S: 384.1 . Found: 385.2 (M+1 ) ⁺ . Ή NMR (400 MHz, DMSO-c/ ₆ ) δ 8.34 (d, J = 8.9 Hz, 1 H), 7.68 (d, J = 4.1 Hz, 1 H), 7.17 (d, J = 4.0 Hz, 1 H), 4.00 (q, J = 7.1 Hz, 2H), 3.95 - 3.85 (m, 2H), 3.46 - 3.38 (m, 1 H), 2.76 - 2.58 (m, 2H), 1 .71 - 1 .54 (m, 3H), 1 .51 - 1 .43 (m, 2H), 1 .15 (t, J = 7.1 Hz, 3H), 1 .09 - 1 .00 (m, 1 H), 0.97 - 0.87 (m, 2H), 0.50 - 0.42 (m, 1 H), 0.38 - 0.25 (m, 2H), 0.20 - 0.13 (m, 1 H).

Example 13: (S)-methyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine-1 -carboxylate

The title compound was prepared from (S)-5-chloro-N-(1 -cyclopropyl-2-(piperidin-4- yl)ethyl)thiophene-2-carboxamide hydrochloride and methyl chloroformate in 50% yield as desribed herein for the synthesis of ethyl (S)-4-(2-(5-chlorothiophene-2- carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C17H23CIN2O3S: 370.1 . Found: 371 .3 (M+1 ) ⁺ . ¹ H NMR (400 MHz, DMSO-c/ ₆ ) δ 8.34 (d, J = 8.8 Hz, 1 H), 7.68 (d, J = 4.1 Hz, 1 H), 7.17 (d, J = 4.0 Hz, 1 H), 3.98 - 3.82 (m, 2H), 3.56 (s, 3H), 3.46 - 3.38 (m, 1 H), 2.78 - 2.58 (m, 2H), 1 .73 - 1 .41 (m, 5H), 1 .10 - 0.87 (m, 3H), 0.50 - 0.41 (m, 1 H), 0.39 - 0.24 (m, 2H), 0.21 - 0.13 (m, 1 H). Example 14: isopropyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine-1 -carboxylate

The title compound was prepared from (S)-5-chloro-N-(1 -cyclopropyl-2-(piperidin-4- yl)ethyl)thiophene-2-carboxamide hydrochloride and isopropyl chloroformate in 40% yield as desribed herein for the synthesis of ethyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)- 2-cyclopropyl ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C19H27CIN2O3S: 398.1 . Found: 399.3 (M+1) ⁺ . ¹ H NMR (400 MHz, DMSO-c/ ₆ ) δ 8.34 (d, J = 8.8 Hz, 1 H), 7.68 (d, J = 4.0 Hz, 1 H), 7.17 (d, J = 4.0 Hz, 1 H), 4.78 - 4.67 (m, 1 H), 4.00 - 3.81 (m, 2H), 3.47 - 3.37 (m, 1 H), 2.79 - 2.58 (m, 2H), 1 .71 - 1 .43 (m, 5H), 1 .16 (d, J = 6.2 Hz, 6H), 1 .08 - 0.89 (m, 3H), 0.50 - 0.42 (m, 1 H), 0.39 - 0.24 (m, 2H), 0.21 - 0.14 (m, 1 H).

Example 15: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(6-methoxypyridin-3 - yl)ethyl)piperidine-1 -carboxylate

Stepl : Preparation of tert-butyl 4-(2-(6-methoxypyridin-3-yl)-2-oxoethyl)piperidine-1 - carboxylate

A solution of 5-bromo-2-methoxypyridine (0.55 ml, 4.25 mmol) in THF (10 ml) was cooled to -78 °C, treated dropwise with 2.5M nBuLi /hexanes (1 .70 ml, 4.25 mmol), and stirred at the same temperature for 1 hour. The reaction was treated slowly with a solution of tert- butyl 4-(2-(methoxy(methyl)amino)-2-oxoethyl)piperidine-1 -carboxylate (1 .00 g, 3.49 mmol) in THF (10 ml), and stirred for 1 hour while letting the bath slowly warm up. The bath was removed, and the reaction was stirred at RT for 15 minutes. The mixture was quenched with saturated NH4CI, extracted with EtOAc, washed with brine, dried over

Na ₂ S0 ₄ , filtered, and concentrated. Purification by flash chromatography (silica gel, 0-70% EtOAc/hexanes, gradient elution) afforded the title compound (0.94 g, 80 % yield) as light yellow oil that slowly crystallized. LCMS (ESI) m/z calcd for C18H26N2O4: 334.2. Found: 357.4 (M+23) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 8.78 (d, J = 2.2 Hz, 1 H), 8.14 (dd, J = 2.5, 8.7 Hz, 1 H), 6.80 (d, J = 8.6 Hz, 1 H), 4.18 - 3.96 (m, 5H), 2.83 (d, J = 6.8 Hz, 2H), 2.75 (t, J = 12.1 Hz, 2H), 2.22 - 2.08 (m, 1 H), 1 .73 (d, J = 13.0 Hz, 2H), 1 .46 (s, 9H), 1 .31 - 1 .12 (m, 2H).

Step 2: Preparation of tert-butyl 4-(2-amino-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 - carboxylate formic acid salt

A solution of tert-butyl 4-(2-(6-methoxypyridin-3-yl)-2-oxoethyl)piperidine-1 -carboxylate (0.314 g, 0.939 mmol) in 2M ammonia /EtOH (7 mL, 14.0 mmol) was treated with titanium(IV) isopropoxide (1 .10 mL, 3.76 mmol) and stirred at RT in a screw cap tube. After 18 hours, the reaction was treated with additional titanium(IV) isopropoxide (0.55 mL), stirred at RT for 1 hour, and then heated at 65 °C for 1 hour. The reaction was cooled to 0 °C, treated with NaBH ₄ (53.3 mg, 1 .41 mmol) and stirred at RT for 18 hours. The mixture was poured to aqueous NH ₄ OH, diluted with EtOH, and stirred for 20 minutes at RT. The suspension was filtered and washed with EtOH, and then EtOAc. The filtrate was concentrated, the residue was diluted with water, extracted with EtOAc, washed with brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by reverse phase flash chromatography (ISCO C18 column, 5-55% MeCN/water with 0.1 % formic acid) afforded the title compound as the formic acid salt (261 mg, 73 % yield) as white solid. LCMS (ESI) m/z calcd for CieHzgNsOs: 335.2. Found: 336.4 (M+1) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 8.50 (br s, 1 H), 8.23 (d, J = 2.4 Hz, 1 H), 7.78 (dd, J = 2.5, 8.7 Hz, 1 H), 6.90 (d, J = 8.8 Hz, 1 H), 4.39 (dd, J = 5.7, 10.1 Hz, 1 H), 4.02 (t, J = 14.6 Hz, 2H), 3.93 (s, 3H), 2.78 - 2.48 (m, 2H), 2.02 - 1 .81 (m, 2H), 1 .76 (d, J = 12.6 Hz, 1 H), 1 .61 (d, J = 13.9 Hz, 1 H), 1 .52 - 1 .38 (m, 9H), 1 .37 - 1 .23 (m, 1 H), 1 .22 - 1 .03 (m, 2H).

Step 3: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(6- methoxypyridin-3-yl)ethyl)pi eridine-1 -carboxylate

A suspension of tert-butyl 4-(2-amino-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 - carboxylate formic acid salt (30 mg, 0.079 mmol) in DMF (1 mL) was treated with 5- chlorothiophene-2-carboxylic acid (15.3 mg, 0.094 mmol), DIEA (0.048 mL, 0.275 mmol) HATU (36 mg, 0.094 mmol), and stirred at RT for 2 hours. The reaction was treated with additional DIEA (50 uL), HATU (36 mg), and stirred at RT for another 45 minutes. The mixture was diluted with water, extracted with EtOAc, washed with water, brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by reverse phase HPLC (C18, 15-100% MeCN/water with 0.1 % formic acid) afforded the title compound (12 mg, 31 % yield) as a white solid. LCMS (ESI) m/z calcd for C23H30CIN3O4S: 479.2. Found: 478.5 (M-1 )v Ή NMR (400MHz, DMSO-c/e) δ 8.84 (d, J = 8.4 Hz, 1 H), 8.14 (d, J = 2.2 Hz, 1 H), 7.79 - 7.65 (m, 2H), 7.19 (d, J = 4.0 Hz, 1 H), 6.80 (d, J = 8.4 Hz, 1 H), 5.08 - 4.94 (m, 1 H), 3.97 - 3.85 (m, 2H), 3.82 (s, 3H), 2.74 - 2.55 (m, 2H), 1 .92 - 1 .76 (m, 1 H), 1 .72 - 1 .57 (m, 3H), 1 .49 - 1 .32 (m, 10H), 1 .13 - 0.92 (m, 2H). Example 16: tert-butyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2-(6-methoxypyrid in-3- yl)ethyl)piperidine-1 -carbox late

The title compound (white solid) was prepared in 52% yield from tert-butyl (S)-4-(2-amino- 2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate and 5-chlorothiophene-2- carboxylic acid as described herein for the preparation of tert-butyl (S)-4-(2-(4- bromobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C23H30CIN3O4S: 479.2. Found: 480.3 (M+1 ) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 8.17 (br s, 1 H), 7.56 (d, J = 8.2 Hz, 1 H), 7.24 (br. s., 1 H), 6.89 (br s, 1 H), 6.75 (d, J = 8.4 Hz, 1 H), 6.01 (d, J = 7.5 Hz, 1 H), 5.19 (q, J = 7.1 Hz, 1 H), 4.21 - 3.99 (m, 2H), 3.93 (s, 3H), 2.74 - 2.50 (m, 2H), 1 .99 - 1 .65 (m, 4H), 1 .55 - 1 .33 (m, 10H), 1 .30 - 1 .05 (m, 2H). Example 17: tert-butyl (S)-4-(2-(4-fluorobenzamido)-2-(6-methoxypyridin-3- yl)ethyl)piperidine-1 -carbox late

The title compound (white solid) was prepared in 36% yield from tert-butyl (S)-4-(2-amino- 2-(6-methoxypyridin-3-yl)ethyl)piperidine-1-carboxylate and 4-fluorobenzoic acid as described herein for the preparation of tert-butyl (S)-4-(2-(4-bromobenzamido)-2-(6- methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C25H32FN3O4: 457.2. Found: 458.4 (M+1) ⁺ . ¹ H NMR (400MHz, CDCI3) δ 8.19 (br s, 1 H), 7.83 - 7.68 (m, 2H), 7.59 (dd, J = 1.7, 8.3 Hz, 1 H), 7.11 (t, J = 8.4 Hz, 2H), 6.75 (d, J = 8.4 Hz, 1 H), 6.20 (d, J = 7.7 Hz, 1 H), 5.25 (q, J = 7.6 Hz, 1 H), 4.17 - 3.99 (m, 2H), 3.93 (s, 3H), 2.78 - 2.50 (m, 2H), 1 .97 - 1 .66 (m, 4H), 1 .53 - 1.36 (m, 10H), 1.32 - 1 .07 (m, 2H).

Example 18: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-4-methylpentyl)piperi dine- 1-carboxylate

The title compound (white solid) was prepared in 4 steps from tert-butyl 4-(2- (methoxy(methyl)amino)-2-oxoethyl)piperidine-1 -carboxylate and isobutylmagnesium bromide as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2- carboxamido)-2-phenylethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for

C21 H33CIN2O3S: 428.2. Found: 451 .3 (M+23) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 7.23 (d, J = 3.9 Hz, 1 H), 6.90 (d, J = 3.9 Hz, 1 H), 5.43 (d, J = 9.4 Hz, 1 H), 4.37 - 4.22 (m, 1 H), 4.20 - 3.92 (m, 2H), 2.80 - 2.54 (m, 2H), 1 .88 (d, J = 12.5 Hz, 1 H), 1 .72 - 1 .54 (m, 1 H), 1 .54 - 1 .25 (m, 15H), 1 .22 - 1 .00 (m, 2H), 0.99 - 0.85 (m, 6H). Example 19: tert-butyl (S)-4-(2-(4-chlorobenzamido)-2-(6-methoxypyridin-3- yl)ethyl)piperidine-1 -carbox late

The title compound (white solid) was prepared in 31 % yield from tert-butyl (S)-4-(2-amino- 2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate formic acid salt and 4- chlorobenzoic acid as described herein for the preparation of tert-butyl (S)-4-(2-(4- bromobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C25H32CIN3O4: 473.2. Found: 474.4 (M+1 ) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 8.19 (d, J = 2.3 Hz, 1 H), 7.68 (d, J = 8.6 Hz, 2H), 7.58 (dd, J = 2.3, 8.6 Hz, 1 H), 7.40 (d, J = 8.6 Hz, 2H), 6.75 (d, J = 8.6 Hz, 1 H), 6.21 (d, J = 7.8 Hz, 1 H), 5.25 (q, J = 7.8 Hz, 1 H), 4.20 - 3.99 (m, 2H), 3.93 (s, 3H), 2.71 - 2.51 (m, 2H), 1 .96 - 1 .67 (m, 4H), 1 .53 - 1 .34 (m, 10H), 1 .30 - 1 .08 (m, 2H). Example 20: tert-butyl (S)-4-(2-(6-methoxypyridin-3-yl)-2-(5-methylthiophene-2- carboxamido)ethyl)piperidine-1 -carbox late

A mixture of tert-butyl (S)-4-(2-amino-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 - carboxylate formic acid salt (50 mg, 0.131 mmol) and 5-methylthiophene-2-carboxylic acid (28.0 mg, 0.197 mmol) in DMF (1 .3 mL) was treated with DIEA (0.069 ml_, 0.393 mmol), and then 50% T3P/EtOAc (0.117 mL, 0.197 mmol) slowly. After stirring for 4 hours at RT, the reaction was diluted with water and extracted with EtOAc. The EtOAc solution was washed with 1 N HCI, saturated aqueous NaHC0 ₃ , water, brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by reverse phase HPLC (20-90% MeCN/water with 0.1 % formic acid) afforded the titled compound (6.7 mg, 11 % yield) as white solid. LCMS (ESI) m/z calcd for C24H33N3O4S: 459.2. Found: 460.3 (M+1 ) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 8.17 (d, J = 2.3 Hz, 1 H), 7.57 (dd, J = 2.3, 8.6 Hz, 1 H), 7.30 (d, J = 3.5 Hz, 1 H), 6.78 - 6.69 (m, 2H), 5.93 (d, J = 7.8 Hz, 1 H), 5.21 (q, J = 7.8 Hz, 1 H), 4.19 - 3.97 (m, 2H), 3.93 (s, 3H), 2.74 - 2.55 (m, 2H), 2.51 (s, 3H), 1 .94 - 1 .67 (m, 4H), 1 .53 - 1 .36 (m, 10H), 1 .30 - 1 .07 (m, 2H).

Example 21 : isopropyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2-(6-methoxypyrid in-3- yl)ethyl)piperidine-1 -carbox late

The title compound was prepared in 86% yield from tert-butyl (S)-4-(2-(5-chlorothiophene- 2-carboxamido)-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate and isopropyl chloroformate as described herein for the preparation of phenyl (R)-4-(2-(5- chlorothiophene-2-carboxamido)propyl)piperidine-1-carboxylat e. LCMS (ESI) m/z calcd for C22H28CIN3O4S: 465.2. Found: 466.3 (M+1) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 8.17 (br s, 1 H), 7.56 (d, J = 7.8 Hz, 1 H), 7.24 (br s, 1 H), 6.89 (br s, 1 H), 6.75 (d, J = 8.6 Hz, 1 H), 6.03 (d, J = 7.0 Hz, 1 H), 5.28 - 5.09 (m, 1 H), 4.99 - 4.76 (m, 1 H), 4.32 - 4.01 (m, 2H), 3.93 (br s, 3H), 2.80 - 2.50 (m, 2H), 1 .93 - 1.67 (m, 4H), 1 .42 (br s, 1 H), 1 .33 - 1.03 (m, 8H).

Example 22: isopropyl (S)-4-(2-(4-chlorobenzamido)-2-(6-methoxypyridin-3- yl)ethyl)piperidine-1 -carbox late

The title compound was prepared in 69% yield from tert-butyl (S)-4-(2-(4- chlorobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate and isopropyl chloroformate as described herein for the preparation of phenyl (R)-4-(2-(5- chlorothiophene-2-carboxamido)propyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C24H30CIN3O4: 459.2. Found: 460.3 (M+1) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 8.19 (s, 1 H), 7.68 (d, J = 8.2 Hz, 2H), 7.58 (dd, J = 2.0, 8.6 Hz, 1 H), 7.40 (d, J = 8.6 Hz, 2H), 6.75 (d, J = 8.6 Hz, 1 H), 6.22 (d, J = 7.8 Hz, 1 H), 5.24 (q, J = 7.8 Hz, 1 H), 4.97 - 4.79 (m, 1 H), 4.27 - 4.01 (m, 2H), 3.93 (s, 3H), 2.77 - 2.54 (m, 2H), 1 .96 - 1 .68 (m, 4H), 1.52 - 1 .36 (m, 1 H), 1.32 - 1.09 (m, 8H).

Synthesis of amine intermediate (S)-tert-butyl 4-(2-amino-2-(6-methoxypyridin-3- yl)eth l)piperidine-1 -carboxylate

Step 1 : Preparation of tert-butyl 4-((S)-2-(((S)-1 -(4-methoxyphenyl)ethyl)amino)-2-(6- methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate

A suspension of tert-butyl 4-(2-(6-methoxypyridin-3-yl)-2-oxoethyl)piperidine-1 -carboxylate (3.00 g, 8.97 mmol) and (S)-1 -(4-methoxyphenyl)ethan-1 -amine (2.00 mL, 13.5 mmol) in titanium(IV) isopropoxide (7.89 mL, 26.9 mmol) was stirred at 90 °C. The reaction progress was monitored by LCMS (aliquots treated with MeOH, NaBH ₄ , followed by 1 N HCI). LCMS indicated complete reaction after 1 hour. The yellow solution was cooled to 0 °C, diluted with MeOH (15 mL), treated slowly with NaBH ₄ (0.509 g, 13.46 mmol) in portions. After 1 hour, the solution was warmed to RT and stirred for an additional 4 hours.. The reaction was quenched with saturated aqueous NH ₄ CI and 1 N HCI and then extracted with EtOAc. The EtOAc solution was washed with saturated aqueous NaHC0 ₃ , brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. ¹ H-NMR analysis of the crude material showed an approximately 2:1 mixture of SS : RS diastereomers. Purification by flash chromatography (silica gel, 0-100% EtOAc/hexanes, gradient elution) afforded tert- butyl 4-((S)-2-(((S)-1 -(4-methoxyphenyl)ethyl)amino)-2-(6-methoxypyridin-3- yl)ethyl)piperidine-1 -carboxylate (2.39 g, 57% yield) as clear oil. LCMS (ESI) m/z calcd for C27H39N3O4: 469.3. Found: 470.4 (M+1) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 7.85 (s, 1 H), 7.48 (d, J = 8.6 Hz, 1 H), 7.12 (d, J = 8.2 Hz, 2H), 6.87 (d, J = 8.2 Hz, 2H), 6.76 (d, J = 8.6 Hz, 1 H), 4.08 - 3.88 (m, 5H), 3.82 (s, 3H), 3.40 (q, J = 6.4 Hz, 1 H), 3.33 (t, J = 6.6 Hz, 1 H), 2.67 - 2.43 (m, 2H), 1 .66 - 1 .48 (m, 2H), 1 .47 - 1 .16 (m, 15H), 1 .09 - 0.82 (m, 2H).

Step 2: Preparation of tert-butyl (S)-4-(2-amino-2-(6-methoxypyridin-3-yl)ethyl)piperidine- 1 -carboxylate

A solution of tert-butyl 4-((S)-2-(((S)-1 -(4-methoxyphenyl)ethyl)amino)-2-(6- methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate (2.38 g, 5.07 mmol) in MeOH (51 ml) under N ₂ was treated with 10% Pd/C (0.81 g). The mixture was subjected to

hydrogenation at 60 psi and 60 °C for 18 hours. After cooling to RT, the mixture was purged with N ₂ , filtered, washed with MeOH, and concentrated. The crude product was purified by flash chromatography (silica gel, 0-10% MeOH containing 1 % NH ₄ OH /DCM, gradient elution) to give the title compound (1 .08 g, 64 % yield) as clear oil. Chiral analytical HPLC indicated an enantiomeric purity of 95% [Chiralcel OZ-H column

(4.6mm x 250mm, 5μ); mobile phase: 3:7 EtOH/hexane +0.1 % DEA; flow rate: 1 mL/min; injection volume: 6uL (1 mg/mL cone); monitored at 254 nm]. LCMS (ESI) m/z calcd for Ci ₈ H29N30 ₃ : 335.2. Found: 358.4 (M+23) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 8.12 (d, J = 2.0 Hz, 1 H), 7.74 (dd, J = 2.3, 8.6 Hz, 1 H), 6.83 (d, J = 8.6 Hz, 1 H), 4.12 (t, J = 7.6 Hz, 1 H), 4.07 - 3.93 (m, 2H), 3.90 (s, 3H), 2.65 (br. s., 2H), 1 .80 - 1 .66 (m, 3H), 1 .66 - 1 .54 (m, 1 H), 1 .43 (s, 9H), 1 .38 - 1 .24 (m, 1 H), 1 .17 - 1 .01 (m, 2H). Example 23: tert-butyl (S)-4-(2-(4-bromobenzamido)-2-(6-methoxypyridin-3- yl)ethyl)piperidine-1 -carboxylate

A solution of tert-butyl (S)-4-(2-amino-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 - carboxylate (50 mg, 0.149 mmol) in DMF (1 .5 mL) was treated with 4-bromobenzoic acid (33.0 mg, 0.164 mmol), DIEA (0.078 mL, 0.447 mmol), HATU (85 mg, 0.224 mmol), and stirred at RT for 2 hours. The reaction was quenched with 2M NH ₃ /MeOH and stirred for an additional 1 .5 hours. The mixture was diluted with water and extracted with EtOAc. The EtOAc solution was washed with 1 N HCI, saturated aqueous NaHC0 ₃ , brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by reverse phase HPLC (C18, 20- 90% MeCN/water with 0.1 % formic acid) afforded the title compound (60 mg, 77 % yield) as white solid. LCMS (ESI) m/z calcd for C25H ₃ 2BrN ₃ 04: 517.2. Found: 518.3 (M+1) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 8.19 (d, J = 1 .6 Hz, 1 H), 7.69 - 7.48 (m, 5H), 6.75 (d, J = 8.6 Hz, 1 H), 6.22 (d, J = 7.8 Hz, 1 H), 5.24 (q, J = 7.7 Hz, 1 H), 4.25 - 3.98 (m, 2H), 3.93 (s, 3H), 2.74 - 2.48 (m, 2H), 1 .96 - 1 .68 (m, 4H), 1 .53 - 1 .34 (m, 10H), 1 .31 - 1 .06 (m, 2H).

Example 24: tert-butyl (S)-4-(2-(5-ethylthiophene-2-carboxamido)-2-(6-methoxypyridi n-3- yl)ethyl)piperidine-1 -carboxylate

The title compound (white solid) was prepared in 89% yield from tert-butyl (S)-4-(2-amino- 2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate and 5-ethylthiophene-2-carboxylic acid as described herein for the preparation of tert-butyl (S)-4-(2-(4-bromobenzamido)-2- (6-methoxypyridin-3-yl)ethyl)piperidine-1-carboxylate. LCMS (ESI) m/z calcd for C25H35N3O4S: 473.2. Found: 474.3 (M+1) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 8.17 (d, J = 2.0 Hz, 1 H), 7.57 (dd, J = 2.1 , 8.4 Hz, 1 H), 7.33 (d, J = 3.5 Hz, 1 H), 6.81 - 6.68 (m, 2H), 5.96 (d, J = 8.2 Hz, 1 H), 5.22 (q, J = 7.8 Hz, 1 H), 4.25 - 3.99 (m, 2H), 3.93 (s, 3H), 2.86 (q, J = 7.4 Hz, 2H), 2.73 - 2.51 (m, 2H), 1 .93 - 1 .68 (m, 4H), 1.54 - 1.38 (m, 10H), 1.32 (t, J = 7.6 Hz, 3H), 1 .28 - 1.06 (m, 2H).

Example 25: tert-butyl (S)-4-(2-(5-fluorothiophene-2-carboxamido)-2-(6-methoxypyrid in-3- yl)ethyl)piperidine-1 -carbox late

The title compound (white solid) was prepared in 32% yield from tert-butyl (S)-4-(2-amino- 2-(6-methoxypyridin-3-yl)ethyl)piperidine-1-carboxylate and 5-fluorothiophene-2-carboxylic acid as described herein for the preparation of tert-butyl (S)-4-(2-(6-methoxypyridin-3-yl)- 2-(5-methylthiophene-2-carboxamido)ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C23H30FN3O4S: 463.2. Found: 462.2 (M-1) ^" . Ή NMR (400MHz, CDCI ₃ ) δ 8.17 (br s, 1 H), 7.56 (d, J = 7.8 Hz, 1 H), 7.11 (br s, 1 H), 6.75 (d, J = 8.6 Hz, 1 H), 6.47 (d, J = 3.5 Hz, 1 H), 5.96 (d, J = 7.4 Hz, 1 H), 5.19 (q, J = 7.3 Hz, 1 H), 4.26 - 3.99 (m, 2H), 3.93 (s, 3H), 2.77 - 2.50 (m, 2H), 1 .95 - 1 .66 (m, 4H), 1 .53 - 1.32 (m, 10H), 1.30 - 1 .04 (m, 2H).

Synthesis of amine intermediate tert-butyl 4-(2-amino-4-methylpentyl)piperidine-1 - carbo

The title compound was prepared in 3 steps from tert-butyl 4-(2-(methoxy(methyl)amino)- 2-oxoethyl)piperidine-1 -carboxylate and isobutylmagnesium bromide as described herein for the preparation of tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C16H32N2O2: 284.3. Found: 307.4 (M+23) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 4.27 - 3.87 (m, 2H), 2.98 - 2.85 (m, 1 H), 2.79 - 2.61 (m, 2H), 1 .80 - 1 .68 (m, 2H), 1 .66 - 1 .52 (m, 2H), 1 .46 (s, 9H), 1 .33 - 1 .19 (m, 4H), 1 .18 - 0.99 (m, 2H), 0.96 - 0.83 (m, 6H).

Example 26: tert-butyl 4-(4-methyl-2-(5-methylthiophene-2-carboxamido)pentyl)piperi dine- 1 -carboxylate

The title compound (white solid) was prepared from tert-butyl 4-(2-amino-4- methylpentyl)piperidine-1 -carboxylate and 5-methylthiophene-2-carboxylic acid as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate from tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1 - carboxylate. LCMS (ESI) m/z calcd for C22H36N2O3S: 408.2. Found: 407.5 (M-1 ) ^" . Ή NMR (400MHz, CDCI3) δ 7.30 (d, J = 3.5 Hz, 1 H), 6.74 (d, J = 3.1 Hz, 1 H), 5.43 (d, J = 9.4 Hz, 1H), 4.38-4.21 (m, 1H), 4.17-3.91 (m, 2H), 2.77-2.58 (m, 2H), 2.51 (s, 3H), 1.90 (d, J = 12.5 Hz, 1H), 1.72- 1.54 (m, 3H), 1.53- 1.23 (m, 13H), 1.21 - 1.00 (m, 2H), 1.00-0.84 (m, 6H). Example 27: tert-butyl 4-(2-4-bromobenzamido)-4-methylpentyl)piperidine-1-carboxyla te

The title compound (white solid) was prepared from tert-butyl 4-(2-amino-4- methylpentyl)piperidine-1-carboxylate and 4-bromobenzoic acid as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1-carboxylate from tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1- carboxylate. LCMS (ESI) m/z calcd for CzsHssBrNzOs: 466.2. Found: 467.3(M+1) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 7.67 - 7.54 (m, 4H), 5.69 (d, J = 9.4 Hz, 1 H), 4.44 - 4.26 (m, 1 H), 4.16-3.92 (m, 2H), 2.76-2.55 (m, 2H), 1.96- 1.85 (m, 1H), 1.75- 1.55 (m, 3H), 1.54- 1.30 (m, 13H), 1.23 - 1.02 (m, 2H), 1.00 - 0.88 (m, 6H).

Example 28: tert-butyl 4-(2-(5-bromothiophene-2-carboxamido)-4-methylpentyl)piperid ine- 1-carboxylate

The title compound (white solid) was prepared from tert-butyl 4-(2-amino-4- methylpentyl)piperidine-1-carboxylate and 5-bromothiophene-2-carboxylic acid as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1-carboxylate from tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1- carboxylate. LCMS (ESI) m/z calcd for CziHssBrNzOsS: 472.1. Found: 471.2 (M-1) ^" . ¹ H NMR (400MHz, methanol-c/ ₄ ) δ 7.48 (d, J = 3.9 Hz, 1 H), 7.14 (d, J = 3.9 Hz, 1H), 4.31 - 4.15 (m, 1H), 4.08 - 3.94 (m, 2H), 2.82 - 2.55 (m, 2H), 1.97- 1.84 (m, 1H), 1.67- 1.56 (m, 2H), 1.55- 1.23 (m, 14H), 1.19-0.95 (m, 2H), 0.95-0.83 (m, 6H).

Example 29: tert-butyl (S)-4-(2-(5-bromothiophene-2-carboxamido)-2-(6-methoxypyridi n-3- yl)ethyl)piperidine-1 -carbox late

The title compound (white solid) was prepared in 70% yield from tert-butyl (S)-4-(2-amino- 2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate and 5-bromothiophene-2- carboxylic acid as described herein for the preparation of tert-butyl (S)-4-(2-(4- bromobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for CahUoBrlSUC^S: 523.1. Found: 522.15 (M-1)-. Ή NMR (400MHz, methanol- c/4) δ 8.12 (d, J = 2.3 Hz, 1H), 7.70 (dd, J = 2.7, 8.6 Hz, 1H), 7.53 (d, J = 3.9 Hz, 1H), 7.15 (d, J = 3.9 Hz, 1H), 6.78 (d, J = 8.6 Hz, 1H), 5.19-5.09 (m, 1H), 4.09- 3.98 (m, 2H), 3.88 (s, 3H), 2.80 - 2.57 (m, 2H), 1.99 - 1.87 (m, 1 H), 1.83 - 1.66 (m, 3H), 1.57 - 1.46 (m, 1 H), 1.43 (s, 9H), 1.24- 1.06 (m, 2H).

Example 30: tert-butyl (S)-4-(2-(5-ethylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

The title compound (white solid) was prepared in 3 steps from tert-butyl (S,E)-4-(2-((tert- butylsulfinyl)imino)ethyl)piperidine-1 -carboxylate and phenylmagnesium bromide as described herein for the preparation of tert-butyl (R)-4-(2-(5-chlorothiophene-2- carboxamido)propyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C25H34N2O3S: 442.2. Found: 443.4 (M+1) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 7.42 - 7.23 (m, 6H), 6.76 (d, J = 3.5 Hz, 1 H), 5.99 (d, J = 8.2 Hz, 1 H), 5.27 (q, J = 7.8 Hz, 1 H), 4.18 - 3.93 (m, 2H), 2.85 (q, J = 7.7 Hz, 2H), 2.74 - 2.51 (m, 2H), 1 .94 - 1 .67 (m, 4H), 1 .45 (s, 10H), 1 .35 - 1 .05 (m, 5H). Example 31 : tert-butyl 4-(2-(5-bromothiophene-2-carboxamido)-2- cyclohexylethyl)piperidine-1 -carboxylate

The title compound (white solid) was prepared in 4 steps from tert-butyl 4-(2- (methoxy(methyl)amino)-2-oxoethyl)piperidine-1 -carboxylate and cyclohexylmagnesium chloride as described herein for the preparation of tert-butyl 4-(2-(5-ethylthiophene-2- carboxamido)-2-phenylethyl)piperidine-1 -carboxylate LCMS (ESI) m/z calcd for

C ₂ 3H35BrN20 ₃ S: 498.2. Found: 499.3 (M+1) ⁺ . ¹ H NMR (400MHz, methanol-c/ ₄ ) δ 8.07 (d, J = 9.4 Hz, 1 H), 7.51 (d, J = 3.9 Hz, 1 H), 7.14 (d, J = 4.3 Hz, 1 H), 4.09 - 3.88 (m, 3H), 2.81 - 2.52 (m, 2H), 1 .92 - 1 .70 (m, 5H), 1 .69 - 1 .36 (m, 15H), 1 .34 - 0.89 (m, 7H).

Example 32: isopropyl (S)-4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Preparation of tert-butyl (S)-4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

The title compound (white solid) was prepared in 3 steps from tert-butyl (S,E)-4-(2-((tert- butylsulfinyl)imino)ethyl)piperidine-1 -carboxylate and phenylmagnesium bromide as described herein for the preparation (S)-tert-butyl 4-(2-(5-chlorothiophene-2- carboxamido)-2-cyclopropylethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C25H31CIN2O3: 442.2. Found: 443.4 (M+1 ) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 7.69 (d, J = 7.8 Hz, 2H), 7.47 - 7.29 (m, 7H), 6.21 (d, J = 7.8 Hz, 1 H), 5.30 (q, J = 7.8 Hz, 1 H), 4.16 - 3.96 (m, 2H), 2.75 - 2.47 (m, 2H), 1 .98 - 1 .69 (m, 4H), 1 .50 - 1 .33 (m, 10H), 1 .24 - 1 .03 (m, 2H).

Preparation of isopropyl (S)-4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

The title compound was prepared in 54% yield from tert-butyl (S)-4-(2-(4- chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate and isopropyl chloroformate as described herein for the preparation of ethyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)- 2-cyclopropyl ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C24H29CIN2O3: 428.2. Found: 429.4 (M+1) ⁺ . ¹ H NMR (400MHz, methanol-c/ ₄ ) δ 7.80 (d, J = 8.6 Hz, 2H), 7.47 (d, J = 8.2 Hz, 2H), 7.41 - 7.35 (m, 2H), 7.32 (t, J = 7.6 Hz, 2H), 7.26 - 7.19 (m, 1 H), 5.23 (dd, J = 5.9, 9.8 Hz, 1 H), 4.86 - 4.77 (m, 1 H), 4.14 - 3.93 (m, 2H), 2.89 - 2.57 (m, 2H), 2.00 - 1 .65 (m, 4H), 1 .61 - 1 .46 (m, 1 H), 1 .30 - 1 .06 (m, 8H).

Example 33: isopropyl (S)-4-(2-(5-ethylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

The title compound (white solid) was prepared in 67% yield from tert-butyl (S)-4-(2-(5- ethylthiophene-2-carboxamido)-2-phenylethyl)piperidine-1 -carboxylate and isopropyl chloroformate as described herein for the preparation of ethyl (S)-4-(2-(5-chlorothiophene- 2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C24H32N2O3S: 428.2. Found: 429.3 (M+1) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 7.59 (d, J = 3.9 Hz, 1 H), 7.41 - 7.26 (m, 4H), 7.26 - 7.17 (m, 1 H), 6.83 (d, J = 3.5 Hz, 1 H), 5.18 (dd, J = 5.7, 10.0 Hz, 1 H), 4.86 - 4.75 (m, 1 H), 4.15 - 3.99 (m, 2H), 2.85 (q, J = 7.5 Hz, 2H), 2.79 - 2.58 (m, 2H), 2.00 - 1 .64 (m, 4H), 1 .63 - 1 .48 (m, 1 H), 1 .30 (t, J = 7.4 Hz, 3H), 1 .25 - 1 .04 (m, 8H).

Example 34: tert-butyl (R)-4-(2-(5-chlorothiophene-2-carboxamido)pent-4-en-1 - yl)piperidine-1 -carboxylate

The title compound (white solid) was prepared in 3 steps from tert-butyl (S,E)-4-(2-((tert- butylsulfinyl)imino)ethyl)piperidine-1-carboxylate and allylmagnesium bromide as described herein for the preparation of (S)-tert-butyl 4-(2-(5-chlorothiophene-2- carboxamido)-2-cyclopropylethyl)piperidine-1-carboxylate. LCMS (ESI) m/z calcd for C20H29CIN2O3S: 412.2. Found: 411.2 (M-1) ^" . ¹ H NMR (400MHz, methanol-c/ ₄ ) δ 7.52 (d, J 3.9 Hz, 1H), 7.01 (d, J = 3.9 Hz, 1H), 5.88 - 5.72 (m, 1H), 5.12 - 4.96 (m, 2H), 4.23 - 4.13 (m, 1 H), 4.06 - 3.95 (m, 2H), 2.84 - 2.53 (m, 2H), 2.37 - 2.17 (m, 2H), 1.90 - 1.78 (m, 1 H), 1.67- 1.57 (m, 1H), 1.57- 1.37 (m, 12H), 1.18-0.93 (m, 2H).

Example 35: phenyl 4-(2-(5-chlorothiophene-2-carboxamido)-4-methylpentyl)piperi dine-1- carboxylate

The title compound (white solid) was prepared in 77% yield from tert-butyl 4-(2-(5- chlorothiophene-2-carboxamido)-4-methylpentyl)piperidine-1 -carboxylate and phenyl chloroformate as described herein for the preparation of ethyl (S)-4-(2-(5-chlorothiophene- 2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C23H29CIN2O3S: 448.2. Found: 449.3 (M+1) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 7.43 - 7.31 (m, 2H), 7.25 (d, J = 3.9 Hz, 1H), 7.23-7.15 (m, 1H), 7.10 (d, J = 7.8 Hz, 2H), 6.92 (d, J = 3.9 Hz, 1H), 5.44 (d, J = 9.0 Hz, 1H), 4.41 -4.15 (m, 3H), 3.04-2.65 (m, 2H), 2.11 -1.90 (m, 1 H), 1.77 - 1.63 (m, 2H), 1.51 -1.13 (m, 7H), 1.02 - 0.88 (m, 6H). Example 36: phenyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2-(6-methoxypyrid in-3- yl)ethyl)piperidine-1 -carbox late

The title compound (off-white solid) was prepared in 74% yield from tert-butyl (S)-4-(2-(5- chlorothiophene-2-carboxamido)-2-(6-methoxypyridin-3-yl)ethy l)piperidine-1 -carboxylate and phenyl chloroformate as described herein for the preparation of ethyl (S)-4-(2-(5- chlorothiophene-2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C25H26CIN3O4S: 499.1 . Found: 498.3 (M-1) ^" . Ή NMR (400MHz, methanol-c/ ₄ ) δ 8.15 (d, J = 2.3 Hz, 1 H), 7.73 (dd, J = 2.3, 8.6 Hz, 1 H), 7.60 (d, J = 3.9 Hz, 1 H), 7.42 - 7.31 (m, 2H), 7.25 - 7.15 (m, 1 H), 7.11 - 7.00 (m, 3H), 6.80 (d, J = 8.6 Hz, 1 H), 5.25 - 5.11 (m, 1 H), 4.38 - 4.06 (m, 2H), 3.89 (s, 3H), 3.06 - 2.71 (m, 2H), 2.06 - 1 .71 (m, 4H), 1 .67 - 1 .53 (m, 1 H), 1 .45 - 1 .18 (m, 2H).

Example 37: phenyl (S)-4-(2-(4-chlorobenzamido)-2-(6-methoxypyridin-3- yl)ethyl)piperidine-1 -carbox late

The title compound (off-white solid) was prepared in 68% yield from tert-butyl (S)-4-(2-(4- chlorobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)piperidine-1 -carboxylate and phenyl chloroformate as described herein for the preparation of ethyl (S)-4-(2-(5-chlorothiophene- 2-carboxamido)-2-cyclopropyl ethyl)piperidine-1 -carboxylate. LCMS (ESI) m/z calcd for C27H28CIN3O4: 493.2. Found: 494.3 (M+1 ) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 8.18 (d, J = 2.3 Hz, 1 H), 7.82 (d, J = 8.6 Hz, 2H), 7.76 (dd, J = 2.3, 8.6 Hz, 1 H), 7.49 (d, J = 8.6 Hz, 2H), 7.41 - 7.32 (m, 2H), 7.26 - 7.17 (m, 1 H), 7.07 (d, J = 7.4 Hz, 2H), 6.81 (d, J = 8.6 Hz, 1 H), 5.32 - 5.20 (m, 1 H), 4.37 - 4.06 (m, 2H), 3.90 (s, 3H), 3.08 - 2.76 (m, 2H), 2.07 - 1 .74 (m, 4H), 1 .72 - 1 .54 (m, 1 H), 1 .45 - 1 .19 (m, 2H). Example 38: tert-butyl (R)-4-(2-(5-chlorothiophene-2-carboxamido)propyl)piperidine- 1 - carboxylate

Step 1 : Preparation of tert-butyl 4-((R)-2-(((S)-tert-butylsulfinyl)amino)propyl)piperidine -1 -carboxylate

A solution of tert-butyl (S,E)-4-(2-((tert-butylsulfinyl)imino)ethyl)piperidine-1 -carboxylate (250 mg, 0.756 mmol) in DCM (19 mL) was treated dropwise with 3M methylmagnesium chloride /THF (0.328 mL, 0.983 mmol), and stirred at RT for 6 hours. The reaction was quenched with saturated aqueous NH ₄ CI and extracted with DCM. The DCM solution was washed with water, brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by flash chromatography twice (silica gel, 0-10% MeOH/DCM; then 0-100%

acetone/hexanes, gradient elution) afforded the title compound (102 mg, 0.293 mmol, 39% yield) as white solid. LCMS (ESI) m/z calcd for C17H34N2O3S: 346.2. Found: 347.3 (M+1 ) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 4.23 - 3.90 (m, 2H), 3.54 - 3.36 (m, 1 H), 2.82 (d, J = 8.2 Hz, 1 H), 2.74 - 2.55 (m, 2H), 1 .73 - 1 .64 (m, 1 H), 1 .64 - 1 .54 (m, 3H), 1 .51 - 1 .41 (m, 10H), 1 .34 - 1 .19 (m, 12H), 1 .19 - 1 .00 (m, 2H). Step 2: Preparation of tert-butyl (R)-4-(2-aminopropyl)piperidine-1 -carboxylate hydrochloride

An ice cold solution of tert-butyl 4-((R)-2-(((S)-tert-butylsulfinyl)amino)propyl)piperidine-1 - carboxylate (100 mg, 0.289 mmol) in MeOH (1 .6 mL) was treated dropwise with 4M HCI/dioxane (0.072 mL, 0.289 mmol). The mixture was stirred in the ice bath for 5 hours, letting the bath to warm up to RT. The reaction was concentrated to dryness and the residue co-evaporated with MeCN, and dried under vacuum to give the title compound as a white solid in quantitative yield. LCMS (ESI) m/z calcd for C13H26N2O2: 242.2. Found 243.3 (M+1) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 4.15 - 3.96 (m, 2H), 3.42 - 3.33 (m, 1 H), 2.88 - 2.60 (m, 2H), 1 .79 - 1 .65 (m, 2H), 1 .64 - 1 .42 (m, 12H), 1 .29 (d, J = 6.6 Hz, 3H), 1 .16 - 1 .01 (m, 2H).

Step 3: Preparation of tert-butyl (R)-4-(2-(5-chlorothiophene-2- carboxamido)propyl)piperidi -1 -carboxylate

A solution of tert-butyl (R)-4-(2-aminopropyl)piperidine-1 -carboxylate hydrochloride (80 mg, 0.29 mmol) in DMF (2.9 mL) was treated with 5-chlorothiophene-2-carboxylic acid (51 .3 mg, 0.316 mmol), DIEA (0.200 mL, 1 .15 mmol), HATU (164 mg, 0.430 mmol), and stirred at RT for 18 hours. The reaction was quenched with 2M NH3/MeOH and stirred for an additional 2 hours. The mixture was diluted with water and extracted with EtOAc. The EtOAc solution was washed with 1 N HCI, saturated aqueous NaHC0 ₃ , brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by flash chromatography (0-80%

EtOAc/hexanes) afforded the title compound (90 mg, 77% yield) as white solid. LCMS (ESI) m/z calcd for C18H27CIN2O3S: 386.1 . Found: 385.4 (M-1) ^" . ¹ H NMR (400MHz, methanol-c/4) δ 7.52 (d, J = 3.9 Hz, 1 H), 7.00 (d, J = 4.3 Hz, 1 H), 4.27 - 4.13 (m, 1 H), 4.07 - 3.96 (m, 2H), 2.84 - 2.56 (m, 2H), 1 .86 - 1 .75 (m, 1 H), 1 .69 - 1 .31 (m, 13H), 1 .19 (d, J = 6.2 Hz, 3H), 1 .17 - 0.96 (m, 2H).

Example 39: (S)-5-chloro-N-(2-(1 -(3,3-dimethylbutanoyl)piperidin-4-yl)-1 -(6- methoxypyridin-3-yl)ethyl)thiophene-2-carboxamide

Step 1 : Preparation of (S)-5-chloro-N-(1 -(6-methoxypyridin-3-yl)-2-(piperidin-4- yl)ethyl)thiophene-2-carboxamide hydrochloride

A solution of tert-butyl (S)-4-(2-(5-chlorothiophene-2-carboxamido)-2-(6-methoxypyrid in-3- yl)ethyl)piperidine-1 -carboxylate (260 mg, 0.542 mmol) in 1 ,4-dioxane (3.60 mL) and MeOH (1 .8 mL) was treated with 4M HCI/dioxane (0.677 mL, 2.71 mmol) and stirred at RT for 18 hours. The mixture was concentrated to dryness at reduced pressure to afford the title compound as a white solid in quantitative yeild. LCMS (ESI) m/z calcd for

Ci ₈ H ₂₂ CIN ₃ 0 ₂ S: 379.1 . Found: 380.2 (M+1 ) ⁺ . Step 2: Preparation of (S)-5-chloro-N-(2-(1 -(3,3-dimethylbutanoyl)piperidin-4-yl)-1 -(6- methoxypyridin-3-yl)ethyl)thio hene-2-carboxamide

An ice cold solution of (S)-5-chloro-N-(1 -(6-methoxypyridin-3-yl)-2-(piperidin-4- yl)ethyl)thiophene-2-carboxamide hydrochloride (55 mg, 0.110 mmol) in DCM (1 .1 ml_) was treated with TEA (0.046 ml_, 0.33 mmol), followed by a solution of 3,3- dimethylbutanoyl chloride (0.018 ml_, 0.132 mmol) in DCM (0.5 mL) dropwise. The reaction was warmed to RT for 2.5 hours, diluted with water, and extracted with DCM. The DCM solution was washed with brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by reverse phase HPLC (C18, 30-100% MeCN/water with 0.1 % formic acid) afforded the title compound (34 mg, 62 % yield) as white solid. LCMS (ESI) m/z calcd for C24H32CIN3O3S: 477.2. Found: 478.3 (M+1 ) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 8.13 (s, 1 H), 7.71 (d, J = 8.6 Hz, 1 H), 7.63 - 7.55 (m, 1 H), 7.07 - 6.96 (m, 1 H), 6.79 (d, J = 8.6 Hz, 1 H), 5.22 - 5.11 (m, 1 H), 4.63 - 4.48 (m, 1 H), 4.12 - 3.98 (m, 1 H), 3.88 (s, 3H), 3.10 - 2.95 (m, 1 H), 2.54 (q, J = 12.8 Hz, 1 H), 2.42 - 2.18 (m, 2H), 2.04 - 1 .50 (m, 5H), 1 .33 - 1 .07 (m, 2H), 1 .02 (s, 9H). Example 40: (S)-N-(tert-butyl)-4-(2-(5-chlorothiophene-2-carboxamido)-2- (6- methoxypyridin-3-yl)ethyl)pi eridine-1 -carboxamide

A solution of (S)-5-chloro-N-(1 -(6-methoxypyridin-3-yl)-2-(piperidin-4-yl)ethyl)thiophene-2 - carboxamide hydrochloride (55 mg, 0.110 mmol) in DCM (1 .1 mL) was treated with TEA (0.061 mL, 0.44 mmol), followed by a solution of t-butyl isocyanate (0.025 mL, 0.22 mmol) in DCM (0.5 mL) dropwise. The reaction was stirred at RT for 3 hours, diluted with water and 1 N HCI and extracted with DCM. The DCM solution was washed with saturated aqueous NaHC0 ₃ , brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by reverse phase HPLC (C18, 30-100% MeCN/water with 0.1 % formic acid) afforded the title compound (28 mg, 50 % yield) as white solid. LCMS (ESI) m/z calcd for C23H31CIN4O3S: 478.2. Found: 479.4 (M+1) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 8.12 (d, J = 2.3 Hz, 1 H), 7.70 (dd, J = 2.7, 8.6 Hz, 1 H), 7.58 (d, J = 3.9 Hz, 1 H), 7.02 (d, J = 3.9 Hz, 1 H), 6.78 (d, J = 8.6 Hz, 1 H), 5.58 (s, 1 H), 5.19 - 5.10 (m, 1 H), 4.00 - 3.90 (m, 2H), 3.88 (s, 3H), 2.74 - 2.56 (m, 2H), 2.01 - 1 .86 (m, 1 H), 1 .83 - 1 .64 (m, 3H), 1 .57 - 1 .42 (m, 1 H), 1 .30 (s, 9H), 1 .26 - 1 .07 (m, 2H).

Example 41 : (S)-5-chloro-N-(2-(1 -(isobutylsulfonyl)piperidin-4-yl)-1 -(6-methoxypyridin-3- yl)ethyl)thiophene-2-carboxamide

An ice cold solution of (S)-5-chloro-N-(1 -(6-methoxypyridin-3-yl)-2-(piperidin-4- yl)ethyl)thiophene-2-carboxamide hydrochloride (55 mg, 0.110 mmol) in DCM (1 .1 was treated with TEA (0.046 mL, 0.33 mmol), followed by a solution of isobutanesulfonyl chloride (0.029 mL, 0.22 mmol) in DCM (0.5 mL) dropwise. The reaction was warmed to RT for 3.5 hours, treated with additional isobutanesulfonyl chloride (25 uL), stirred at 40 °C for 1 hour, and then cooled to RT overnight. The mixture was diluted with water and extracted with DCM The DCM solution was washed with brine, dried over Na2S04, filtered, and concentrated. Purification by reverse phase HPLC (C18, 30-100%

MeCN/water with 0.1 % formic acid) afforded the title compound (28 mg, 50% yield) as a white solid. LCMS (ESI) m/z calcd for C22H30CIN3O4S2: 499.1 . Found: 500.3 (M+1) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 8.17 (d, J = 1 .6 Hz, 1 H), 7.56 (dd, J = 2.0, 8.6 Hz, 1 H), 7.23 (d, J = 3.9 Hz, 1 H), 6.89 (d, J = 3.5 Hz, 1 H), 6.75 (d, J = 8.6 Hz, 1 H), 5.96 (d, J = 8.2 Hz, 1 H), 5.20 (q, J = 7.7 Hz, 1 H), 3.93 (s, 3H), 3.84 - 3.67 (m, 2H), 2.77 - 2.54 (m, 4H), 2.34 - 2.18 (m, 1 H), 2.00 - 1 .74 (m, 4H), 1 .49 - 1 .29 (m, 3H), 1 .09 (d, J = 6.6 Hz, 6H).

Example 42: phenyl (R)-4-(2-(5-chlorothiophene-2-carboxamido)propyl)piper

idine-1 -carboxylate

A solution of tert-butyl (R)-4-(2-(5-chlorothiophene-2-carboxamido)propyl)piperidine- 1 - carboxylate (56 mg, 0.145 mmol) in 1 ,4-dioxane (1 mL) and MeOH (0.5 mL) was treated with 4M HCI/dioxane (0.181 mL, 0.724 mmol), stirred at RT for 5 hours and then concentrated to dryness at reduced pressure. The residue was suspended in DCM (1 mL). The mixture was treated with TEA (0.061 mL, 0.43 mmol), followed by phenyl

chloroformate (0.027 mL, 0.22 mmol). After stirring at RT for 30 minutes, the mixture was diluted with water and extracted with DCM. The DCM solution was washed with brine, dried over Na2S04, filtered, and concentrated. Purification by reverse phase HPLC (C18, 30-100% MeCN/water with 0.1 % formic acid) afforded the title compound (44 mg, 72% yield) as white solid. LCMS (ESI) m/z calcd for C20H23CIN2O3S: 406.1 . Found: 407.3 (M+1 ) ⁺ . ¹ H NMR (400MHz, methanol-c/ ₄ ) δ 8.24 (d, J = 8.6 Hz, 1 H), 7.54 (d, J = 3.9 Hz, 1 H), 7.41 - 7.30 (m, 2H), 7.25 - 7.15 (m, 1 H), 7.06 (d, J = 7.8 Hz, 2H), 7.01 (d, J = 4.3 Hz, 1 H), 4.36 - 4.06 (m, 3H), 3.08 - 2.74 (m, 2H), 1 .98 - 1 .85 (m, 1 H), 1 .81 - 1 .69 (m, 1 H), 1 .67 - 1 .52 (m, 2H), 1 .49 - 1 .39 (m, 1 H), 1 .36 - 1 .06 (m, 5H).

Example 43: (S)-5-chloro-N-(2-(1 -(2,2-difluoro-2-phenylacetyl)piperidin-4-yl)-1 -(6- methoxypyridin-3-yl)ethyl)thio hene-2-carboxamide

A solution of (S)-5-chloro-N-(1 -(6-methoxypyridin-3-yl)-2-(piperidin-4-yl)ethyl)thiophene-2 - carboxamide hydrochloride (40 mg, 0.080 mmol) in DMF (0.8 mL) was treated with 2,2- difluoro-2-phenylacetic acid (15 mg, 0.088 mmol), DIEA (0.042 mL, 0.24 mmol), HATU (46 mg, 0.120 mmol), and stirred at RT for 3.5 hours. The reaction was quenched with 2M NH ₃ /MeOH and stirred for an additional 45 min. The mixture was diluted with water and extracted with EtOAc. The EtOAc solution was washed with 1 N HCI, saturated aqueous NaHC0 ₃ , brine, dried over Na ₂ S0 ₄ , filtered, and concentrated. Purification by reverse phase HPLC (C18, 30-100% MeCN/water with 0.1 % formic acid) afforded the title compound (24 mg, 55 % yield) as white solid. LCMS (ESI) m/z calcd for C26H26CIF2N3O3S: 533.1 . Found: 534.3 (M+1) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 8.14 (br s, 1 H), 7.64 - 7.38 (m, 6H), 7.22 (d, J = 3.5 Hz, 1 H), 6.88 (d, J = 3.9 Hz, 1 H), 6.75 (d, J = 8.6 Hz, 1 H), 5.96 (br s, 1 H), 5.26 - 5.04 (m, 1 H), 4.73 - 4.46 (m, 1 H), 4.06 - 3.79 (m, 4H), 2.91 - 2.50 (m, 2H), 1 .96 - 1 .67 (m, 4H), 1 .56 - 1 .38 (m, 1 H), 1 .34 - 1 .09 (m, 1 H), 1 .07 - 0.76 (m, 1 H). Example 44: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

Step 1 : Preparation of tert-butyl 4-(hydroxymethyl)piperidine-1 -carboxylate

To an ice cold solution of 1 -(tert-butoxycarbonyl)piperidine-4-carboxylic acid (5.00 g, 21 .8 mmol) in THF (50 mL) was slowly added 1 M BH ₃ -THF in THF (32.7 ml_, 32.7 mmol) and the mixture was allowed to stir at 0 °C for 2 hours after which time TLC (10% MeOH/DCM, KMn0 ₄ stain) indicated complete reaction. MeOH (5 mL) was added dropwise and the mixture was stirred at ambient temperature for 10 minutes. Saturated NaHC0 ₃ (50 mL) was added and the mixture was extracted with EtOAc. The extracts were washed with brine, dried over Na ₂ S0 ₄ , filtered and concentrated to afford the title compound as a viscous colorless oil (3.53 g, 75% yield). ¹ H NMR (400MHz, DMSO-c/ ₆ ) δ 4.45 (t, J = 5.3 Hz, 1 H), 4.00 - 3.85 (m, 2H), 3.23 (t, J = 5.8 Hz, 2H), 2.79 - 2.53 (m, 2H), 1 .66 - 2H), 1 .55 - 1 .44 (m, 1 H), 1 .43 - 1 .33 (m, 9H), 1 .01 -0.90 (m, 2H).

Step 2: Preparation of tert-butyl 4-(iodometh l)piperidine-1 -carboxylate

To a stirred solution of tert-butyl 4-(hydroxymethyl)piperidine-1 -carboxylate (3.53 g, 16.4 mmol), triphenylphosphine (6.86 g, 26.2 mmol) and imidazole (1 .78 g, 26.2 mmol) in DCM (100 mL) at 0 °C was added iodine (6.64 g, 26.2 mmol). The mixture was stirred at 0 °C for 5 minutes, then warmed to ambient temperature and stirred overnight (excluded from light by wrapping vessel in aluminum foil after removing from ice bath). The yellow-brown reaction mixture was diluted with hexanes (200 mL) and the triphenylphosphine-oxide precipitate was filtered off. Hexanes (200 mL) was added to the filtrate (some additional precipitate and a reddish-brown oily residue was observed) and the mixture was filtered once more to remove the solids. The filtrate was concentrated and the residue was purified by flash chromatography (silica gel, 0-40% EtOAc/hexanes, gradient elution) to afford the title compound as a colorless oil (3.96 g, 74% yield). ¹ H NMR (400MHz, CDCI ₃ ) δ 4.34 - 3.95 (m, 2H), 3.10 (d, J = 6.4 Hz, 2H), 2.69 (t, J = 12.0 Hz, 2H), 1 .83 (d, J = 13.2 Hz, 2H), 1 .69 - 1 .54 (m, 1 H), 1 .46 (s, 9H), 1 .14 (dq, J = 4.2, 12.3 Hz, 2H). Step 3: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-3-ethoxy-3- oxopropyl)piperidine-1 -carboxylate

To a solution of ethyl 2-((diphenylmethylene)amino)acetate (2.60 g, 9.73 mmol) in THF (60 mL) at -78 °C was added 1 M potassium bis(trimethylsilyl)amide/THF (12.16 mL, 12.16 mmol) and the resulting yellow solution was stirred at -78 °C for 30 minutes. A solution of tert-butyl 4-(iodomethyl)piperidine-1 -carboxylate (3.95 g, 12.16 mmol) in THF (15 mL) was slowly added. The reaction mixture was stirred at -78 °C for 30 minutes, 0 °C for one hour and then warmed to ambient temperature and stirred overnight. A solution of citric acid (2.34 g, 12.2 mmol) in water (100 mL) was added and the mixture was diluted with EtOAc. The mixture was partitioned and separated. The aqueous phase was further extracted with EtOAc and the combined organic phases were dried over MgS0 ₄ , filtered and concentrated. The residue was purified by flash chromatography (silica gel, 0-50% EtOAc/hexanes, gradient elution) to afford a pale yellow residue (3.6 g). The purified residue was dissolved in ethanol (80 mL), treated with 50 wt% aqueous hydroxylamine (2.50 mL, 40.8 mmol), stirred for 5 minutes and then treated with acetic acid (2.50 mL, 43.7 mmol). The reaction mixture was stirred overnight at ambient temperature. Brine (150 mL) was added and the mixture was made slightly basic by adding 1 .0 N NaOH. The mixture was extracted once with EtOAc and twice with DCM. The combined extracts were dried over Na ₂ S0 ₄ , filtered and concentrated to a pale yellow residue. To a solution of the crude residue, 5-chlorothiophene-2-carboxylic acid (1 .26 g, 7.75 mmol) and DIEA (2.03 mL, 1 1 .6 mmol) in DMF (25 mL) was added 50% T3P/EtOAc (7.38 mL, 12.4 mmol) and the mixture was stirred at ambient temperature for approximately two hours. The mixture was partitioned between EtOAc and saturated aqueous NaHC0 ₃ . The layers were separated and the aqueous phase was further extracted with EtOAc. The combined organic extracts were washed with water, then brine, dried over Na2S04, filtered and concentrated. The residue was purified by flash chromatography (silica gel, 0-40% EtOAc/hexanes, gradient elution) to afford the title compound a white foam (1 .60 g, 37% yield). LCMS (ESI) m/z calcd for C20H29CIN2O5S: 444.2. Found: 445.3 (M+1) ⁺ . Ή NMR (400MHz, CDC ) δ 7.32 (d, J = 3.8 Hz, 1 H), 6.92 (d, J = 3.8 Hz, 1 H), 6.43 (d, J = 8.2 Hz, 1 H), 4.80 (dt, J = 5.3, 8.4 Hz, 1 H), 4.23 (q, J = 7.1 Hz, 2H), 4.17 - 3.98 (m, 2H), 2.77 - 2.57 (m, 2H), 1 .90 - 1 .76 (m, 2H), 1 .73 - 1 .61 (m, 2H), 1 .60 - 1 .50 (m, 1 H), 1 .45 (s, 9H), 1 .31 (t, J = 7.1 Hz, 3H), 1 .23 - 1 .06 (m, 2H). Step 4: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-3-hydrazinyl-3- oxopropyl)piperidine-1 -carboxylate

A solution of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-3-ethoxy-3- oxopropyl)piperidine-1 -carboxylate (500 mg, 1 .12 mmol) in ethanol (8.0 mL) was treated with hydrazine (0.176 mL, 5.62 mmol) and then stirred overnight at ambient temperature. LCMS indicated ~50% conversion to the desired product. Additional hydrazine (0.176 mL, 5.62 mmol) was added and the mixture was stirred at ambient temperature for seven hours. LCMS indicated 90% completion. Additional hydrazine (0.176 mL, 5.62 mmol) was added and then stirred for three days. The mixture was concentrated and then placed under vacuum to afford the title compound as an off-white solid in quantitative yield.

LCMS (ESI) m/z calcd for C18H27CIN4O4S: 430.1 . Found: 431 .3 (M+1) ⁺ .

Step 5: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-oxo-4,5- dihydro-1 ,3,4-oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

A suspension of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-3-hydrazinyl-3- oxopropyl)piperidine-1 -carboxylate (521 mg, 1 .21 mmol) and DIEA (0.422 mL, 2.418 mmol) in DCM (5.0 mL) was treated with a solution of triphosgene (143 mg, 0.484 mmol) in DCM (1 .0 mL, sonicated until triphosgene dissolved) to give a yellow solution. An exotherm was observed and the mixture was stirred at ambient temperature for 30 minutes. The mixture was concentrated and then purified by flash chromatography (silica gel, 0-10% MeOH/DCM, gradient elution) to afford the title compound as a colorless residue (351 mg, 37% yield). LCMS (ESI) m/z calcd for C19H25CIN4O5S: 456.1 . Found: 457.2 (M+1) ⁺ .

Step 6: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5- (diethylamino)-l ,3,4-oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

To a solution of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-oxo-4,5-dihydro- 1 ,3,4-oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate (50 mg, 0.109 mmol) in DMF (1 .09 mL) was sequentially added DIEA (38.2 μΙ, 0.219 mmol) and diethylamine (22.9 μΙ, 0.219 mmol). After stirring for several minutes, BOP (53.2 mg, 0.120 mmol) was added and the mixture was stirred at ambient temperature overnight. The mixture was purified directly by reverse phase HPLC (C18, 10-100% MeCN/water with 0.1 % formic acid) to afford the title compound as a white solid (28 mg, 50% yield). LCMS (ESI) m/z calcd for C23H34CIN5O4S: 51 1 .2. Found: 512.4 (M+1) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 7.40 (d, J = 3.9 Hz, 1 H), 6.79 (d, J = 3.9 Hz, 1 H), 5.50 - 5.37 (m, 1 H), 4.21 - 3.90 (m, 2H), 3.42 (q, J = 7.0 Hz, 4H), 2.66 (m, 2H), 1 .90 - 1 .58 (m, 5H), 1 .43 (s, 9H), 1 .20 (t, J = 7.2 Hz, 8H).

Example 45: ethyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

A solution of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate (108 mg, 0.21 1 mmol) in methanol (1 .0 mL) was treated with 4M HCI/dioxane (2.0 mL, 8.00 mmol). The mixture was stirred at ambient temperature for 30 minutes and then concentrated to a pale yellow residue. The residue was suspended in TEA (0.1 18 ml_, 0.844 mmol) and DCM (2.0 ml_) and then treated with a solution of ethyl chloroformate (0.024 ml_, 0.253 mmol) in DCM (76 uL). The mixture was allowed to stir at ambient temperature for 45 minutes. The mixture was partitioned between DCM and saturated aqueous NaHC03 and the phases were separated. The aqueous phase was extracted with DCM and the combined organic phases were dried over MgS0 ₄ , filtered and concentrated. The residue was purified by flash chromatography (silica gel, 0-100% EtOAc/hexanes, gradient elution) to afford the title compound as a white solid (73 mg, 72% yield). LCMS (ESI) m/z calcd for

C21 H30CIN5O4S: 483.2. Found: 484.4 (M+1 ) ⁺ . Ή NMR (400MHz, CD ₃ OD) δ 8.92 (d, J = 8.6 Hz, 1 H), 7.59 (d, J = 3.9 Hz, 1 H), 7.04 (d, J = 4.3 Hz, 1 H), 5.38 - 5.32 (m, 1 H), 4.16 - 4.05 (m, 4H), 3.44 (q, J = 7.0 Hz, 4H), 2.89 - 2.65 (m, 2H), 1 .99 - 1 .93 (m, 2H), 1 .88 - 1 .71 (m, 2H), 1 .70 - 1 .57 (m, 1 H), 1 .28 - 1 .07 (m, 1 1 H). Example 46: tert-butyl 4-(3-methyl-2-(5-methylthiophene-2-carboxamido)butyl)piperid ine- 1 -carboxylate

Step 1 : Preparation of tert-butyl 4-(3-methyl-2-oxobutyl)piperidine-1 -carboxylate

To a solution of tert-butyl 4-(2-(methoxy(methyl)amino)-2-oxoethyl)piperidine-1 - carboxylate (1 .04 g, 3.61 mmol) in THF (20 mL) at 0 °C was added 2M iPrMgCI/THF by dropwise addition. After stirring at 0 °C for 5 minutes, the solution was allowed to warm to RT. After 80 minutes, the mixture was cooled to 0 °C, then treated slowly with additional 2M iPrMgCI/THF(4.52 mL, 9.04 mmol) and stirred for several minutes at ice bath temperature. The ice bath was removed and the mixture was allowed to stir at ambient temperature overnight. Saturated NH ₄ CI was added, the mixture was stirred for 10 minutes and then extracted with EtOAc. The extracts were washed with saturated NaHC0 ₃ , then brine, dried over Na ₂ S0 ₄ , filtered and concentrated. The residue was purified by flash chromatography (silica gel, 0-70% EtOAc/hexanes, gradient elution) to afford the title compound as a colorless residue (0.294 g, 30% yield). ¹ H NMR (400MHz, CDC ) 5 4.16 - 3.91 (m, 1 H), 2.82 - 2.62 (m, 2H), 2.60 - 2.49 (m, 1 H), 2.40 - 2.32 (m, 2H), 2.07 - 1 .93 (m, 1 H), 1 .67 - 1 .57 (m, 3H), 1 .47 - 1 .40 (m, 9H), 1 .16 - 0.98 (m, 8H). Step 2: Preparation of tert-butyl 4-(2-amino-3-methylbutyl)piperidine-1 -carboxylate

A solution of tert-butyl 4-(3-methyl-2-oxobutyl)piperidine-1 -carboxylate (294 mg, 1 .091 mmol), sodium acetate (448 mg, 5.46 mmol) and hydroxylamine hydrochloride (152 mg, 2.18 mmol) in ethanol (6.0 mL) and water (3.0 mL) was stirred at 90 °C for 150 minutes. The reaction was cooled to ambient temperature, water was added and then extracted with EtOAc. The extracts were washed with brine, dried over Na ₂ S0 ₄ , filtered and concentrated to give the crude oxime product as a viscous colorless oil. A solution of the crude oxime product in methanol (8 mL) was purged with nitrogen, treated with 10% Pd/C (40 mg, 0.376 mmol) and then stirred under hydrogen (60 psi) at 60 °C for three days. TLC indicated starting material still remained. The mixture was purged with nitrogen, additional 10% Pd/C (40 mg, 0.376 mmol) added and then stirred under hydrogen (60 psi) at 60 °C overnight. The mixture was cooled to ambient temperature, filtered through a PTFE filter and then concentrated. The residue was purified by flash chromatography (silica gel, 0-10% MeOH/DCM, MeOH containing 1 % NH ₄ OH, gradient elution) to afford the title compounds as a colorless residue (201 mg, 68%). ¹ H NMR (400MHz, CDCI ₃ ) δ 4.22 - 3.94 (m, 1 H), 2.78 - 2.56 (m, 3H), 1 .77 - 1 .68 (m, 1 H), 1 .64 - 1 .49 (m, 3H), 1 .44 (s, 9H), 1 .30 - 0.94 (m, 5H), 0.90 - 0.81 (m, 6H).

Step 3: Preparation of tert-butyl 4-(3-methyl-2-(5-methylthiophene-2- carboxamido)butyl)piperidin -1 -carboxylate

A solution of tert-butyl 4-(2-amino-3-methylbutyl)piperidine-1 -carboxylate (41 mg, 0.152 mmol), 5-methylthiophene-2-carboxylic acid (32.3 mg, 0.227 mmol) and DIEA (0.048 mL, 0.273 mmol) in DMF (1 .0 mL) was treated with 50% T3P/EtOAc (0.144 mL, 0.243 mmol) and the mixture was allowed to stir at ambient temperature for 140 minutes. Additional 5- chlorothiophene-2-carboxylic acid (8 mg), DIEA (14 uL) and 50% T3P (45 uL) were added and the mixture was stirred at ambient temperature for 30 minutes. The mixture was purified directly by reverse phase HPLC (C18, 10-100% MeCN/water with 0.1 % formic acid) to afford the title compound as a white solid (24 mg, 39% yield). LCMS (ESI) m/z calcd for C21 H34N2O3S: 394.2. Found: 395.4 (M+1) ⁺ . ¹ H NMR (400MHz, CDC ) δ 7.33 - 7.30 (m, 1 H), 6.77 - 6.74 (m, 1 H), 5.56 - 5.48 (m, 1 H), 4.15 - 3.90 (m, 3H), 2.71 - 2.55 (m, 2H), 2.51 (s, 3H), 1 .94 - 1 .73 (m, 2H), 1 .61 - 1 .52 (m, 1 H), 1 .51 - 1 .28 (m, 12H), 1 .21 - 0.96 (m, 2H), 0.96 - 0.90 (m, 6H). Example 47: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(pentan-3-yl)-1 ,2,4- oxadiazol-3-yl)ethyl)piperidine-1 -carboxylate

Step 1 : Preparation of 3-(1 -(tert-butoxycarbonyl)piperidin-4-yl)-2-(5-chlorothiophene-2 - carboxamido)propanoic aci

A solution of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-3-ethoxy-3- oxopropyl)piperidine-1 -carboxylate ( 0.577 g, 1 .30 mmol) in ethanol (3.24 ml) and THF (9.73 ml) was treated with 2M LiOH (3.24 ml, 6.48 mmol). The mixture was stirred at ambient temperature for one hour and then concentrated. Water was added and the mixture was treated with 1 N HCI (3.2 ml_) to give a white precipitate. The solids were collected on filter paper (Buchner funnel) under suction filtration and then dried under vacuum to give the desired product as a white solid (0.513 g, 95% yield). LCMS (ESI) m/z calcd for Ci ₈ H ₂₅ CIN ₂ 0 ₅ S: 416.1 . Found: 417.1 (M+1 ) ⁺ . Ή NMR (400MHz, DMSO-d ₆ ) δ 12.84 - 12.55 (m, 1 H), 8.74 (d, J = 8.2 Hz, 1 H), 7.76 (d, J = 4.3 Hz, 1 H), 7.19 (d, J = 3.9 Hz, 1 H), 4.43 - 4.29 (m, 1 H), 3.99 - 3.74 (m, 2H), 2.80 - 2.52 (m, 2H), 1 .77 - 1 .44 (m, 5H), 1 .36 (s, 9H), 1 .10 - 0.85 (m, 2H). Step 2: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyanoethyl)piperidine-1 -car

A solution of 3-(1 -(tert-butoxycarbonyl)piperidin-4-yl)-2-(5-chlorothiophene-2 - carboxamido)propanoic acid (513 mg, 1 .230 mmol) and TEA (0.515 mL, 3.69 mmol) in DCM (12 mL) at 0 °C was treated with ethyl chloroformate (0.177 mL, 1 .846 mmol) and the mixture was allowed to stir at 0 °C for 45 minutes. The reaction mixture was treated with ammonia gas for 5 minutes (LCMS indicated complete conversion to the primary amide product). The mixture was concentrated to an off-white solid. To a suspension of the crude primary amide product and TEA (0.257 mL, 1 .846 mmol) in THF (15 mL) at 0 °C was added TFAA (0.209 mL, 1 .477 mmol) and the mixture was allowed to stir at 0 °C for 30 minutes. Additional TFAA (100 uL) was added and the mixture was allowed to stir at ambient temperature for 30 minutes. The mixture was partitioned between EtOAc and saturated NaHC0 ₃ . The aqueous layer was further extracted with EtOAc. The combined extracts were washed with brine, dried over Na ₂ S0 ₄ , filtered and concentrated. The residue was purified by flash chromatography (silica gel, 0-50% EtOAc/hexanes, gradient elution) to afford the title compound as a viscous pale yellow oil (473 mg, 97% yield). LCMS (ESI) m/z calcd for C18H24CIN3O3S: 397.1 . Found: 398.2 (M+1) ⁺ . ¹ H NMR

(400MHz, methanol-c/4) δ 7.57 (d, J = 4.3 Hz, 1 H), 7.06 (d, J = 3.9 Hz, 1 H), 5.05 (t, J = 8.0 Hz, 1 H), 4.12 - 3.99 (m, 2H), 2.85 - 2.63 (m, 2H), 1 .88 (t, J = 7.4 Hz, 2H), 1 .80 - 1 .60 (m, 3H), 1 .43 (s, 9H), 1 .23 - 1 .07 (m, 2H). Step 3: Preparation of (Z)-tert-butyl 4-(3-amino-2-(5-chlorothiophene-2-carboxamido)-3- (hydroxyimino)propyl)piperidine-1 -carbox late

A mixture of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-cyanoethyl)piperidi ne-1 - carboxylate (191 mg, 0.480 mmol), hydroxylamine hydrochloride (43.4 mg, 0.624 mmol) and sodium bicarbonate (121 mg, 1 .44 mmol) in ethanol (4.0 mL) was heated to 90 °C for 3 hours and then stirred at ambient temperature overnight. Water was added and the mixture was extracted with EtOAc. The extracts were washed with brine, dried over Na ₂ S0 ₄ , filtered and concentrated to afford the crude product as a white foam (199 mg, 96% yield). LCMS (ESI) m/z calcd for C18H27CIN4O4S: 430.1 . Found: 431 .3 (M+1) ⁺ .

Step 4: Preparation of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(pentan-3- yl)-1 , 2, 4-oxadiazol-3-yl)ethy

A solution of tert-butyl (Z)-4-(3-amino-2-(5-chlorothiophene-2-carboxamido)-3-

(hydroxyimino)propyl)piperidine-1 -carboxylate (53 mg, 0.123 mmol) and TEA (0.026 mL, 0.184 mmol) in DCM (1 .2 mL) at 0 °C was treated with a solution of 2-ethylbutanoyl chloride (0.020 mL, 0.15 mmol) in DCM (90 uL). The mixture was allowed to stir at ambient temperature for 10 minutes and then concentrated. The residue was suspended in acetonitrile (1 .2 mL), treated with DBU (0.022 mL, 0.148 mmol) and the mixture was transferred to a microwave vial. The mixture was subjected to microwave heating at 120 °C for 60 minutes. LCMS indicated approximately 65% conversion to the desired product. The reaction mixture was irradiated in the microwave at 120 °C for an additional 60 minutes. The mixture was concentrated and then purified by flash chromatography (silica gel, 0-50% EtOAc/hexanes, gradient elution) to afford the title compound as a colorless residue (32 mg, 50%). LCMS (ESI) m/z calcd for C24H35CIN4O4S: 510.2. Found: 51 1 .3 (M+1) ⁺ . Ή NMR (400MHz, CD ₃ OD) δ 7.62 (d, J = 4.3 Hz, 1 H), 7.03 (d, J = 4.3 Hz, 1 H), 5.40 - 5.34 (m, 1 H), 4.10 - 4.01 (m, 2H), 2.95 - 2.86 (m, 1 H), 2.82 - 2.59 (m, 2H), 2.01 - 1 .86 (m, 2H), 1 .86 - 1 .68 (m, 6H), 1 .65 - 1 .53 (m, 1 H), 1 .43 (s, 9H), 0.89 - 0.81 (m, 6H).

Example 48: tert-butyl 4-(2-(5-(diethylamino)-1 ,3,4-oxadiazol-2-yl)-2-(5-methylthiophene- 2-carboxamido)ethyl)piperidine-1 -carboxylate

The title compound was prepared according to the method described herein for the synthesis of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate employing 5-methylthiophene-2-carboxylic acid in step 3. The product was isolated as a pale yellow solid after flash chromatography (silica gel, 0-100% EtOAc/hexanes, gradient elution). LCMS (ESI) m/z calcd for

C24H37N5O4S: 491 .3. Found: 492.5 (M+1) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 7.56 (d, J = 3.5 Hz, 1 H), 6.83 - 6.80 (m, 1 H), 5.40 - 5.32 (m, 1 H), 4.05 (d, J = 12.9 Hz, 2H), 3.43 (q, J = 7.0 Hz, 4H), 2.81 - 2.61 (m, 2H), 2.51 (s, 3H), 2.01 - 1 .90 (m, 2H), 1 .84 - 1 .81 (m, 1 H), 1 .75 - 1 .69 (m, 1 H), 1 .68 - 1 .56 (m, 1 H), 1 .43 (s, 9H), 1 .27 - 1 .05 (m, 8H).

Example 49: tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-3-methylbutyl)piperidi ne-1 - carboxylate

The title compound was prepared according to the method described herein for the synthesis of tert-butyl 4-(3-methyl-2-(5-methylthiophene-2-carboxamido)butyl)piperid ine-1 - carboxylate, employing 5-ethylthiophene-2-carboxylic acid in step 3. The product was isolated as a white solid after reverse phase HPLC (C18, 10-100% MeCN/water with 0.1 % formic acid) purification. LCMS (ESI) m/z calcd for C22H36N2O3S: 408.2. Found: 409.4 (M+1) ⁺ . ¹ H NMR (400MHz, CDCI ₃ ) δ 7.33 (d, J = 3.5 Hz, 1 H), 6.77 (d, J = 3.9 Hz, 1 H), 5.53 (d, J = 9.8 Hz, 1 H), 4.17 - 3.87 (m, 3H), 2.86 (q, J = 7.5 Hz, 2H), 2.71 - 2.56 (m, 2H), 1 .93 - 1 .85 (m, 1 H), 1 .83 - 1 .73 (m, 1 H), 1 .62 - 1 .52 (m, 1 H), 1 .51 - 1 .27 (m, 15H), 1 .21 - 0.87 (m, 8H).

Example 50: tert-butyl 4-(2-(5-(cyclopropyl(ethyl)amino)-1 ,3,4-oxadiazol-2-yl)-2-(5- methylthiophene-2-carboxamido ethyl)piperidine-1 -carboxylate

The title compound was prepared according to the method described herein for the synthesis of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate, employing 5-methylthiophene-2-carboxylic acid in step 3 and N-ethylcyclopropanamine in step 6. The product was isolated as a colorless residue after reverse phase HPLC (C18, 10-100% MeCN/water with 0.1 % formic acid) purification. LCMS (ESI) m/z calcd for C25H37N5O4S: 503.3. Found: 504.4 (M+1 ) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 7.56 (d, J = 3.9 Hz, 1 H), 6.85 - 6.78 (m, 1 H), 5.39 - 5.33 (m, 1 H), 4.10 - 4.01 (m, 2H), 3.46 (q, J = 7.2 Hz, 2H), 2.85 - 2.60 (m, 3H), 2.50 (s, 3H), 2.04 - 1 .89 (m, 2H), 1 .86 - 1 .78 (m, 1 H), 1 .77 - 1 .70 (m, 1 H), 1 .68 - 1 .57 (m, 1 H), 1 .43 (s, 9H), 1 .26 - 1 .05 (m, 5H), 0.87 - 0.78 (m, 2H), 0.74 - 0.65 (m, 2H). Example 51 : phenyl 4-(2-(5-methylthiophene-2-carboxamido)-2-phenylethyl)piperid ine-1 - carboxylate

Step 1 : Preparation of tert-butyl 4-(2-(5-methylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

A solution of tert-butyl 4-(2-amino-2-phenylethyl)piperidine-1 -carboxylate (798 mg, 2.62 mmol), 5-methylthiophene-2-carboxylic acid (373 mg, 2.62 mmol) and DIEA (0.687 mL, 3.93 mmol) in DMF (15 mL) was treated with 50% T3P/EtOAc (2.497 mL, 4.19 mmol) and the mixture was stirred at ambient temperature overnight. Saturated NaHC0 ₃ was added and the mixture was extracted with EtOAc. The extracts were washed with water, then brine, dried over Na ₂ S0 ₄ , filtered and concentrated. The residue was purified by flash chromatography (silica gel, 0-50% EtOAc/hexanes, gradient elution) to afford the title compound a white foam (350 mg, 31 % yield). LCMS (ESI) m/z calcd for C24H32N2O3S: 428.2. Found: 429.4 (M+1) ⁺ . ¹ H NMR (400MHz, methanol-c/ ₄ ) δ 8.57 (d, J = 8.6 Hz, 1 H), 7.56 (d, J = 3.5 Hz, 1 H), 7.39 - 7.27 (m, 4H), 7.25 - 7.18 (m, 1 H), 6.80 (d, J = 3.1 Hz, 1 H), 5.22 - 5.13 (m, 1 H), 4.04 (d, J = 13.3 Hz, 2H), 2.78 - 2.59 (m, 2H), 2.49 (s, 3H), 1 .96 - 1 .86 (m, 1 H), 1 .85 - 1 .78 (m, 1 H), 1 .77 - 1 .65 (m, 2H), 1 .59 - 1 .48 (m, 1 H), 1 .43 (s, 9H), 1 .22 - 1 .05 (m, 2H).

Step 2: Preparation of phenyl 4-(2-(5-methylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carbox late

A solution of tert-butyl 4-(2-(5-methylthiophene-2-carboxamido)-2-phenylethyl)piperid ine- 1 -carboxylate (70 mg, 0.163 mmol) in methanol (0.75 mL) was treated with 4M

HCI/dioxane (1 .50 mL, 6.00 mmol). The mixture was stirred for 20 minutes at ambient temperature and then concentrated to give the intermediate amine hydrochloride as a pale yellow residue (78 mg). To a suspension of the intermediate and TEA (0.091 mL, 0.653 mmol) in DCM (3.0 mL) at 0 °C was added a solution of phenyl chloroformate (0.025 mL, 0.20 mmol) in DCM (450 uL) and the mixture stirred at ambient temperature for 20 minutes. Saturated NaHC0 ₃ was added and the mixture was extracted with DCM. The combined organic phases were dried over MgS0 ₄ , filtered and concentrated. The residue was purified by flash chromatography (silica gel, 0-50% EtOAc/hexanes, gradient elution) to afford the title compound as a white solid (54 mg, 73%). LCMS (ESI) m/z calcd for

C26H28N2O3S: 448.2. Found: 449.3 (M+1) ⁺ . Ή NMR (400MHz, methanol-c/ ₄ ) δ 8.60 (d, J = 8.6 Hz, 1 H), 7.58 (d, J = 3.9 Hz, 1 H), 7.42 - 7.29 (m, 6H), 7.26 - 7.17 (m, 2H), 7.08 - 7.04 (m, 2H), 6.82 - 6.79 (m, 1 H), 5.27 - 5.16 (m, 1 H), 4.35 - 4.22 (m, 1 H), 4.19 - 4.08 (m, 1 H), 3.06 - 2.74 (m, 2H), 2.49 (s, 3H), 2.02 - 1 .55 (m, 5H), 1 .41 - 1 .18 (m, 2H). Example 52: tert-butyl 4-(2-(5-(ethyl(methyl)amino)-1 ,3,4-oxadiazol-2-yl)-2-(5- methylthiophene-2-carboxamido)ethyl)piperidine-1 -carboxylate

The title compound was prepared according to the method described herein for the synthesis of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate, employing 5-methylthiophene-2-carboxylic acid in step 3 and N-methylethanamine in step 6. The product was isolated as a colorless residue after flash chromatography (silica gel, 0-100% EtOAc/hexanes, gradient elution). LCMS (ESI) m/z calcd for C23H35N5O4S: 477.2. Found: 478.4 (M+1 ) ⁺ . Ή NMR (400MHz, methanol-c/4) δ 7.56 (d, J = 3.9 Hz, 1 H), 6.85 - 6.79 (m, 1 H), 5.39 - 5.33 (m, 1 H), 4.10 - 4.00 (m, 2H), 3.43 (q, J = 7.0 Hz, 2H), 3.05 - 3.01 (m, 3H), 2.82 - 2.59 (m, 2H), 2.51 (s, 3H), 2.02 - 1 .89 (m, 2H), 1 .86 - 1 .78 (m, 1 H), 1 .76 - 1 .69 (m, 1 H), 1 .68 - 1 .55 (m, 1 H), 1 .49 - 1 .37 (m, 9H), 1 .26 - 1 .05 (m, 5H). Example 53: phenyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

A solution of tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(diethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate (60 mg, 0.1 17 mmol) in methanol (0.5 ml_) was treated with 4N HCI/dioxane (1 .00 ml_, 4.00 mmol) at ambient temperature. The mixture was stirred at ambient temperature for 10 minutes and then concentrated to afford the amine hydrochloride intermediate as a pale yellow residue. An ice cold suspension of the intermediate and TEA (0.065 ml_, 0.469 mmol) in DCM (2.0 mL) was treated with a solution of phenyl chloroformate (0.018 ml_, 0.141 mmol) in DCM (0.31 ml_). The cooling bath was removed and the mixture was stirred at ambient temperature for 45 minutes. The mixture was partitioned between DCM and saturated NaHC0 ₃ and the phases were separated. The aqueous phase was extracted with DCM and the combined organic phases were dried over MgS04, filtered and concentrated. The residue was purified by reverse phase HPLC (C18, 10-100% MeCN/water with 0.1 % formic acid) followed by flash chromatography (silica gel, 30-100% EtOAc/hexanes, gradient elution) to afford the title compound as a colorless residue (12 mg, 18% yield). LCMS (ESI) m/z calcd for C25H30CIN5O4S: 531 .2. Found: 532.4 (M+1 ) ⁺ . Ή NMR (400MHz, CDCI ₃ ) δ 7.78 - 7.47 (m, 1 H), 7.42 - 7.30 (m, 3H), 7.22 - 7.14 (m, 1 H), 7.11 - 7.06 (m, 2H), 6.84 (d, J = 3.9 Hz, 1 H), 5.51 - 5.43 (m, 1 H), 4.34 - 4.18 (m, 2H), 3.43 (q, J = 7.0 Hz, 4H), 3.08 - 2.63 (m, 2H), 2.00 - 1 .84 (m, 3H), 1 .81 - 1 .69 (m, 2H), 1 .31 - 1 .16 (m, 8H).

Examples 54 - 245 were prepared using methods similar to those described herein for examples 1 -53.

Example 54: tert-butyl 4-(2-(4-fluorobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)pipe ridine- 1 -carboxylate

Example 55: isopropyl 4-(2-(4-fluorobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)pipe ridine- 1-carboxylate

Example 56: isobutyl 4-(2-(4-fluorobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)pipe ridine- 1-carboxylate

Example 57: tert-butyl 4-(2- 4-bromobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 58: tert-butyl 4-(2-(5-fluorothiophene-2-carboxamido)-2-phenylethyl)piperid ine-1 - carboxylate

Example 59: tert-butyl 4-(2-cyclopentyl-2-(5-methylthiophene-2- carboxamido)ethyl)piperidin -1-carboxylate

Example 60: tert-butyl 4-(2-(5-ethylthiophene-2-carboxamido)-4-methylpentyl)piperid ine-1 - carboxylate

Example 61 : cyclobutyl 4-(2- 4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 62: prop-2-yn-1 -yl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 63: (S)-tert-butyl 4-(2-(4-bromobenzamido)-2-cyclopropylethyl)piperidine-1- carboxylate

Example 64: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclohexylethyl)piperidine-1 -carboxylate

Example 65: (S)-tert-butyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1- carboxylate

Example 66: (S)-ethyl 4-(2-(5-ethylthiophene-2-carboxamido)-2-phenylethyl)piperidi ne-1 - carboxylate

Example 67: phenyl 4-(2-(4-chlorobenzamido -4-methylpentyl)piperidine-1-carboxylate

Example 68: tert-butyl 4-(2- 4-chlorobenzamido)-2-phenylethyl)piperidine-1-carboxylate

Example 69: tert-butyl 4-(2-(5-methylthiophene-2-carboxamido)-2-phenylethyl)piperid ine- 1-carboxylate

Example 70: (R)-tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(6-methoxypyridin-3 - yl)ethyl)piperidine-1 -carboxylate

Example 71 : tert-butyl 4-(2-(4-bromo-3-fluorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 72: tert-butyl 4-(2-(4-iodobenzamido -2-phenylethyl)piperidine-1 -carboxylate

Example 73: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(dimethylamino)- 1 ,3,4-oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

Example 74: tert-butyl 4-(2-(4-bromobenzamido)-3-methylbutyl)piperidine-1 -carboxylate

Example 75: tert-butyl 4-(2- 4-chlorobenzamido)-4-methylpentyl)piperidine-1 -carboxylate

Example 76: tert-butyl 4-(2-(4-fluorobenzamido -4-methylpentyl)piperidine-1 -carboxylate

Example 77: cyclopropyl 4- 2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1-carboxylate

Example 78: tert-butyl 4-(2-cyclopentyl-2-(5-ethylthiophene-2- carboxamido)ethyl)piperidine-1-carboxylate

Example 79: tert-butyl 4-(2-(5-fluorothiophene-2-carboxamido)-4-methylpentyl)piperi dine- 1 -carboxylate

Example 80: tert-butyl 4-(2-cyclohexyl-2-(5-methylthiophene-2- carboxamido)ethyl)piperidine-1-carboxylate

Example 81 : (S)-ethyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 82: tert-butyl 4-(2-(5-(ethyl(2-methoxyethyl)amino)-1 ,3,4-oxadiazol-2-yl)-2-(5- methylthiophene-2-carboxamido)ethyl)piperidine-1 -carboxylate

Example 83: (S)-tert-butyl 4-(4-(benzylamino)-2-(5-chlorothiophene-2- carboxamido)butyl)piperidine-1-carboxylate

Example 84: tert-butyl 4-(2-(4-chloro-3-fluorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 85: ethyl 4-(2-(4-fluorobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)pipe ridine-1 - carboxylate

Example 86: tert-butyl 4-(2-phenyl-2-(4-(prop-2-yn-1 -yloxy)benzamido)ethyl)piperidine-1 - carboxylate

Example 87: tert-butyl 4-(2-phenyl-2-(5-propylthiophene-2-carboxamido)ethyl)piperid ine-1 - carboxylate

Example 88: tert-butyl 4-(2-(4-chlorobenzamido)-3-methylbutyl)piperidine-1 -carboxylate

Example 89: propyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 90: (S)-tert-butyl 4-(2-(4-chlorobenzamido)-2-cyclopropylethyl)piperidine-1- carboxylate

Example 91 : tert-butyl 4-(2-(4-bromobenzamido)-2-cyclohexylethyl)piperidine-1- carboxylate

Example 92: tert-butyl 4-(2-cyclohexyl-2-(5-fluorothiophene-2- carboxamido)ethyl)piperidine-1-carboxylate

Example 93: N-(2-(1-(2,2-difluoro-2-phenylacetyl)piperidin-4-yl)-1-pheny lethyl)-5- methylthiophene-2-carboxamide

Example 94: 5-methyl-N-(1-phenyl-2-(1-(2,2,2-trifluoroacetyl)piperidin-4 - yl)ethyl)thiophene-2-carboxamide

Example 95: N-(2-(1-(2,2-difluorobutanoyl)piperidin-4-yl)-1-phenylethyl) -5- methylthiophene-2-carboxamide

Example 96: tert-butyl 4-(2-(5-(butyl(ethyl)amino)-1 ,3,4-oxadiazol-2-yl)-2-(5- methylthiophene-2-carboxamido)ethyl)piperidine-1-carboxylate

Example 97: tert-butyl 4-(2-(4-cyclopropylbenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 98: tert-butyl 4-(2-(5-cyclopropylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

Example 99: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-3-methylbutyl)piperid ine-1 - carboxylate

Example 100: cyclopentyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

0ι Example 101 : tert-butyl 4-(2-(3-fluoro-4-iodobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 102: ethyl 4-(2-(4-chlorobenzamido -2-phenylethyl)piperidine-1 -carboxylate

Example 103: isopropyl 4-(2- 4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 104: phenyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate Example 105: cyclopropylmethyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 106: tert-butyl 4-(2-cyclohexyl-2-(5-ethylthiophene-2- carboxamido)ethyl)piperidine-1-carboxylate

Example 107: tert-butyl 4-(2- 4-fluorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 108: ethyl 4-(2-cyclopropyl-2-(4-fluorobenzamido)ethyl)piperidine-1 -carboxylate

Example 109: tert-butyl 4-(2-(3-fluoro-4-methoxybenzamido)-2-phenylethyl)piperidine- 1 - carboxylate

Example 110: tert-butyl 4-(2-phenyl-2-(4-(trifluoromethyl)benzamido)ethyl)piperidine -1 - carboxylate

Example 111 : tert-butyl 4-(2-(6-methoxypyridin-3-yl)-2-(4- (methylthio)benzamido)ethyl)piperidine-1 -carboxylate

Example 112: tert-butyl 4-(2-(5-(diethylamino)-1 ,3,4-oxadiazol-2-yl)-2-(4- fluorobenzamido)ethyl)piperidine-1 -carboxylate

Example 113: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-((2- methoxyethyl)(methyl)amino)-1 ,3,4-oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

Example 114: tert-butyl 4-(2-(3-fluoro-4-(prop-2-yn-1 -yloxy)benzamido)-2- phenylethyl)piperidine-1 -carboxylate

Example 115: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopentylethyl)piperidine- -carboxylate

Example 116: tert-butyl 4-(2-cyclopentyl-2-(5-fluorothiophene-2- carboxamido)ethyl)piperidine-1-carboxylate

Example 117: benzyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 118: tert-butyl 4-(2-(4-ethylbenzamido)-2-phenylethyl)piperidine-1-carboxyla te

Example 119: tert-butyl 4-(2-phenyl-2-(4-vinylbenzamido)ethyl)piperidine-1-carboxyla te

Example 120: ethyl 4-(2-(4-fluorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate Example 121 : phenyl 4-(2- 4-fluorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 122: tert-butyl 4-(2-(6-(diethylamino)pyridin-3-yl)-2-(4- fluorobenzamido)ethyl)piperidine-1 -carbox late

Example 123: (S)-tert- butyl 4-(2-(6-methoxynicotinamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 124: tert-butyl 4-(2-(5-isopropylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

Example 125: isobutyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1-carboxyl ate

Example 126: tert-butyl 4-(2-(4-bromobenzamido)-2-cyclopentylethyl)piperidine-1- carboxylate

Example 127: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(ethylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1-carboxylate

Example 128: tert-butyl 4-(2-(5-chlorothiophene-3-carboxamido)-2-phenylethyl)piperid ine- 1-carboxylate

Example 129: (S)-tert- butyl 4-(2-(5-chlorothiophene-2-carboxamido)-4- morpholinobutyl)piperidine-1 -carboxylate

Example 130: tert-butyl 4-(2-(4-methylbenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 131 : tert-butyl 4-(2-phenyl-2-(thiophene-2-carboxamido)ethyl)piperidine-1 - carboxylate

Example 132: tert-butyl 4-(2-(6-(cyclohexyloxy)pyridin-3-yl)-2-(4- fluorobenzamido)ethyl)piperidine-1 -carboxylate

Example 133: tert-butyl 4-(2-(4-cyclopropyl-3-fluorobenzamido)-2-phenylethyl)piperid ine- 1 -carboxylate

Example 134: methyl 4-(2-(4-chlorobenzamido -2-phenylethyl)piperidine-1 -carboxylate

Example 135: tert-butyl 4-(2-(4-chlorobenzamido)-2-cyclohexylethyl)piperidine-1 - carboxylate

Example 136: N-(2-(1 -(2,2-difluoro-2-(pyridin-2-yl)acetyl)piperidin-4-yl)-1 -phenylethyl)-5- methylthiophene-2-carboxamide

Example 137: 5-methyl-N-(1 -phenyl-2-(1 -phenylpiperidin-4-yl)ethyl)thiophene-2- carboxamide

Example 138: tert-butyl 4-(2-benzamido-2-phenylethyl)piperidine-1 -carboxylate

Example 139: tert-butyl 4-(2-(3-fluoro-4-methylbenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 140: tert-butyl 4-(2-(5-(benzyl(methyl)amino)-1 ,3,4-oxadiazol-2-yl)-2-(5- chlorothiophene-2-carboxamido)ethyl)piperidine-1 -carboxylate

Example 141 : tert-butyl 4-(2- 4-cyanobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 142: tert-butyl 4-(3-(benzylamino)-2-(4-fluorobenzamido)propyl)piperidine-1 - carboxylate

Example 143: tert-butyl 4-(2-(4-methoxybenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 144: tert-butyl 4-(2-(4-fluorobenzamido)-2-(6-isopropoxypyridin-3- yl)ethyl)piperidine-1 -carboxylate

Example 145: methyl 4-(2-(4-fluorobenzamido)-2-(6-methoxypyridin-3-yl)ethyl)pipe ridine- 1-carboxylate

Example 146: tert-butyl 4-(2-(3-fluorobenzamido)-2-phenylethyl)piperidine-1-carboxyl ate

Example 147: tert-butyl 4-(2-(3,4-difluorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 148: (S)-tert- butyl 4-(2-((6-chlorobenzo[d]oxazol-2-yl)amino)-2- cyclopropylethyl)piperidine-1 -carboxylate

Example 149: tert-butyl 4-(2-(4-(but-2-yn-1 -yloxy)benzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 150: cyclohexyl 4- 2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 151 : tert-butyl 4-(2-(4-chlorobenzamido)-2-cyclopentylethyl)piperidine-1 - carboxylate

Example 152: tert-butyl 4-(2-cyclohexyl-2-(4-fluorobenzamido)ethyl)piperidine-1 - carboxylate

Example 153: tert-butyl 4-(2-(5-methylthiophene-3-carboxamido)-2-phenylethyl)piperid ine- 1 -carboxylate

Example 154: N-(2-(1 -butyrylpiperidin-4-yl)-1 -phenylethyl)-4-chlorobenzamide

Example 155: (S)-tert- butyl 4-(2-(5-chlorothiophene-2-carboxamido)pent-4-en-1 - yl)piperidine-1 -carboxylate

Example 156: N-(2-(1 -benzoylpiperidin-4-yl)-1 -phenylethyl)-5-methylthiophene-2- carboxamide

Example 157: tert-butyl 4-(2-(6-methoxynicotinamido)-2-phenylethyl)piperidine-1- carboxylate

Example 158: ethyl 4-(2-cyclopropyl-2-(6-methoxynicotinamido)ethyl)piperidine-1 - carboxylate

Example 159: tert-butyl 4-(2-phenyl-2-(thiophene-3-carboxamido)ethyl)piperidine-1- carboxylate

Example 160: tert-butyl 4-(2-(6-(benzyloxy)pyridin-3-yl)-2-(4- fluorobenzamido)ethyl)piperidine-1 -carbox late

Example 161 : tert-butyl 4-(2-(4-chloro-3-methoxybenzamido)-2-phenylethyl)piperidine- 1 - carboxylate

Example 162: tert-butyl 4-(2-(4-cyano-3-fluorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 163: 4-chloro-N-(2-(1 -(3-methylbutanoyl)piperidin-4-yl)-1 -phenylethyl)benzamide

Example 164: 4-chloro-N-(2-(1 -(3,3-dimethylbutanoyl)piperidin-4-yl)-1 - phenylethyl)benzamide

Example 165: N-(tert-butyl)-4-(2-(4-chlorobenzamido)-2-phenylethyl)piperi dine-1 - carboxamide

Example 166: 4-chloro-N-(2-(1 -(isobutylsulfonyl)piperidin-4-yl)-1 -phenylethyl)benzamide

Example 167: tert-butyl 4-(2-(4-(but-2-yn-1-yloxy)-3-fluorobenzamido)-2- phenylethyl)piperidine-1-carboxylate

Example 168: tert-butyl 4-(2-(4-chlorothiophene-2-carboxamido)-2-phenylethyl)piperid ine- 1-carboxylate

Example 169: tert-butyl 4-(2-(4-fluorobenzamido)-2-(5-(pentan-3-yl)-1 ,2,4-oxadiazol-3- yl)ethyl)piperidine-1 -carboxylate

Example 170: (S)-tert- butyl 4-(2-cyclopropyl-2-((5-phenyloxazol-2- yl)amino)ethyl)piperidine-1 -carboxylate Example 171 : tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-(propylamino)-1 ,3,4- oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

Example 172: 5-methyl-N-(1 -phenyl-2-(1 -(3,3,3-trifluoropropanoyl)piperidin-4- yl)ethyl)thiophene-2-carboxamide

Example 173: methyl 4-(2-(4-fluorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 174: tert-butyl 4-(2-(4-fluorobenzamido)-2-(6-methylpyridin-3-yl)ethyl)piper idine- 1 -carboxylate

Example 175: tert-butyl 4-(2-(benzo[d][1 ,3]dioxole-5-carboxamido)-2- phenylethyl)piperidine-1 -carboxylate

Example 176: tert-butyl 4-(2-(1 -benzyl-6-oxo-1 ,6-dihydropyridin-3-yl)-2-(4- fluorobenzamido)ethyl)piperidine-1 -carboxylate

Example 177: (R)-ethyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine-1 -carboxylate

Example 178: tert-butyl 4-(2-(4-(methylthio)benzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 179: tert-butyl 4-(2-(4-methylthiophene-2-carboxamido)-2-phenylethyl)piperid ine- 1 -carboxylate

Example 180: tert-butyl 4-(2-phenyl-2-(5-vinylthiophene-2-carboxamido)ethyl)piperidi ne-1 - carboxylate

Example 181 : tert-butyl 4-(2-(1 H-indole-7-carboxamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 182: tert-butyl 4-(2-(benzo[b]thiophene-2-carboxamido)-2-phenylethyl)piperid ine- 1 -carboxylate

Example 183: (R)-tert-butyl 4-(2-(4-fluorobenzamido)-2-(6-methoxypyridin-3- yl)ethyl)piperidine-1 -carbox late

Example 184: 4-(2-(4-chlorobenzamido)-2-phenylethyl)-N-isopropylpiperidin e-1 carboxamide

Example 185: oxetan-3-yl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1- carboxylate

Example 186: tetrahydro-2H-pyran-4-yl 4-(2-(4-chlorobenzamido)-2- phenylethyl)piperidine-1-carbox late

Example 187: neopentyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 188: (R)-isopropyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine-1-carboxylate

Example 189: tert-butyl 4-(2- 6-cyanonicotinamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 190: tert-butyl 4-(2-(cyclohexanecarboxamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 191 : tert-butyl 4-(2-(2-methylthiazole-5-carboxamido)-2-phenylethyl)piperidi ne-1 - carboxylate

Example 192: tert-butyl 4-(2-phenyl-2-(4-propoxybenzamido)ethyl)piperidine-1 -carboxylate

Example 193: 4-chloro-N-(2-(1 -(cyclopentylsulfonyl)piperidin-4-yl)-1 - phenylethyl)benzamide

Example 194: tert-butyl 4-(2-(2-hydroxybenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 195: tert-butyl 4-(2- 4-hydroxybenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 196: tert-butyl 4-(2-(3-fluoro-4-hydroxybenzamido)-2-phenylethyl)piperidine- 1 - carboxylate

Example 197: 4-chloro-N-(1 -phenyl-2-(1-(piperidin-1-ylsulfonyl)piperidin-4- yl)ethyl)benzamide

Example 198: tert-butyl 4-(2-(3-cyclopentyl-1 ,2,4-oxadiazol-5-yl)-2-(4- fluorobenzamido)ethyl)piperidine-1-carbox late

Example 199: tert-butyl 4-(2-(3-chlorobenzamido)-2-phenylethyl)piperidine-1-carboxyl ate

Example 200: tert-butyl 4-(2-(3-(4-fluorophenyl)ureido)-2-phenylethyl)piperidine-1- carboxylate

Example 201 : tert-butyl 4-(2-(bicyclo[2.2.2]octane-1 -carboxamido)-2- phenylethyl)piperidine-1-carboxylate

Example 202: tert-butyl 4-(2-(4-fluorobenzamido)-2-(6-(2-methoxyethoxy)pyridin-3- yl)ethyl)piperidine-1 -carbox late

Example 203: tert-butyl 4-(2-(3-chloro-4-fluorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 204: tert-butyl 4-(2-(5-methylfuran-2-carboxamido)-2-phenylethyl)piperidine- 1- carboxylate

Example 205: tert-butyl 4-(2-(3,4-dichlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 206: (R)-methyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine-1 -carboxylate

Example 207: tert-butyl 4-(2-(4-fluorobenzamido)-2-(pyridin-3-yl)ethyl)piperidine-1 - carboxylate

Example 208: tert-butyl 4-(2-(4-fluorobenzamido)-2-(pyridin-4-yl)ethyl)piperidine-1- carboxylate

Example 209: tert-butyl 4-(2-(cycloheptanecarboxamido)-2-phenylethyl)piperidine-1- carboxylate

Example 210: tert-butyl 4-(2-(3,3-dimethylbutanamido)-2-phenylethyl)piperidine-1- carboxylate

Example 211 : tert-butyl 4-(2-(2,5-difluorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 212: tert-butyl 4-(2-(4-isopropylbenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 213: tert-butyl 4-(2-(4-fluoro-3-methylbenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 214: (R)-tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2- cyclopropylethyl)piperidine- -carboxylate

Example 215: 4-chloro-N-(1 -phenyl-2-(1 -(phenylsulfonyl)piperidin-4-yl)ethyl)benzamide

Example 216: tert-butyl 4-(2-(3-methoxybenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 217: tert-butyl 4-(2-(6-methylnicotinamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 218: tert-butyl 4-(2-(2-fluoro-4-methylbenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 219: tert-butyl 4-(2-(2-fluorobenzamido)-2-phenylethyl)piperidine-1 -carboxylate

I 1 O F Example 220: tert-butyl 4-(2-phenyl-2-(1 H-pyrrole-2-carboxamido)ethyl)piperidine-1 - carboxylate

Example 221 : tert-butyl 4-(2-(5-cyclopropyl-1 ,3,4-oxadiazol-2-yl)-2-(4- fluorobenzamido)ethyl)piperidine-1 -carbox late

Example 222: N-(2-(1 -acetylpiperidin-4-yl)-1 -phenylethyl)-4-chlorobenzamide

Example 223: tert-butyl 4-(2-(4-fluorobenzamido)-2-(5-isopropyl-1 ,3,4-oxadiazol-2- yl)ethyl)piperidine-1 -carboxylate

Example 224: tert-butyl 4-(2-(5-chlorothiophene-2-carboxamido)-2-(5-oxo-4,5-dihydro-

1 ,3,4-oxadiazol-2-yl)ethyl)piperidine-1 -carboxylate

Example 225: tert-butyl 4-(2-(4-fluorobenzamido)-3-(isobutylamino)propyl)piperidine- 1- carboxylate

Example 226: tert-butyl 4-(2-(4-fluorobenzamido)-2-(pyridin-2-yl)ethyl)piperidine-1- carboxylate

Example 227: tert-butyl 4-(2-(5-isobutylthiophene-2-carboxamido)-2- phenylethyl)piperidine-1 -carbox late

Example 228: tert-butyl 4-(2-(furan-2-carboxamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 229: (S)-tert- butyl 4-(2-((2-chloropyrimidin-4-yl)amino)-2- cyclopropylethyl)piperidine-1 -carbox late

Example 230: 4-chloro-N-(1 -phenyl-2-(1 -(piperidine-1 -carbonyl)piperidin-4- yl)ethyl)benzamide

Example 231 : (S)-tert- butyl 4-(2-(5-chlorothiophene-2-carboxamido)-4- (ethylamino)butyl)piperidine- -carboxylate

Example 232: tert-butyl 4-(2-(cyclopentanecarboxamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 233: tert-butyl 4-(2-(4-methylcyclohexanecarboxamido)-2-phenylethyl)piperidi ne- 1 -carboxylate

Example 234: (R)-tert-butyl 4-(2-(4-chlorobenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 235: tert-butyl 4-(2-(4-fluorobenzamido)-3-((2- methoxyethyl)amino)propyl) iperidine-1 -carboxylate

Example 236: tert-butyl 4-(2-(nicotinamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 237: 4-fluoro-N-(2-(1 -(3-methoxypropanoyl)piperidir

phenylethyl)benzamide

Example 238: 4-fluoro-N-(2-(1 -(3-methoxybutanoyl)piperidi

phenylethyl)benzamide

Example 239: tert-butyl 4-(2-(4-fluorobenzamido)-2-(5-methyloxazol-2-yl)ethyl)piperi dine- 1 -carboxylate

Example 240: tert-butyl 4-(2-(1 -methylcyclohexanecarboxamido)-2-phenylethyl)piperidine- 1 -carboxylate

Example 241 : tert-butyl 4-(2-(4-isopropoxybenzamido)-2-phenylethyl)piperidine-1 - carboxylate

Example 242: tert-butyl 4-(2-(4-isobutylbenzamido)-2-phenylethyl)piperidine-1 -carboxylate

Example 243: 4-chloro-N-(2-(1 -(morpholine-4-carbonyl)piperidi

phenylethyl)benzamide

Example 244: 2-((5-(2-(1 -(tert-butoxycarbonyl)piperidin-4-yl)-1 -(5-chlorothiophene-2- carboxamido)ethyl)-1 ,3,4-oxadiazol-2-yl)(methyl)amino)acetic acid

Example 245: (S)-tert- butyl 4-(2-((5-chloropyridin-2-yl)amino)-2- cyclopropylethyl)piperidine-1 -carbox late

PBMC IDQ1 assay:

Data shown in Table 1 . Compounds of the present invention were tested via high- throughput cellular assays utilizing detection of kynurenine via mass spectrometry and cytotoxicity as end-points. For the mass spectrometry and cytotoxicity assays, human peripheral blood mononuclear cells (PBMC) (PB003F; AllCells ^® , Alameda, CA) were stimulated with human interferon-γ (IFN-γ) (Sigma-Aldrich Corporation, St. Louis, MO) and lipopolysaccharide from Salmonella minnesota (LPS) (Invivogen, San Diego, CA) to induce the expression of indoleamine 2, 3-dioxygenase (ID01 ). Compounds with ID01 inhibitory properties decreased the amount of kynurenine produced by the cells via the tryptophan catabolic pathway. Cellular toxicity due to the effect of compound treatment was measured using CellTiter-Glo ^® reagent (CTG) (Promega Corporation, Madison, Wl), which is based on luminescent detection of ATP, an indicator of metabolically active cells.

In preparation for the assays, test compounds were serially diluted 3-fold in DMSO from a typical top concentration of 5 mM and plated at 0.5 μΙ_ in 384-well, polystyrene, clear bottom, tissue culture treated plates with lids (Greiner Bio-One, Kremsmiinster, Austria) to generate 11 -point dose response curves. Low control wells (0% kynurenine or 100% cytotoxicity) contained either 0.5 μί of DMSO in the presence of unstimulated (-IFN-y/- LPS) PBMCs for the mass spectrometry assay or 0.5 μί of DMSO in the absence of cells for the cytotoxicity assay, and high control wells (100% kynurenine or 0% cytotoxicity) contained 0.5 μΙ_ of DMSO in the presence of stimulated (+IFN-y/+LPS) PBMCs for both the mass spectrometry and cytotoxicity assays.

Frozen stocks of PBMCs were washed and recovered in RPMI 1640 medium (Thermo Fisher Scientific, Inc., Waltham, MA) supplemented with 10% v/v heat-inactivated fetal bovine serum (FBS) (Thermo Fisher Scientific, Inc., Waltham, MA), and 1X penicillin- streptomycin antibiotic solution (Thermo Fisher Scientific, Inc., Waltham, MA). The cells were diluted to 1 ,000,000 cells/mL in the supplemented RPMI 1640 medium. 50 μΙ_ of either the cell suspension, for the mass spectrometry assay, or medium alone, for the cytotoxicity assay, were added to the low control wells, on the previously prepared 384- well compound plates, resulting in 50,000 cells/well or 0 cells/well respectively. IFN-γ and LPS were added to the remaining cell suspension at final concentrations of 100 ng/ml and 50 ng/ml respectively, and 50 of the stimulated cells were added to all remaining wells on the 384-well compound plates. The plates, with lids, were then placed in a 37 °C, 5% C0 ₂ humidified incubator for 2 days. Following incubation, the 384-well plates were removed from the incubator and allowed to equilibrate to room temperature for 30 minutes. For the cytotoxicity assay, CellTiter-Glo ^® was prepared according to the manufacturer's instructions, and 40 μΙ_ were added to each plate well. After a twenty minute incubation at room temperature, luminescence was read on an EnVision ^® Multilabel Reader (PerkinElmer Inc., Waltham, MA). For the mass spectrometry assay, 10 μΙ_ of supernatant from each well of the compound-treated plates were added to 40 μΙ_ of acetonitrile, containing 10μΜ of an internal standard for normalization, in 384-well, polypropylene, V-bottom plates (Greiner Bio-One,

Kremsmiinster, Austria) to extract the organic analytes. Following centrifugation at 2000 rpm for 10 minutes, 10 μΙ_ from each well of the acetonitrile extraction plates were added to 90 μΙ_ of sterile, distilled H2O in 384-well, polypropylene, V-bottom plates for analysis of kynurenine and the internal standard on the RapidFire 300 (Agilent Technologies, Santa Clara, CA) and 4000 QTRAP MS (SCIEX, Framingham, MA). MS data were integrated using Agilent Technologies' RapidFire Integrator software, and data were normalized for analysis as a ratio of kynurenine to the internal standard.

The data for dose responses in the mass spectrometry assay were plotted as % ID01 inhibition versus compound concentration following normalization using the formula 100- (100*((U-C2)/(C1 -C2))), where U was the unknown value, C1 was the average of the high (100% kynurenine; 0% inhibition) control wells and C2 was the average of the low (0% kynurenine; 100% inhibition) control wells. The data for dose responses in the cytotoxicity assay were plotted as % cytotoxicity versus compound concentration following normalization using the formula 100-(100*((U-C2)/(C1 -C2))), where U was the unknown value, C1 was the average of the high (0% cytotoxicity) control wells and C2 was the average of the low (100% cytotoxicity) control wells.

Curve fitting was performed with the equation y=A+((B-A)/(1 +(10 ^x /10 ^c ) ^D )), where A was the minimum response, B was the maximum response, C was the log(XC ₅ o) and D was the Hill slope. The results for each test compound were recorded as plC50 values for the mass spectrometry assay and as pCC50 values for the cytoxicity assay (-C in the above equation).

Table 1

ID01 PBMC

example

pICso

1 8.1

2 8.1

3 8.0

4 8.4

5 8.1

6 8.0

7 8.2

8 8.2

9 8.3

10 8.3

1 1 8.3

12 8.5

13 8.1

14 8.4

15 8.4

16 9.1

17 8.1

18 8.2

19 8.4

20 8.7

21 8.8

22 8.7

23 8.4

24 8.5

25 8.5

26 8.1

27 8.0

28 8.1

29 8.8

30 8.0

31 8.1

32 8.0

33 8.1

34 8.4 ID01 PBMC example

pICso

35 8.2

36 8.8

37 8.6

38 8.3

39 8.3

40 8.4

41 8.4

42 8.3

43 9.0

44 8.5

45 8.5

46 8.4

47 8.4

48 8.4

49 8.2

50 8.2

51 8.1

52 8.0

53 8.5

54 7.9

55 7.9

56 7.9

57 7.9

58 7.9

59 7.9

60 7.9

61 7.9

62 7.9

63 7.9

64 7.9

65 7.9

66 7.9

67 7.9

68 7.8

69 7.8

70 7.8

71 7.8

72 7.8

73 7.8

74 7.8 ID01 PBMC example

pICso

75 7.8

76 7.8

77 7.8

78 7.8

79 7.8

80 7.8

81 7.8

82 7.8

83 7.8

84 7.7

85 7.7

86 7.7

87 7.7

88 7.7

89 7.7

90 7.7

91 7.7

92 7.7

93 7.7

94 7.7

95 7.7

96 7.7

97 7.6

98 7.6

99 7.6

100 7.6

101 7.6

102 7.6

103 7.6

104 7.6

105 7.6

106 7.6

107 7.5

108 7.5

109 7.5

110 7.5

111 7.5

112 7.5

113 7.5

114 7.5 ID01 PBMC example

pICso

1 15 7.5

1 16 7.5

1 17 7.5

1 18 7.5

1 19 7.5

120 7.4

121 7.4

122 7.4

123 7.4

124 7.4

125 7.4

126 7.4

127 7.4

128 7.4

129 7.4

130 7.3

131 7.3

132 7.3

133 7.3

134 7.3

135 7.3

136 7.3

137 7.3

138 7.2

139 7.2

140 7.2

141 7.2

142 7.2

143 7.1

144 7.1

145 7.1

146 7.1

147 7.1

148 7.1

149 7.1

150 7.1

151 7.1

152 7.1

153 7.1

154 7.1 ID01 PBMC example

pICso

155 7.1

156 7.1

157 7.0

158 7.0

159 7.0

160 7.0

161 7.0

162 7.0

163 7.0

164 7.0

165 7.0

166 7.0

167 7.0

168 7.0

169 7.0

170 7.0

171 7.0

172 7.0

173 6.9

174 6.9

175 6.9

176 6.9

177 6.9

178 6.9

179 6.9

180 6.9

181 6.8

182 6.8

183 6.8

184 6.8

185 6.8

186 6.8

187 6.8

188 6.8

189 6.7

190 6.7

191 6.7

192 6.7

193 6.7

194 6.6 ID01 PBMC example

pICso

195 6.6

196 6.6

197 6.6

198 6.6

199 6.5

200 6.5

201 6.5

202 6.5

203 6.5

204 6.5

205 6.5

206 6.5

207 6.4

208 6.4

209 6.4

210 6.4

21 1 6.4

212 6.4

213 6.4

214 6.4

215 6.4

216 6.3

217 6.3

218 6.3

219 6.3

220 6.3

221 6.3

222 6.3

223 6.3

224 6.3

225 6.3

226 6.2

227 6.2

228 6.2

229 6.2

230 6.2

231 6.2

232 6.1

233 6.1

234 6.1 ID01 PBMC example

pICso

235 6.1

236 6.0

237 6.0

238 6.0

239 6.0

240 6.0

241 6.0

242 6.0

243 6.0

244 6.0

245 6.0