Title of Invention: ALPHA-AMINO AMIDE DERIVATIVES

Technical Field

This invention relates to novel alpha-amino amide derivatives or salts thereof, which exhibit an activity for inhibiting uridyldiphospho(UDP)-3-0-acyl-N-acetylglucosamine deacetylase (LpxC) and antimicrobial pharmaceuticals comprising the same.

Background Art

Gram-negative bacteria have an outer membrane composed of a lipid bilayer inexistent in gram-positive bacteria, and thus are more resistant to drugs, as compared with gram-positive bacteria, due to the problem of drug permeability. Gram-negative bacteria are also known to have a plurality of drug efflux proteins, which are known to be involved in drug resistance (Non-Patent Document 1). Furthermore, lipopolysaccharide (LPS), one of the main constituents of the outer membrane, is involved in toxicity as an endotoxin.

Among gram-negative bacteria, Pseudomonas aeruginosa, in particular, has a strong tendency to show natural resistance to various antimicrobial agents. In recent years,

Pseudomonas aeruginosa strains, which has gained resistance to carbapenem drugs, quinolone drugs or aminoglycoside drugs, has been clinically isolated in medical settings (Non-Patent Document 2). Moreover, multi-drug resistant Pseudomonas aeruginosa which has obtained resistance to all of these three types of drugs has been isolated (Non-Patent Document 3). Emergence of multi-drug resistant Pseudomonas aeruginosa has become a major healthcare problem worldwide, because there have been few useful therapeutic drugs. Hence, there is a keen demand for the development of a drug having a novel mechanism of action.

UDP-3-O-acyl-N-acetylglucosamine deacetylase (LpxC) is an enzyme in charge of the synthesis of lipid A (hydrophobic anchor of LPS which is the constituent of the outer membrane). Lipid A biosynthesis consists of reactions in ten stages, and LpxC catalyzes the second stage of the biosynthesis reactions to remove the acetyl group of UDP-3-O-acyl-N- acetylglucosamine (Non-Patent Document 4). Lipid A is a component essential for the formation of the outer membrane, and is consequently indispensable for the survival of gram- negative bacteria (Non-Patent Document 5). LpxC is a rate-determining enzyme in the process of lipid A biosynthesis, and is an indispensable enzyme for lipid A biosynthesis. Thus, a drug inhibiting the activity of LpxC is highly expected to be an antimicrobial agent effective against gram-negative bacteria including Pseudomonas aeruginosa, particularly against drug resistant Pseudomonas aeruginosa and other gram-negative bacteria, because such a drug has a mechanism of action different from those of conventional drugs.

LpxC has been the focus of several pharmaceutical drug development programs over the last decade. LpxC has the catalytic zinc ion in its active site and many of the potent LpxC inhibitors identified so far contain a zinc-binding hydroxamic acid group. The Non-Patent Documents 6 and 7 summarize reported hydroxamic acid LpxC inhibitors. However, the hydroxamic acid group has been found to cause several problems associated with off-target toxicities and poor pharmacokinetics properties. All previous attempts to solve the problems have turned out unsuccessful.

Very few LpxC inhibitors are known that do not contain a hydroxamic acid group. Cohen's group reported LpxC inhibitors that contain a kojic acid group instead of a hydroxamic acid group. They also presented a non-hydroxamic acid LpxC inhibitor at the ASM Microbe 2016 / ICAAC2016 poster No. LB-056 but its chemical structure is not disclosed.

Thus there is an urgent need for a novel and effective antibacterial drug that does not contain a hydroxamic acid group and which works with a novel mechanism of action.

Citation List

Patent Documents

Patent Document 1 : International Publication 15/085238 pamphlet.

Non-Patent Documents

Non-Patent Document 1 : Antimicrobial Resistance (2002) Mar 1, 34, pp. 634-640.

Non-Patent Document 2: J. Antimicrob. Chemother. (2003) Jan 14, 51, pp. 347-352.

Non-Patent Document 3: J Hosp Med. (2013) Sep 10, 8, pp. 559-563.

Non-Patent Document 4: J. Biol. Chem. (1995) Dec 22, 270, pp. 30384-30391.

Non-Patent Document 5: J. Bacteriol. (1987), 169, pp. 5408-5415.

Non-Patent Document 6: Cold Spring Harb Perspect Med. (2016), July 1 ; 6(7), a025304.

Non-Patent Document 7: Curr Top Med Chem. (2016) 16(21), pp. 2379-2430.

Summary of Invention

Technical Problems

An object of the present invention is to find novel compounds that do not contain a hydroxamic acid group and inhibit LpxC or pharmaceutically acceptable salts thereof, and provide new pharmaceutical drugs that exhibit antimicrobial activity against gram-negative bacteria including Pseudomonas aeruginosa and their drug resistant strains and that are useful in treating bacterial infections.

Solution to Problems

The present inventors have conducted in-depth studies in an attempt to find out a compound having LpxC-inhibiting activity. As a result, they have found that a non-hydroxamic acid compound represented by the following general formula [1] or a pharmaceutically acceptable salt thereof attains the above object. Based on this finding, they have accomplished the present invention. The present invention will be described below. The present invention provides (1) A compound represented by the following general formula [1] or a pharmaceutically acceptable salt thereof:

[1]

wherein

X re resents a group selected from the followin formul

Y represents a group selected from the following formula [3]:

R ¹ represents a group selected from the following formula [4]:

C _1-4 alk

L represents a bond or a C alkylene group, R ² represents a phenyl group or a halogen atom,

R ³ represents a group selected from the following formula [5] :

wherein the phenylene group represented by formula [5] may be substituted with a halog atom,

L ³ represents a C alkylene group, a C alkynylene group, -0-, -OCH2-, -CH2O-, a bond,

R ⁴ represents a group selected from the following formula [6] :

L ⁴ represents -C≡C-, a CM alkylene group or a bond,

R ⁵ represents a group selected from the following formula [7]

W- /)—L ⁵ - ^* Halogen— ^*

^ [7],

L ⁵ represents -C≡C ^~ , a CM alkylene group or a bond,

R ⁶ represents a group selected from the following formula [8]:

L ⁶ represents ^~ C≡C-, a C _1-4 alkylene group or a bond, and

W represents a hydrogen atom, a halogen atom, a phenyl group, a CM hydroxyalkyl group, HOCH ₂ CH ₂ 0- HOOC-CH2CH2- or N-morpholinomethyl group, n represents 1 or 2, and * indicates the site of the attachment of a moiety;

(I),

wherein R ¹ , R ³ , R ⁴ and R ⁵ are as defined in item (1).

(3) The compound or the pharmaceutically acceptable salt thereof, according to item (1) or (2), wherein Y is selected from the following formula [3a]:

(4) The compound or the pharmaceutically acceptable salt thereof, according to item (3), wherein Y is selected from the following formula [3 b]: Me [3b];

(5) The compound or the pharmaceutically acceptable salt thereof, according to any one of items (1 ) to (4), wherein R ¹ is selected from the following formula [4] :

wherein W is as defined in item (1).

(6) The compound or the pharmaceutically acceptable salt thereof, according to item (1), wherein X is selected from the following formula [2b]: [2b],

wherein R ⁶ is as defined in item (1)

[3c];

(7) A pharmaceutical composition comprising the compound or the pharmaceutically acceptable salt thereof according to any one of items (1) to (6);

(8) An LpxC inhibitor comprising the compound or the pharmaceutically acceptable salt thereof according to any one of items (1) to (6).

(9) An antimicrobial agent comprising the compound or the pharmaceutically

acceptable salt thereof according to any one of items (1) to (6).

Advantageous Effects of Invention

The compound or the pharmaceutically acceptable salt thereof according to the present invention has a strong LpxC-inhibiting action. Thus, the compound or its pharmaceutically acceptable salt is useful as a pharmaceutical composition and as an antimicrobial agent against gram-negative bacteria. Description of Embodiments

The present invention will be described in further detail below. The terms and phrases used herein will be explained first.

In the present invention, "n-" means normal, "i-" iso, "sec-" secondary, "tert-" tertiary, "c-" cyclo, "o-" ortho, "m-" meta, and "p-" para.

The "halogen atom" means a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The "C _M alkyl group" refers to a straight-chain or branched-chain alkyl group having 1 to 4 carbon atoms. Its examples are a methyl group, an ethyl group, a n-propyl group, a n-butyl group, an isopropyl group, an isobutyl group, a tert-butyl group and a sec-butyl group.

The "C _2-4 alkynyl group" refers to a straight-chain or branched-chain alkynyl group with 2 to 4 carbon atoms which has one or more triple bonds at any position(s) of the above-mentioned "d- ₈ alkyl group". Its examples are an ethynyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynyl group and a 3-butynyl group.

The "C _M hydroxyalkyl group" refers to an alkyl group in which one or more of the hydrogen atoms of the above-mentioned "CM alkyl group" has been or have been substituted with a hydroxyl group or hydroxyl groups. Its examples are a hydroxymethyl group, a 1 - hydroxyethyl group, a 2-hydroxyethyl group, a 2-hydroxypropyl group, a 3-hydroxypropyl group, a 1-hydroxybutyl group, a 2-hydroxybutyl group, a 3-hydroxybutyl group and a 4- hydroxybutyl group.

The "C _M alkylene group" refers to a straight-chain or branched-chain alkylene group having 1 to 4 carbon atoms. Its examples are -CH ₂ -, -(CH ₂ ) ₂ -, -(CH ₂ ) ₃ -, -CH ₂ -CH(CH ₃ , -C(CH ₃ ) ₂ -, -(CH ₂ ) ₄ -, -(CH ₂ ) ₂ -CH(CH ₃ )-, -CH ₂ -CH(CH ₃ )-CH ₂ - and -CH(CH ₃ )-(CH ₂ ) ₂ -.

The "C _2- 4 alkynylene group" refers to a straight-chain or branched-chain alkynylene group having 2 to 4 carbon atoms which has one or more triple bonds in the chain.

The "protecting group for an amino group" include all groups usable usually as protecting groups for an amino group, and includes, for example, the groups described in P.G.M. Wuts et al., Protective Groups in Organic Synthesis, 5th Ed., 2014, John Wiley Sons, Inc.

The "leaving group" includes, for example, a halogen atom, a methnesulfonyloxy group, a ethanesulfonyloxy group, a isopropanesulfonyloxy group, a trifluoromethanesulfonyloxy group, benzensulfonyloxy group and a p-toluenesulfonyloxy group.

The "antimicrobial agent" refers to a substance which has the ability to act on bacteria, such as gram-positive bacteria or gram-negative bacteria, thereby suppressing their growth or destroying them. The antimicrobial agent may be one which keeps down propagation of bacteria, or kills some of bacteria to decrease their count. Examples of gram-positive bacteria are the genus Staphylococcus (Staphylococcus aureus, Staphylococcus epidermidis, etc.), the genus Streptococcus (Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus pneumoniae, etc.), and the genus Enterococcus (Enterococcus faecalis, Enterococcus faecium, etc.). Examples of gram-negative bacteria are the genus Pseudomonas (Pseudomonas aeruginosa, etc.), the genus Escherichia (Escherichia coli, etc.), the genus Klebsiella

(Klebsiella pneumoniae, Klebsiella oxytoca, etc.), the genus Haemophilus (Haemophilus influenzae, Haemophilus parainfluenzae, etc.), the genus Bordetella (Bordetella pertussis, Bordetella bronchi septica, etc.), the genus Serratia (Serratia marcescens, etc.), the genus Proteus (Proteus mirabilis, etc.), the genus Enterobacter (Enterobacter cloacae, etc.), the genus Campylobacter (Campylobacter jejuni, etc.), the genus Citrobacter, the genus Vibrio (Vibrio parahaemolyticus, Vibrio cholerae, etc.), the genus Morganella (Morganella morganii, etc.), the genus Salmonella (Salmonella typhi, Salmonella paratyphi, etc.), the genus Shigella (Shigella dysenteriae, etc.), the genus Acinetobacter (Acinetobacter baumannii,

Acinetobacter calcoaceticus, etc.), the genus Legionella (Legionella pneumophila, etc.), the genus Bacteroides (Bacteroides fragilis, etc.), the genus Neisseria (Neisseria gonorrhoeae, Neisseria meningitides, etc.), the genus Moraxella (Moraxella catarrhalis, etc.), the genus Chlamydia (Chlamydia trachomatis, Chlamydia psittaci, etc.), and the genus Helicobacter (Helicobacter pylori, etc.).

The preferred embodiments of the compound according to the present invention are as follows:

Preferred X is a rou represented by the followin formula 2a] :

wherein R ¹ , R ³ , R ⁴ and R ⁵ are defined above,

s a group represented by the following formula:

wherein R is defined above.

Preferred Y is a group represented b the following formula 3a]

more preferred X is a group represented by the following formula [3b]:

[3b], and the most preferred X is a group represented by the following formula:

Preferred R is a group represented by the following formula [4]:

where the definition of W is described above. Preferred W is a hydrogen atom, a C _1-4 hydroxyalkyl group, HOCH ₂ CH ₂ 0- or N-morpholinomethyl group.

A preferred sent invention is as follows

[9]

where the definition and preferred embodiment of W are described above.

The compounds represented by the formula [1] of the present invention have asymmetric carbon at alpha-carbon atom. The compounds of the present invention may be used in racemic form or as a specific enantiomer. As the specific enantiomer, the compounds represented by the following formula [10] are preferred:

where the definitions and preferred forms of X and Y are described previously.

The compounds of the present invention can exist as tautomers, stereoisomers such as geometrical isomers, and optical isomers, and the present invention includes them. The present invention also includes various hydrates, solvates and polymorphic substances of the compounds of the invention and their salts.

In the present invention, the pharmaceutically acceptable salts refer to salts which are used in chemotherapy and prevention of bacterial infections. Their examples are salts with acids such as formic acid, acetic acid, propionic acid, butyric acid, trifluoroacetic acid, maleic acid, tartaric acid, citric acid, stearic acid, succinic acid, ethylsuccinic acid, malonic acid, lactobionic acid, gluconic acid, glucoheptonic acid, benzoic acid, methanesulfonic acid, ethanesulfonic acid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid (tosic acid), laurylsulfuric acid, malic acid, aspartic acid, glutamic acid, adipic acid, hydrochloric acid, hydrobromic acid, phosphoric acid, sulfuric acid, hydriodic acid, nicotinic acid, oxalic acid, picric acid, thiocyanic acid, undecanoic acid, acrylic polymer, and carboxyvinyl polymer; salts with inorganic bases such as lithium salt, sodium salt, potassium salt, magnesium salt and calcium salt; salts with organic amines such as morpholine and piperidine; and salts with amino acids. For reference see for example "Handbook of

Pharmaceutical Salts. Properties, Selection and Use." P. Heinrich Stahl, Camille G. Wermuth (Eds.), Wiley- VCH (2008).

The compound of the present invention can be made into a medicinal preparation upon combination with one or more pharmaceutically acceptable carriers, excipients or diluents. Examples of such carriers, excipients and diluents include water, lactose, dextrose, fructose, sucrose, sorbitol, mannitol, polyethylene glycol, propylene glycol, starch, gum, gelatin, alginate, calcium silicate, calcium phosphate, cellulose, aqueous syrup, methyl cellulose, polyvinyl pyrrolidone, alkylparahydroxybenzosorbate, talc, magnesium stearate, stearic acid, glycerin, sesame oil, olive oil, soy oil, and various other seed oils. Moreover, the above carriers, excipients or diluents can be mixed, as needed, with commonly used additives such as thickeners, binders, disintegrants, pH regulators, and solvents, and can be prepared as an oral or parenteral drug, such as tablets, pills, capsules, granules, powders, liquids, emulsions, suspensions, ointments, injections, or skin patches, by a customary pharmaceutical technology.

The compound of the present invention can be administered intravenously, orally or parenterally to an adult patient in a dose of 10 to 5,000 mg as a single daily dose or as divided portions per day. This dose can be increased or decreased, as appropriate, according to the type of the disease to be treated, or the age, body weight, symptoms, etc. of the patient. The compound of the present invention can also be used in combination with other drugs. The compound of the present invention can be synthesized, for example, by methods to be shown below, but the present invention is in no way limited to these methods of

manufacturing the compound.

Scheme I:

(I-A) (l-B) (l-C) (l-D)

A compound represented by the general formula (I-A) (where R ^Ia -NH-R ^Ib is a compound represented in formula [2] defined above) is reacted with a compound represented by the general formula (I-B) (where R ^Ic is a hydroxyl group or a halogen atom, PG is a protecting group for an amino group, and Y is as defined above) in the presence of a condensing agent (in case R ^Ic is a hydroxyl group) and in the presence or absence of a base, whereby a compound represented by the general formula (I-C) can be obtained. Then, the compound represented by the general formula (I-C) is reacted under appropriate conditions in

accordance with the type of the protecting group PG, whereupon the compound represented by the general formula (I-D) can be obtained.

A compound having a benzylpiperidine group represented in formula [2] can be synthesized in the following scheme II.

Scheme II:

(ll-A) (ll-B)

A compound represented by the general formula (II-A) (where W is as defined above) is reacted with a compound represented by the general formula (II-B) (where R ^IIa is a leaving group, PG is a protecting group for an amino group, and the other symbol is as defined above) in the presence of catalysts, such as bis(triphenylphosphine)dichloropalladium and cupper iodide, in the presence or absence of a base, and in the presence or absence of a ligand, whereby a compound represented by the general formula (II-C) (where the symbols are as defined above) can be obtained. Then, the compound represented by the general formula (II- C) is reacted under appropriate conditions in accordance with the type of the protecting group PG, whereupon the compound represented by the general formula (II-D) can be obtained. A compound having the other group represented in formula [2] (a benzylidenepiperidine group substituted by R ² , an indoline group substituted by R ³ , a 1,2,3,4-tetrahydroisoquinoline group substituted by R ⁴ , a lH-indol-3 -amine group substituted by R ⁵ or an aniline group substituted by R ⁶ ) can be synthesized in the same manner as scheme II by replacing the compound of the general formula (II-B) with the corresponding compound.

In the methods of synthesis shown above, the sequence of the reaction steps can be changed as needed. If an amino group, a hydroxyl group, a formyl group, and a carboxy group are present in the compounds obtained in the respective reaction steps and their intermediates, the reactions can be performed, with the protective groups for them being removed for deprotection or being used in appropriately changed combinations.

Unless otherwise specified, examples of the base used in any of the above reactions are sodium carbonate, potassium carbonate, cesium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium acetate, potassium acetate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium methoxide, potassium tert-butoxide, sodium hydride, lithium hydride, triethylamine, diisopropylethylamine, dimethylaniline, diethylaniline, pyridine, pyrrolidine, and N-methylmorpholine.

Examples of the catalyst are palladium acetate, palladium chloride,

bis(triphenylphosphine)palladium(II) dichloride, tetrakis(triphenylphosphine)palladium, bis(acetonitrile)dichloropalladium, bis(benzonitrile)dichloropalladium,

tris(dibenzylideneacetone)dipalladium, bis(dibenzylideneacetone)palladium, 1 , Γ- bis(diphenylphosphino)ferrocenedichloropalladium,

bis(tricyclohexylphosphine)dichloropalladium, bis(tri-o-tolylphosphine)dichloropalladium, bis(tri-tert-butylphosphine)dichloropalladium, (1 ,3-bis(2,6- diisopropylphenyl)imidazolidene)(3-chloropyridyl)palladium(I I) dichloride, palladium on carbon, palladium hydroxide, and copper iodide.

Examples of the ligand are tri-tert-butylphosphine, tricyclohexylphosphine,

triphenylphosphine, tritolylphosphine, tributyl phosphite, tricyclohexyl phosphite, triphenyl phosphite, 1 , 1 '-bis(diphenylphosphino)ferrocene, 2,2'-bis(diphenylphosphino)- 1 , Γ- binaphthyl, 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, 2-dicyclohexylphosphino- 2',4',6'-triisopropylbiphenyl, 2-(di-tert-butylphosphino)-2',4',6'-triisopropylbiphenyl, and 2- (di-tert-butylphosphino)biphenyl.

The solvent is not limited, if it is stable under the reaction conditions concerned, is inert, and does not impede the reaction. Examples of the solvent are polar solvents (e.g., water and alcoholic solvents such as methanol, ethanol and isopropanol), inert solvents (e.g., halogenated hydrocarbon-based solvents such as chloroform, methylene chloride, dichloroethane and carbon tetrachloride, ether-based solvents such as diethyl ether, diisopropyl ether, tetrahydrofuran, 1 ,4-dioxane and dimethoxyethane, aprotic solvents such as dimethylformamide, dimethyl sulfoxide, ethyl acetate, tert-butyl acetate, acetonitrile and propionitrile, aromatics such as benzene, toluene and anisole, or hydrocarbons such as cyclohexane), and mixtures of these solvents.

The reaction can be performed at an appropriate temperature selected from a range of from -78°C to the boiling point of the solvent used in the reaction, at ordinary pressure or under pressurized conditions, and under microwave irradiation or the like.

Experimental Procedures

Herein below, the present invention will be described in further detail by examples of preparation of Intermediates, Compounds in the Examples, and Reference Compounds. The compounds of the present invention are in no way limited to the compounds described in the Examples presented below.

Unless otherwise described, the following conditions were used for compound synthesis, purification and analysis.

A microwave synthesizer Initiator ^"1" (Biotage) was used for a microwave reaction condition. OH-type silica gel column chromatography was performed using SNAP Ultra (Biotage) or using REVELERIS 40 μηι (Grace), and amino-type type silica gel chromatography was performed using SNAPCartridge ISOLUTE Flash-NH ₂ (Biotage) or Grace REVELERIS Amino 40 μπι (Grace). Preparative chromatography was performed using PLC Silica gel 60F254 (Merck), and amino-type preparative chromatography was performed using NH ₂ Silica Gel 60 F ₂₅₄ Plate- Wako (Wako).

The prep-HPLC purifications were performed using Agilent 1260 Infinity or Agilent 6130 (ionization method: Electron Spray Ionization (ESI)), and Agilent 385-ELSD were used when the ELSD detector was attached.

Columns: YMC-Acrus Triart C18, 5.0 μπι, Φ 30 x 50 mm.

Xbridge Prep CI 8, 5.0 μηι OBD, Φ 30 x 50 mm.

Waters XSlect CSH 5.0 μπι, Φ 30 x 50 mm.

Eluents: A(H ₂ 0 + 0.1 % HCOOH), B(CH ₃ CN + 0.1% HCOOH). ^"

One of the following conditions was used for purifications:

1. Flow rate 50mL/min; 0-0.5 min (A/B = 90/10), 0.5-7.5 min (A/B = 90/10-20/80, gradient), 7.5-7.95 min (A/B = 20/80), 7.95-8.0 min (A/B = 20/80-5/95, gradient), 8.0- 9.0 min (A/B = 5/95).

2. Flow rate 50mL/min; 0-0.5 min (A/B = 95/5), 0.5-7.5 min (A/B = 95/5-50/50, gradient), 7.5-7.95 min (A/B = 50/50), 7.95-8.0 min (A B = 50/50-5/95, gradient), 8.0-9.0 min (A/B = 5/95).

3. Flow rate 50mL/min; 0-0.5 min (A/B = 80/20), 0.5-7.0 min (A/B = 80/20-5/95, gradient), 7.0-7.45 min (A/B = 5/95), 7.45-7.5 min (A/B = 5/95-1/99, gradient), 7.5-9.0 min (A/B = 1/99).

4. Flow rate 40mL/min; 0-2.0 min (A/B = 90/10), 2.0-1 1.0 min (A/B = 90/10-20/80, gradient), 1 1.0-12.0 min (A/B = 20/80-5/95, gradient), 12.0-13.5 min (A/B = 5/95).

NMR spectra were run on JNM-ECA600 (600 MHz, JEOL), JNM-ECA500 (500 MHz, JEOL) or AVANCE III HD 400 (400 MHz, BRUKER). Chemical shifts for Ή NMR are reported in parts per million (ppm). Abbreviations used in the Ή NMR data are shown below, s: Singlet

br.s.: Broad singlet

d: Doublet

dd: Double doublet dt: Double triplet

t: Triplet

td: Triple doublet

tt: Triple triplet

q: Quartet

quin: Quintet

m: Multiplet

Mass spectra (MS) and the retention time (RT, minutes) were run on LC-MS systems with one of the following Methods and Conditions:

A Agilent 1290 Infinity for LC system, Agilent 6130 or 6150 for Quadrupole LC/MS system, and Agilent 385-ELSD when a ELSD detector is attached.

Column: ACQUITY CSH CI 8 (Waters), 1.7 μπι, Φ2.\ x 50 mm.

Ionization method: ESI.

Eluents: A(H ₂ 0 + 0.1 % HCOOH), B(CH ₃ CN + 0.1% HCOOH).

Flow rate: 0.8 mL/min.

Detection: 254nm, 210nm or ELSD.

Gradient: 0.0-0.8 min (A/B = 95/5-60/40), 0.8-1.08 min (A/B = 60/40-1/99), 1.08- 1.38 min (A B = 1/99).

B Equipment, column, ionization method, eluents, flow rate and detection are the same as condition 1.

Gradient: 0.0-1.2 min (A/B = 80/20-1/99), 1.2-1.4 min (A/B = 1/99).

C Equipment, column, ionization method, eluents, flow rate and detection are the same as condition 1.

Gradient: 0.0-0.8 min (A/B = 70/30-1/99), 0.8-1.4 min (A/B = 1/99).

D Equipment: LCMS-2010EV (Shimadzu).

Column: XR-ODS (Shimadzu), 2.2 μπι, Φ 2.0 x 30 mm.

Ionization method: ESI APCI (atmospheric pressure chemical ionization) dual source.

Eluents: A(H ₂ 0 + 0.1% HCOOH), B(CH ₃ CN + 0.1% HCOOH).

Flow rate: 0.6 mL/min.

Detection: 254nm or 210nm.

Gradient: 0.0-0.5 min (A/B = 90/10), 0.5-1.5 min (A/B = 90/10-60/40), 1.5-2.5 min (A/B = 60/40-1/99), 2.5-5.0 min (A/B = 1/99).

E Equipment; Agilent 1290 Infinity II series instrument connected to an Agilent TOF 6230 single quadrupole with a ESI source.

Column CI 8, Φ50 x 2.1 mm, 2.5 μιη (Phenomenex).

Eluents: A (H ₂ 0 + 10 mmol / ammonium formate + 0.08% (v/v) formic acid at pH ca 3.5), B (95% Acetonitrile + 5% A + 0.08% (v/v) formic acid).

Detection: 230 nm, 254 nm and 270 nm.

Gradient: 0.0-0.12 min (A/B = 95/5 flow 1.3 mL/min), 0.12-1.30 min (A/B = 95/5- 5/95 flow 1.3 mL /min), 1.30-1.35 min (A/B = 5/95 flow 1.3-1.6 mL/min), 1.35-1.85 min (A B = 5/95 flow 1.6 mL/min), 1.85-1.90 min (A/B = 5/95 flow 1.6-1.3 mL/min), 1.90- 1.95 min (A/B = 5/95-95/5 flow 1.3 mL/min).

Mass spectra (MS) were performed with the following conditions:

F Equipment: LCMS-IT-TOF (Shimadzu).

Ionization method: ESI/APCI (electrospray ionization / atmospheric pressure c hemical ionization) dual source.

Eluents: 90% CH ₃ OH.

Flow rate: 0.2 mL/min.

Chemical names of compounds in the Examples, Intermediates and Reference Compounds are generated by ACD/Name 2015 (ACD Labs 2015 LSM, Advanced Chemistry

Development Inc.,).

Abbreviations used in the Experimental procedures are shown below.

(+)-CSA: (+)-10-camphorsulfonic acid

APCI: Atmospheric pressure chemical ionization

aq.: Aqueous solution

Boc: t-Butoxycarbonyl

(Boc) ₂ 0: Di-tert-butyl dicarbonate

Bn: Benzyl

Bu: Butyl

BuOAc: n-Butyl acetate

CHC1 ₃ : Chloroform

Cs ₂ C0 ₃ : Cesium carbonate

Cul: Copper(I) iodide

DEAD: Diethyl azodicarboxylate

Dess-Martin Periodinane: 1,1 ,1 -Triacetoxy- 1 , 1 -dihydro- 1 ,2-benziodoxol-3 ( 1 H)-one DIPEA: N,N-diisopropylethylamine

DMAP: N,N-dimethyl-4-aminopyridine

DME: Dimethoxyethane

DMF: N,N-dimethylformamide

DMSO-d6: Hexadeuterodimethyl sulfoxide

DPP A: Diphenylphosphoryl azide

ee: Enantiomeric excess

ESI: Electrospray ionization Et: Ethyl

EtOAc: Ethyl acetate

EtOH: Ethanol

HATU: 0-(7-azabenzotriazol- 1 -yl)-N,N,N^N'-tetramethyluronium hexafluorophosphate HC1: Hydrochloride

HMDS: Hexamethyldisilazane

HOBt · H20: 1-Hydroxybenzotriazole monohydrate

IPA: Isopropyl alcohol

IPE: Diisopropyl ether

LC: Liquid chromatography

LDA: Lithium diisopropylamide

Me: Methyl

MeOH: Methanol

Ms: Methanesulfonyl

NaBH ₄ :Sodium tetrahydroborate

NaBH(OAc) ₃ : Sodium triacetoxyborohydride

NH ₄ C1: Ammonium chloride

NMM: 4-Methylmorphiline

NMP: l-Methyl-2-pyrrolidone

OTHP: l-Tetrahydropyran-2-yloxy

OTBDPS: Tert-butyldiphenylsilyloxy

OTBS: Tert-butyldimethylsilyloxy

OMs: Methanesulfonyloxy

OTs: 4-Methylbenzenesulfonyloxy

PEPPSI: (l,3-bis(2,6-diisopropylphenyl)imidazolidene)(3-chloropyridy l)palladium(II) dichloride

PdCb(dppf) CH2C12 : 1 , 1 -bi s(diphenylphosphino)ferrocenepalladium(II) chloride dichloromethane complex

PdCl ₂ (PPh ₃ ) ₂ : Bis(triphenylphosphine)palladium(II) dichloride

Pd(PPh ₃ ) ₄ : Tetrakis(triphenylphosphine)palladium(0)

PPh ₃ : Triphenylphosphine

PPTS: Pyridine 4-methylbenzenesulfonate

(p-Tol) ₃ P: Tri(4-methylphenyl)phosphine

p-TsOH: p-Toluenesulfonic acid

quant.: Quantitative yield

RT: Retention time (minutes) measured by LCMS

SFC: Supercritical Fluid Chromatography SUPERSTABLE PD(0) CATALYST: Tris{tris[3,5-bis(trifluoromethyl)phenyl]phosphine} palladium(O)

T3P: Propylphosphonic anhydride

TBAF: Tetra-n-butylammonium fluoride

TBDPS: Tert-butyldiphenylsilyl

TBS: Tert-butyldimethylsilyl

TEA: Triethylamine

TFA: Trifluoroacetic acid

THF: Tetrahydrofuran

THP: Tetrahydropyranyl

TMAD: 3-(Dimethylcarbamoylimino)-l,l-dimethylurea

TMS: Trimethylsilyl

TIPS: Triisopropylsilyl

TrCl : Triphenylmethyl chloride

Ts : 4-Methylbenzenesulfonyl

TsCl: 4-Methylbenzenesulfonyl chloride

WSC HCl: l-Ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride

Reference Compounds

Table 1. Reference Compound List. Reference Compound ID, chemical structures, MS data,

ND: not determined

'H-NHR of the Compounds without LCMS data are follows:

Reference Compound R-14: Ή NMR (400 MHz, METHANOL-d4) δ ppm 4.03 (s, 2 H), 7.32 (d, J=6.7 Hz, 1 H), 8.34 (dd, J=6.7, 1,2 Hz, 1 H), 9.43 (s, 1 H).

Reference Compound R-15: Ή NMR (400 MHz, DMSO-d6) δ ppm 3.92 (br d, J=5.0 Hz, 2 H), 8.08 - 8.18 (m, 3 H), 8.23 (br d, J=5.3 Hz, 1 H), 8.70 - 8.77 (m, 1 H), 9.96 (s, 1 H), 12.12 (br s, 1 H).

Reference Compound R-32: Ή NMR (400 MHz, METHANOL-d4) δ ppm 3.95 (s, 2 H), 6.83 (s, 1 H), 8.89 (s, 1 H).

Reference Compound R-76: Ή NMR (400 MHz, DEUTERIUM OXIDE) δ ppm 3.93 - 4.07 (m, 2 H), 4.18 (dd, J=5.6, 4.3 Hz, 1 H), 4.40 - 4.58 (m, 2 H), 7.10 (d, J=8.4 Hz, 2 H), 7.42 (d, J=8.2 Hz, 2 H), 7.62 (br d, J=8.4 Hz, 2 H), 7.66 (br d, J=8.2 Hz, 2 H).

Reference Compound R-77: ¾ NMR (400 MHz, DEUTERIUM OXIDE) δ ppm 3.91 - 4.03 (m, 2 H), 4.12 - 4.17 (m, 1 H), 4.44 (s, 2 H), 4.84 (q, J=8.6. Hz, 2 H), 7.03 (d, J=8.6 Hz, 1 H), 7.82 (dd, J=8.6, 2.4 Hz, 1 H), 8.09 (d, J=2.4 Hz, 1 H).

Reference Compound R-170: Ή NMR (400 MHz, METHANOL-d4) δ ppm 3.98 - 4.14 (m, 2 H), 4.19 - 4.32 (m, 1 H), 7.84 (d, J=6.5 Hz, 1 H), 8.10 (s, 1 H), 8.32 (br d, J=6.5 Hz, 1 H), 9.27 (br s, 1 H).

Reference Compound R-181 : Ή NMR (600 MHz, CHLOROFORM-d) δ ppm 4.70 (s, 2 H), 5.13 (s, 2 H), 6.94 (d, J=8.3 Hz, 2 H), 7.05 - 7.15 (m, 3 H), 7.35 - 7.38 (m, 2 H), 7.47 (s, 1 H). Reference Compound R-184: ¾ NMR (400 MHz, CHLOROFORM-d) δ ppm 3.43 (s, 3 H), 3.69 - 3.82 (m, 2 H), 3.91 - 3.96 (m, 1 H), 4.11 - 4.19 (m, 1 H), 4.21 - 4.31 (m, 1 H), 6.80 - 6.85 (m, 2 H), 6.94 - 6.97 (m, 1 H), 7.05 (s, 1 H), 7.19 - 7.31 (m, 2 H), 7.50 (s, 1 H).

Reference Compound R-186: Ή NMR (400 MHz, METHANOL-d4) δ ppm 4.31 (t, J=4.9 Hz, 2 H), 4.52 (t, J=4.9 Hz, 2 H), 6.92 (d, J=7.1 Hz, 2 H), 7.25 (d, J-7.1 Hz, 2 H), 7.83 (d, J=1.5 Hz, 1 H), 8.23 (d, J=1.5 Hz, 1 H).

Reference Compound R-193: Ή NMR (400 MHz, METHANOL-d4) δ ppm 2.13 (quin, J=7.4 Hz, 2 H), 2.54 - 2.67 (m, 2 H), 4.08 (t, J=7.1 Hz, 2 H), 7.10 (br s, 1 H), 7.14 - 7.22 (m, 2 H), 7.22 - 7.32 (m, 3 H).

Reference Compound R-215: ^l U NMR (400 MHz, CHLOROFORM-d) δ ppm 2.03 - 2.14 (m, 2 H), 2.59 (t, J=7.5 Hz, 2 H), 3.85 (t, J=7.0 Hz, 2 H), 6.41 (dd, J=8.3, 1.8 Hz, 1 H), 7,01 - 7.03 (m, 1 H), 7.05 - 7.10 (m, 2 H), 7.26 - 7.31 (m, 2 H). Chemical names of the Reference Compounds in Table- 1 are follows:

R-l : N-[3-(trifluoromethoxy)phenyl]glycinamide~ hydrochloride

R-2: N-[l,r-biphenyl]-3-ylglycinamide~ hydrochloride

R-3 : N-methyl-N-[3-(trifluoromethoxy)phenyl]glycinamide— hydrochloride

R-4 : N ² ,N ² -dimethyl-N- [3 -(trifluoromethoxy)phenyl] glycinamide— hydrochloride

R-5: 2-(4-ethylpiperazin-l-yl)-N-[3-(trifluoromethoxy)phenyl]acet amide~ hydrochloride R-6: 2-(morpholin-4-yl)-N-[3-(trifluoromethoxy)phenyl]acetamide

R-7 : N- {4'- [3 -(morpholin-4-yl)propoxy] [1,1 -biphenyl] -3 -yl } glycinamide— hydrochloride R-8 : 3 ,3 ,3-trifluoro-N- [3 -(trifluoromethoxy)phenyl] alaninamide

R-9: N-[3-(trifluoromethoxy)phenyl]-L-serinamide

R- 10 : N- [3 -(trifluoromethoxy)phenyl] -D-alpha-glutamine— hydrochloride

R- 1 1 : N- [3 -(trifluoromethoxy)phenyl]-D-histidinamide

R-12: 3-pyridin-4-yl-N-[3-(trifluoromethoxy)phenyl]-D-alaninamide~ 2 hydrochloride R-13: 3-pyridin-3-yl-N-[3-(trifluoromethoxy)phenyl]-D-alaninamide~ 2 hydrochloride R-l 4: N-(4-hydroxypyridin-3-yl)glycinamide— 2 hydrochloride

R-l 5: N-(5-bromo-4-hydroxypyridin-3-yl)glycinamide— 2 hydrochloride

R- 16 : N- [4-hydroxy-6-(trifluoromethyl)pyridin-3 -yl] glycinamide— hydrochloride

R-l 7: N-[3-(trifluoromethoxy)phenyl]-D-homoserinamide R-18: 2-amino-N ¹ -methyl-N ³ -[3-(trifluoromethoxy)phenyl]propanediamide~ hydrochloride R- 19: 2-amino-N ¹ - [3 -(trifluoromethoxy)phenyl]propanediamide— hydrochloride

R-20 : N- [3 -(trifluoromethoxy)pheny 1] -D-tyrosinamide— hydrochloride

R-21 : (2R)-2-amino-4-[(methanesulfonyl)amino]-N-[3-(trifluorometho xy)phenyl]butanarnide R-22: 3-pyridin-2-yl-N-[3-(trifluoromethoxy)phenyl]-L-alaninamide� �� 2 hydrochloride R-23: (2R)-2,4-diamino-N-[3-(trifluoromethoxy)phenyl]butanamide

R-24 : 1 - [(O-methyl-3 -oxoseryl)amino] -3 -(trifluoromethoxy)benzene-- hydrochloride R-25: N-(3-bromo-2-propylphenyl)-N-methylglycinamide~ hydrochloride

R-26 : (2R)-4-acetamido-2-amino-N- [3 -(trifluoromethoxy)phenyl]butanamide

R-27: N-lH-indol-3-ylglycinamide-- hydrochloride

R-28: N ⁵ -acetyl-N-[3-(trifluoromethoxy)phenyl]-D-ornithinamide

R-29: N-(4-hydroxy-5-methoxypyridin-3-yl)glycinamide~ 2 hydrochloride

R-30 : N ⁵ -(methanesulfonyl)-N- [3 -(trifluoromethoxy)phenyl]-D-ornithinamide~

hydrochloride

R-31 : N-[3-(trifluoromethoxy)phenyl]-D-ornithinamide

R-32: N-(6-chloro-4-hydroxypyridin-3-yl)glycinamide— 2 hydrochloride

R-33 : 3-acetamido-N-[3-(trifluoromethoxy)phenyl]-D-alaninamide

R-34 : 3 - [(methanesulfonyl)amino] -N- [3 -(trifluoromethoxy)phenyl] -D-alaninamide

R-35: N-phenyl-D-serinamide— hydrochloride

R-36: N-[3-(trifluoromethoxy)phenyl]-D-lysinamide

R-37 : N ⁶ -acetyl-N- [3 -(trifluoromethoxy)phenyl] -D-ly sinamide

R-38 : N ⁶ -(methanesulfonyl)-N- [3 -(trifluoromethoxy)phenyl] -D-ly sinamide

R-39 : 2-amino-2-( 1 , 1 -dioxo- 1 lambda ⁶ -thian-4-yl)-N- [3 -(trifluoromethoxy)phenyl] acetamide-

- hydrochloride

R-40: l-[(3-oxidanylideneseryl)amino]-3-(trifluoromethoxy)benzene� �� hydrochloride R-41 : N-(5-nitropyridin-2-yl)glycinamide~ 2 hydrochloride

R-42: 2-amino-2-(pyridin-3-yl)-N-[3-(trifluoromethoxy)phenyl]aceta mide~ 2 hydrochloride

R-43: N-[3-(propan-2-yl)phenyl]-D-serinamide—trifluoroacetate

R-44: 3-(l ,3-thiazol-2-yl)-N-[3-(trifluoromethoxy)phenyl]alaninamide~ hydrochloride R-45: N-[4-(trifluoromethoxy)phenyl]-D-serinamide—trifluoroaceta te

R-46: (2R)-2-amino-4,4,4-trifluoro-N-[3-(trifluoromethoxy)phenyl]b utanamide

R-47 : 3 -thiophen-2-yl-N- [3 -(trifluoromethoxy)phenyl] alaninamide

R-48: N-(3-ethoxyphenyl)-D-serinamide—trifluoroacetate

R-49: N-{3-[(propan-2-yl)oxy]phenyl}-D-serinamide—trifluoroaceta te

R-50: N-(l-phenyl-lH-pyrazol-3-yl)-D-serinamide—trifluoroacetate

R-51 : N-[3-(benzyloxy)phenyl]-D-serinamide—trifluoroacetate

R-52: N-[3-(2-phenylethoxy)phenyl]-D-serinamide—trifluoroacetate R-53: N-[3-(hexyloxy)phenyl]-D-serinamide— trifluoroacetate

R-54: 3-(2-oxo- 1 ,2-dihydroquinolin-4-yl)-N-[3-(trifluoromethoxy)phenyl]alani namide~ hydrochloride

R-55: N-(2,3-dihydro-l H-inden-1 -yl)-D-serinamide— hydrochloride

R-56: N-[3-(phenylethynyl)phenyl]-D-serinamide— hydrochloride

R-57: (2R)-6-oxo-N-[3-(trifluoromethoxy)phenyl]piperazine-2-carbox amide

R-58: N-{[3-(aminomethyl)phenyl]methyl}-D-serinamide— 2 hydrochloride .

R-59: N-{[4-(aminomethyl)phenyl]methyl}-D-serinamide~ 2 hydrochloride

R-60: N-[(3-bromophenyl)methyl]-D-serinamide— hydrochloride

R-61 : N-[(2-bromophenyl)methyl]-D-serinamide~ hydrochloride

R-62 : (2R)-2-amino-3 -hydroxy- 1 - [4-(2-phenylethyl)piperidin- 1 -yljpropan- 1 -one— hydrochloride

R-63 : N- { [2-(trifluoromethoxy)phenyl]methyl} -D-serinamide~ hydrochloride

R-64: 3-(l -benzofuran-2-yl)-N-[3-(trifluoromethoxy)phenyl]-D-alaninarn ide

R-65: N-l,3-benzothiazol-6-yl-D-serinamide~ hydrochloride

R-66: N-(5-phenyl-lH-pyrazol-3-yl)-D-serinamide~ hydrochloride

R-67: N-{[3-(trifluoromethoxy)phenyl]methyl}-D-serinamide~ hydrochloride

R-68 : N- { [4-(trifluoromethoxy)phenyl]methyl } -D-serinamide— hydrochloride

R-69: (2R)-2-amino-3 -hydroxy- 1 -[7-(tfifluoromethyl)-3,4-dihydroisoquinolin-2(l H)- yljpropan- 1 -one— hydrochloride

R-70 : N- {2- [3 -(trifluoromethoxy)phenyl] ethyl } -D-serinamide~ hydrochloride

R-71 : N-{2-[4-(trifluoromethoxy)phenyl]ethyl} -D-serinamide— hydrochloride

R-72 : N- 1 H-indol-5-yl-D-serinamide

R-73: N-(4-phenylpyrrolidin-3-yl)-D-serinamide~ 2 hydrochloride

R-74: N- [(3 -sulfamoylphenyl)methyl] -D-serinamide— hydrochloride

R-75: N-[(4-sulfamoylphenyl)methyl] -D-serinamide— hydrochloride

R-76: N-[(4'-amino[l,r-biphenyl]-4-yl)methyl]-D-serinamide— 2 hydrochloride

R-77: N-{[6-(2,2,2-trifluoroethoxy)pyridin-3-yl]methyl}-D-serinami de— 2 hydrochloride R-78: N-[2-(benzylamino)ethyl]-D-serinamide— 2 hydrochloride

R-79: N-{[2-(2,2,2-trifluoroethoxy)pyridin-3-yl]methyl}-D-serinami de— 2 hydrochloride R-80: N-[2-hydroxy-2-(3-phenoxyphenyl)ethyl]-D-serinamide— hydrochloride

R-81 : S-[3-(trifluoromethoxy)phenyl] (2R)-2-amino-3-hydroxypropanethioate— hydrochloride

R-82: N-(5-bromopyridin-3-yl)-D-serinamide

R-83: N-(3-bromo-2-methylphenyl)-D-serinamide

R-84 : 3 - [(2,2-difluoroethyl)amino] -N- [3 -(trifluoromethoxy)phenyl] -D-alaninamide R-85: (2R)-2-amino-l -[4-(4-fluorobenzoyl)piperazin-l-yl]-3-hydroxypropan-l-one� � hydrochloride

R-86: N-(2-methyl-lH-indol-5-yl)-D-serinamide

R-87: N-(3-benzylphenyl)-D-serinamide

R-88 : 1 -[(4-tert-butylphenyl)methyl]-4-D-serylpiperazin-2-one~ hydrochloride

R-89 : (2R)-2-amino- 1 - { 4-[(4-fluorophenyl)methyl]piperazin- 1 -yl } -3 -hydroxypropan- 1 -one— 2 hydrochloride

R-90: (2R)-2-amino- 1 - {4-[(4-bromophenyl)methyl]piperazin- 1 -yl} -3-hydroxypropan- 1 -one— 2 hydrochloride

R-91 : (2R)-2-amino-3 -hydroxy- 1 - {4- [(2-methylphenyl)methyl]piperidin- 1 -yl } propan- 1 -one— hydrochloride

R-92 : (2R)-2-amino-3 -hydroxy- 1 - {4-[(3-methylphenyl)methyl]piperidin- 1 -yl } propan- 1 -one— hydrochloride

R-93 : (2R)-2-amino-3 -hydroxy- 1 -(4-phenoxypiperidin- 1 -yl)propan- 1 -one— hydrochloride R-94: (2R)-2-amino-3 -hydroxy- 1 -(1 'H,2H,4H-spiro[ 1 -benzopyran-3,4'-piperidin]- 1 '- yl)propan-l -one— hydrochloride

R-95 : (2R)-2-amino- 1 -[3-(4-benzylphenoxy)pyrrolidin- 1 -yl]-3-hydroxypropan- 1 -one~ hydrochloride

R-96 : (2R)-2-amino-3 -hydroxy- 1 -(3 -phenoxyazetidin- 1 -yl)propan- 1 -one— hydrochloride R-97: N-(2-phenyl-lH-imidazol-4-yl)-D-serinamide

R-98 : 3-( 1 , 1 -dioxo- 1 lambda ⁶ ,4-thiazinan-4-yl)-N- [3 -(trifluoromethoxy)phenyl]-D- alaninamide

R-99: 3- { [2-(methanesulfonyl)ethyl]amino} -N-[3-(trifluoromethoxy)phenyl]-D-alaninamide R- 100: 3 -amino- 1 , 1 -dioxo-N- [3 -(trifluoromethoxy)phenyl] - 1 lambda ⁶ -thiolane-3 - carboxamide— hydrochloride

R-101 : S-methyl-N-[3-(trifluoromethoxy)phenyl]-D-cysteinamide

R- 102 : 3 -(methanesulfony 1)-N- [3 -(trifluoromethoxy)phenyl] -D-alaninamide

R- 103 : N- { 1 -[(4-chlorophenyl)methyl] - 1 H-pyrazol-3 -yl } -D-serinamide

R-l 04: 3-hydroxy-N-[3-(trifluoromethoxy)phenyl]-alpha-asparagine

R-105: (2R)-2-amino-3 -hydroxy- l-(4-phenylpiperazin-l-yl)propan-l -one— 2 hydrochloride R- 106: (2R)-2-amino-3 -hydroxy- 1 -(4-phenyl-3,6-dihydropyridin- 1 (2H)-yl)propan- 1 -one— hydrochloride

R- 107 : (2R)-2-amino- 1 -( 1 ,3 -dihydro-2H-isoindol-2-yl)-3 -hydroxypropan- 1 -one—

hydrochloride

R- 108 : (2R)-2-amino-3 -hydroxy- 1 -(4-phenylpiperidin- 1 -yl)propan- 1 -one— hydrochloride R- 109 : (2R)-2-amino-3 -hydroxy- 1 - [(3 S)-3 -phenylpyrrolidin- 1 -yljpropan- 1 -one—

hydrochloride

R-l 10: (2R)-2-amino-3-hydroxy-l -[(3R)-3-phenylpyrrolidin-l -yljpropan- 1 -one— hydrochloride

R-111 : (2R)-2-amino-3-hydroxy-l-(l ,2,4,5-tetrahydro-3H-3-benzazepin-3-yl)propan-l-one— hydrochloride

R-112: (2R)-2-amino-3 -hydroxy- 1 -(3 -phenylazetidin-l-yl)propan-l -one— hydrochloride R- 1 13 : (2R)-2-amino-3 -hydroxy- 1 - [4-(4-methylbenzene- 1 -sulfonyl)piperidin- 1 -yljpropan- 1 - one— hydrochloride

R- 1 14 : N- 1 H-pyrrolo [3 ,2-b]pyridin-3 -yl-D-serinamide

R-115: N-lH-indol-3-yl-3-(l,3-thiazol-4-yl)-D-alaninamide~ hydrochloride

R-116: (2R)-2-amino-l-(4-benzylpiperidin-l-yl)-3 -hydroxypropan- 1 -one— hydrochloride R-117: N-{3 - [(naphthalen-2-yl)methoxy]phenyl } -D-serinamide

R-118: N-(2-hydroxyethyl)-N-[3-(propan-2-yl)phenyl]glycinamide

R-119: (2R)-2-amino-3-hydroxy-l-[(3S)-3-phenylpiperidin-l-yl]propan -l-one formate R- 120 : formic acid— (2R)-2-amino-3 -hydroxy- 1 - [(3R)-3 -phenylpiperidin- 1 -yl]propan- 1 -one formate

R-121 : N-{3-[([l,l'-biphenyl]-4-yl)methoxy]phenyl}-D-serinamide

R-122: glycyl-N-[3-(propan-2-yl)phenyl]glycine~ hydrochloride

R-123 : N-( 1 -benzyl- 1 H-pyrazol-3-yl)-D-serinamide

R- 124 : ethyl 3 -hydroxy-N- [3 -(trifluoromethoxy)phenyl] -alpha-asparaginate

R-125: N-methyl-N-(3-phenoxypropyl)-D-serinamide— hydrochloride

R- 126 : N-methyl-N-(4-phenylbutyl)-D-serinamide~ hydrochloride

R- 127: 2-amino- 1 - { 4- [(4-methylphenyl)methyl]piperidin- 1 -yl } ethan- 1 -one

R-128: (2R)-2-amino- 1 -(4-benzyl-3,6-dihydropyridin- 1 (2H)-yl)-3 -hydroxypropan- 1 -one R-129: (2R)-2-amino-3-(4-benzylpiperidin-l-yl)-3-oxopropyl D-serinate-- 2 hydrochloride R-130: (2R)-2-amino-2-(l,l-dioxo-llambda ⁶ -thietan-3-yl)-N-[3- (trifluoromethoxy)phenyl]acetamide~ hydrochloride

R- 131 : N- 1 H-indol-3-yl-D-methioninamide

R- 132 : (3R)-3-amino- 1 -([ 1 , 1 '-biphenyl]-4-yl)piperidin-2-one~ hydrochloride

R- 133 : (2R)-2-amino-3 -hydroxy- 1 -(4-{ [3-(phenylethynyl)phenyl]methyl}piperidin- 1 - yl)propan-l-one— hydrochloride

R- 134 : (2R)-2-amino- 1 - {4- [([ 1 , 1 -biphenyl] -3 -yl)methyl]piperidin- 1 -yl } -3 -hydroxypropan- 1 - one— hydrochloride

R- 135 : (2R)-2-amino- 1 -(4-benzyl-4-hydroxypiperidin- 1 -yl)-3-hydroxypropan- 1 -one

R- 136 : (2R)-2-amino-3 -hydroxy- 1 - { 4- [hydroxy(phenyl)methyl]piperidin- 1 -yl } propan- 1 -one R- 137: (2R)-2-amino- 1 -( 1 ,3-dihydro- 1 Ή-spiro [indene-2,4'-piperidin]- 1 '-yl)-3- hydroxypropan- 1 -one

R- 138 : (2R)-2-amino-3 -hydroxy- 1 - [4-(4-methylbenzoyl)piperidin- 1 -yljpropan- 1 -one

R-139: (2R)-2-amino-3-hydroxy-l -(4-{[3-(2-phenylethyl)phenyl]methyl}piperidin-l- yl)propan-l -one— hydrochloride

R-140: N-tl '-biphenylJ-S-yl-D-serinamide

R- 141 : (2R)-2-amino-3-hydroxy- 1 - {4-[(4-methylphenyl)methyl]-3 ,6-dihydropyridin- 1 (2H)- yl}propan-l-one

R- 142 : (2R)-2-amino- 1 -(7-bromo-3 ,4-dihydroisoquinolin-2( 1 H)-yl)-3 -hydroxypropan- 1 -one- - hydrochloride

R- 143 : 2-amino-6- [(naphthalen-2-yl)methoxy] -3 ,4-dihydronaphthalen- 1 (2H)-one— hydrochloride

R-144: (3S)-3-amino-l-[3-(trifluoromethoxy)phenyl]pyrrolidin-2-one~ hydrochloride R- 145 : (3R)-3-amino- 1 -[3-(trifluoromethoxy)phenyl]pyrrolidin-2-one— hydrochloride R-146: (2R)-2-amino-N-(lH-indol-3-yl)-4-(methanesulfonyl)butanamide ~ hydrochloride R-147: (3R)-3-amino-l -[3-(benzyloxy)phenyl]pyrrolidin-2-one~ hydrochloride

R-148: (3R)-3-amino-l-{3-[(4-methylphenoxy)methyl]phenyl}pyrrolidin -2-one—

hydrochloride

R-l 49: (2R)-2-amino- 1 -(5-bromo-2,3 -dihydro- 1 H-indol- 1 -yl)-3-hydroxypropan- 1 -one R-l 50: N-[(4-bromophenyl)methyl]-N-methyl-D-serinamide~ hydrochloride

R-151 : N-(4-phenylbutyl)-D-serinamide~ hydrochloride

R-l 52: 3-amino-l-(6-bromopyridin-2-yl)pyrrolidin-2-one~ hydrochloride

R- 153 : (3R)-3-amino- 1 -(6-iodopyridin-2-yl)piperidin-2-one— hydrochloride

R-154: formic acid~(2R)-2-amino-3-hydroxy-l-(4-phenoxy-2,3-dihydro-lH-indo l-l- yl)propan-l-one (1/1)

R- 155: 3-amino- 1 -([ 1 , 1 '-biphenyl]-3-yl)pyrrolidin-2-one

R- 156: 3-amino-l -[3-(phenylethynyl)phenyl]pyrrolidin-2-one— hydrochloride

R- 157: (2R)-2-amino-l -(2,3-dihydro-l H-pyrrolo[2,3-b]pyridin- 1 -yl)-3 -hydroxypropan- 1 -one R- 158 : (2R)-2-amino- 1 -(2,3-dihydro- 1 H-pyrrolo [3 ,2-c]pyridin- 1 -yl)-3 -hydroxypropan- 1 -one R- 159: (2R)-2-amino- 1 -(2,3-dihydro- 1 H-pyrrolo[3 ,2-b]pyridin- 1 -yl)-3 -hydroxypropan- 1 -one R- 160: (2R)-2-amino-3 -hydroxy- 1 -(2-phenyl-2,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridin- 5-yl)propan-l-one~ hydrochloride

R-l 61 : N-l H-pyrrolo [2,3 -b]pyridin-3-yl-D-serinamide

R-162: (2R)-2-amino-3-hydroxy-l-(l-phenyl-l ,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridin- 5 -yl)propan- 1 -one

R-163: (2R)-2-amino-3-hydroxy-l-(6-hydroxy-2,3-dihydro-lH-indol-l-y l)propan-l-one R- 164: (2R)-2-amino-3 -hydroxy-2-methyl- 1 - { 4- [(4-methylphenyl)methyl]piperidin- 1 - yl}propan-l-one

R-l 65: 2-methyl-N-[3-(propan-2-yl)phenyl]-D-serinamide

R- 166 : 3 -amino-2-hydroxy- 1 - { 4- [(4-methylpheny l)methyl]piperidin- 1 -yl } propan- 1 -one R-l 67: (2 R)-2-amino-3 -hydroxy- 1 -(2 -methyl -2, 3 -dihydro- 1 H-indol- 1 -yl)propan-l -one R- 168 : (2R)-2-amino-3-hydroxy- 1 -(spiro [cyclobutane- 1 ,3 -indol]- 1 '(2'H)-yl)propan- 1 -one R- 169: (2R)-2-amino- 1 -[3-(2-aminoethyl)-2,3-dihydro- 1 H-indol-1 -yl]-3 -hydroxypropan- 1 - one

R-170: N-lH-pyrrolo[3,2-c]pyridin-3-yl-D-serinamide

R-171 : 3-amino-l-[([l,r-biphenyl]-4-yl)methyl]pyrrolidin-2-one

R- 172: (2R)-2-amino-3-hydroxy- 1 -( 1 Ή-spiro [cyclopropane- 1 ,4'-isoquinolin]-2'(3 Ή)- yl)propan-l -one— hydrochloride

R-173: N-lH-pyrrolo[2,3-b]pyridin-5-yl-D-alpha-asparagine

R- 174: (2R)-2-amino- 1 -(5-bromo- 1 ,3-dihydro-2H-isoindol-2-yl)-3-hydroxypropan- 1 -one R- 175 : (2R)-2-amino- 1 -(4-bromo- 1 ,3 -dihydro-2H-isoindol-2-yl)-3 -hydroxypropan- 1 -one R- 176 : 5 - { [2-(4-chlorophenyl)ethyl] sulfanyl } - 1 H-imidazole

R- 177 : (4- { [2-(4-chlorophenyl)ethyl] sulfanyl } pyridin-2-yl)methanol

R-178: N-({4-[(2-phenylethyl)sulfanyl]pyridin-2-yl}methyl)methanesu lfonamide

R-l 79: methyl 4-{ [2-([l , 1 '-biphenyl]-4-yl)ethyl]sulfanyl}pyridine-2-carboxylate

R-180: 4-{[2-([l,l'-biphenyl]-4-yl)ethyl]sulfanyl}pyridine-2-carbox ylic acid

R-181 : l-(lH-imidazol-l-yl)-3-phenoxypropan-2-one

R- 182 : N-(4-chlorophenyl)-3 -( 1 H-imidazol- 1 -yl)propanamide

R- 183 : 1 -[2-(4-chlorophenoxy)ethyl]- 1 H-imidazol-2-amine

R- 184: 1 -[3-(4-chlorophenoxy)-2-methoxypropyl]- 1 H-imidazole

R-l 85: l-(4-chlorophenoxy)-3-(l H-imidazol- l-yl)propan-2-amine

R- 186: 1 -[2-(4-chlorophenoxy)ethyl]-4-nitro- 1 H-imidazole

R-l 87: l-[4-(4-chlorophenyl)butyl]-l H-imidazole

R- 188 : 1 - [2-(4-chlorophenoxy)ethyl] - 1 H-tetrazole

R-l 89: 2-[2-(4-chlorophenoxy)ethyl]-2H-tetrazole

R-190: l-[4-(4-chlorophenyl)butyl]-lH-imidazol-2-amine

R-191 : l-[3-(4-chlorophenyl)propyl]-4-nitro-l H-imidazole

R- 192 : 1 - [3 -(4-chlorophenyl)propyl] - 1 H-imidazol-2 -amine

R- 193 : 1 - [3 -(4-chlorophenyl)propyl] - 1 H-imidazole-2-carboxylic acid

R-l 94: ethyl l-[3-(4-chlorophenyl)propyl]-lH-imidazole-2-carboxylate

R-195: ethyl l-[4-(4-chlorophenyl)butyl]-lH-imidazole-2-carboxylate

R- 196 : 1 - [4-(4-chlorophenyl)butyl] - 1 H-imidazole-2-carboxylic acid

R- 197: 1 -[3-(4-chlorophenyl)propyl]- 1 H-imidazole-2-carboxamide

R-l 98: l-[3-(4-chlorophenyl)propyl]-N-methyl-lH-imidazole-2-carboxa mide

R- 199 : 4-bromo- 1 - [3 -(4-chlorophenyl)propyl] - 1 H-imidazole

R-200: 5-bromo- l-[3-(4-chlorophenyl)propyl]-l H-imidazole

R-201 : 1 - [3 -(4-chlorophenyl)propyl] -4-methyl- 1 H-imidazole

R-202 : methyl 1 - [3 -(4-chlorophenyl)propyl] - 1 H-imidazole-5 -carboxylate R-203: methyl l-[3-(4-chlorophenyl)propyl]-lH-imidazole-4-carboxylate R-204 : 1 - [3 -(4-chlorophenyl)propyl] - 1 H-imidazole-4-carboxylic acid

R-205 : 1 -[3-(4-chlorophenyl)propyl]- 1 H-imidazole-5-carboxylic acid

R-206: 3-{[3-(4-chlorophenyl)propyl]sulfanyl}-4H-l ,2,4-triazole

R-207: l-[3-(4-chlorophenyl)propyl]-lH-imidazol-4-amine~ hydrochloride

R-208: l-[3-(4-chlorophenyl)propyl]-5-methyl-lH-imidazole

R-209: 2-[3-(4-chlorophenyl)propyl]-4-methyl-2,4-dihydro-3H-l,2,4-t riazole-3-thione R-210: l-[3-(4-chlorophenyl)propyl]-lH-imidazol-5-amine~ hydrochloride

R-21 1 : N-({ l-[3-(4-chlorophenyl)propyl]-lH-imidazol-2-yl}methyl)-2- (methanesulfonyl)ethan-l -amine

R-212: 4- { [2-(4-chlorophenyl)ethyl] sulfanyl }pyridine-2-carboxylic acid

R-213: 4-{[2-(4-chlorophenyl)ethyl]sulfanyl}pyridine

R-214: N- { 1 -[2-(4-chlorophenoxy)ethyl]- 1 H-imidazol-2-yl } acetamide

R-215: l-[3-(4-chlorophenyl)propyl]-4-fluoro-lH-imidazole

R-216: 3-hydroxy-5-[(E)-2-phenylethenyl]pyridin-2(lH)-one

R-217: 3-hydroxy-5-[(2-phenylethyl)sulfanyl]pyridin-2(lH)-one

R-218 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } -3 -hydro xypyridin-2( 1 H)-one

R-219: 3-hydroxy-5-[(2-phenoxyethyl)sulfanyl]pyridin-2( 1 H)-one

R-220: 5-[(2-phenylethyl)sulfanyl]pyridin-2(l H)-one

R-221 : 5-{[2-([l,l'-biphenyl]-4-yl)ethyl]sulfanyl}-3-methoxypyridin -2(lH)-one

R-222 : 5- { [2-([ 1 , 1 '-biphenyl] -4-yl)ethyl] sulfanyl } -3 -hydroxypyridin-2( 1 H)-one

R-223 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } -2-methoxypyridine

R-224 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } -2-ethoxy-3 -methoxypyridine

R-225 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } -3 -methoxypyridin-2( 1 H)-one

R-226: 5-{[2-(4-chlorophenyl)ethyl]sulfanyl}pyridin-2(lH)-one

R-227 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } -3 -methoxypyrazin-2( 1 H)-one

R-228: 5-[(3-fluorophenyl)sulfanyl]-3-hydroxypyridin-2(lH)-one

R-229 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } - 1 ,4-dihydropyrazine-2,3 -dione

R-230 : 5 - [(3-chloro-5 -fluorophenyl)sulfanyl]-3 -hydroxypyridin-2( 1 H)-one

R-231 : 4-{[2-(4-chlorophenyl)ethyl]sulfanyl}thieno[2,3-c]pyridin-7( 6H)-one

R-232 : 5 - { [2-(4-chlorophenyl)ethyl] sulfanyl } -3 -fluoropyridin-2( 1 H)-one

R-233 : 4- { [2-(4-chlorophenyl)ethyl] sulfanyl } -7-methoxy- 1 H-pyrrolo [2,3 -c]pyridine R-234: 3-chloro-5-{[2-(4-chlorophenyl)ethyl]sulfanyl}pyridin-2(lH)- one

R-235 : 4- { [2-(4-chlorophenyl)ethyl] sulfanyl } - 1 ,6-dihydro-7H-pyrrolo [2,3 -c]pyridin-7-one R-236 : 5 - [(3 -fluoro-5-propoxyphenyl)sulfanyl] -3 -hydroxypyridin-2( 1 H)-one

R-237 : 5- { [2-(3 -chloropheny l)ethyl] sulfanyl } -3 -hydroxypyridin-2( 1 H)-one

R-238: 5-[(4-chlorophenyl)sulfanyl]-3-hydroxypyridin-2( 1 H)-one R-239 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } -2-oxo- 1 ,2-dihydropyridine-3 -carboxylic acid R-240 : 5- { [2-(4-chlorophenyl)ethyl] sulfanyl } -3 -(hydroxymethyl)pyridin-2( 1 H)-one

R-241 : 3-hydroxy-5-[(4-hydroxyphenyl)sulfanyl]pyridin-2(lH)-one

R-242 : 5- { [3 -(4-chlorophenyl)propyl]sulfanyl } -3 -hydroxypyridin-2( 1 H)-one

R-243: 5-({2-[4-(benzyloxy)phenyl]ethyl}sulfanyl)-3-hydroxypyridin- 2(lH)-one

R-244: 5-[2-(4-chlorophenyl)ethanesulfonyl]-3-hydroxypyridin-2(l H)-one

R-245: 3-hydroxy-5-{[2-(4-hydroxyphenyl)ethyl]sulfanyl}pyridin-2(lH )-one

R-246 : 3-hydroxy-5-( { 3 - [4-(phenylethynyl)phenyl]propyl } sulfanyl)pyridin-2( 1 H)-one R-247 : 5 - { [3 - ( [ 1 , l'-biphenyl] -4-yl)propyl] sulfanyl } -3 -hydroxypyridin-2( 1 H)-one

R-248: 3-hydroxy-5-({2-[4-(phenylethynyl)phenyl]ethyl}sulfanyl)pyri din-2(lH)-one R-249: 3-hydroxy-5-({3-[4-(2-phenylethyl)phenyl]propyl} sulfanyl)pyridin-2(l H)-one R-250: 3-hydroxy-5-{ [5-(pyridin-4-yl)-4H-l ,2,4-triazol-3-yl]sulfanyl}pyridin-2(lH)-one R-251 : 3-hydroxy-5-[(4-{ [4-(3-hydroxypropyl)phenyl]ethynyl}phenyl)sulfanyl]pyridin- 2(lH)-one

R-252: 5-{[2-(4-chlorophenyl)ethyl]sulfanyl}-4-fluoro-3-hydroxypyri din-2(lH)-one

R-253 : 3-hydroxy-5-({2-[4*-(3-hydroxypropoxy)[ 1 , 1 '-biphenyl] -4-yl] ethyl} sulfanyl)-l -(3- hydroxypropyl)pyridin-2( 1 H)-one

R-254 : 6- { [2-(4-chlorophenyl)ethyl] sulfanyl } -4-hydroxypyridazin-3 (2H)-one

R-255: ^* 3-hydroxy-4-[(3-phenylpropyl)amino]pyridin-2(lH)-one

R-256 : 5- { [3 -(4-chlorophenyl)- 1 H-1 ,2,4-triazol- 1 -yljmethyl } -3 -hydroxypyridin-2( 1 H)-one R-257: [4-(4-chlorophenyl)butyl]propanedioic acid

R-258 : 2-(4-chlorophenyl)-5 - { [(4H- 1 ,2,4-triazol-3 -yl)sulfanyl]methyl } - 1 ,3 ,4-oxadiazole R-259: 2-(lH-pyrrol-l-yl)benzoic acid

R-260: (3-ethyl-l,2,4-oxadiazol-5-yl)methyl carbamimidothioate— hydrochloride

R-261 : 5-{[4-(4-chlorophenyl)-l,2,3-triazol-l-yl]methyl}-3-hydroxy- lH-pyridin-2-one R-262 : (E)-5-(3 -(4-chlorophenyl)prop- 1 -en- 1 -yl)-3 -hydroxypyridin-2( 1 H)-one

R-263 : (E)-5-(2-(4-chlorophenyl)prop- 1 -en- 1 -yl)-3-hydroxypyridin-2(l H)-one

Examples

Synthesis of Compound-1

2- Amino-3 -hydroxy- 1 - {4- [(4- { [4-(hydroxymethyl)phenyl]ethynyl } phenyl)methyl]piperidin- 1 -yl } -4-(methanesulfonyl)butan- 1 -one

Step 1)

To a stirred solution of diisopropylamine (4.7 mL) in THF (0.21 L) was added 1.6 mol/L n- butyllithium in hexane (20 mL) at -78 °C. The mixture was allowed to warm to 0 °C, stirred for 30 minutes, then cooled to -78 °C and ethyl 2-(dibenzylamino)acetate (6 g) in THF was added into the mixture. After stirring for 30 minutes, 2-methylsulfanylacetaldehyde (2.3 g) in THF was added into the resulting mixture. The reaction mixture was allowed to warm to room temperature, stirred further 3 hours, quenched with a saturated aqueous sodium bicarbonate and extracted with CHC1 ₃ three times. The organic layer was passed through a phase separator and concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with OH-type silica gel column chromatography (8-31 % EtOAc in n-hexane) to give the title compound (1.2 g, 15 % yield) as a yellow oil.

MS (ESI) m/z : 374 [M+l] ⁺ .

RT = 0.981 min.

LCMS condition : C.

Step 2)

Ethyl 2-(dibenzylamino)-3-hydroxy-4-(methylsulfonyl)butanoate

To a stirred solution of ethyl 2-(dibenzylamino)-3-hydroxy-4-methylsulfanyl-butanoate (1.2 g) in CHC1 ₃ (10 mL) was added m-chloroperbenzoic acid (2.0 g) at 0 °C. The reaction mixture was stirred at room temperature overnight, quenched with a saturated aqueous sodium thiosulfate and extracted with CHCI3 twice. The organic layer was passed through a phase separator and concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with OH-type silica gel column chromatography (8-100 % EtOAc in n-hexane) to give the title compound (0.58 g, 47 % yield) as colorless powder.

MS (ESI) m/z : 406 [M+l] ⁺ .

RT = 0.847 min.

LCMS condition : C. -amino-3-hydroxy-4-(methylsulfonyl)butanoate

To a solution of ethyl 2-(dibenzylamino)-3-hydroxy-4-methylsulfonyl-butanoate (0.40 g) in EtOH (9.9 mL) was added palladium hydroxide on carbon (50 mg). The mixture was stirred at room temperature overnight under hydrogen atmosphere. The reaction mixture was filtered and filtrate was concentrated in vacuo to give the title compound (0.24 g, quant.) as a crude oil, which was used in the next step without further purification.

MS (ESI) m/z : 226 [M+l] ⁺ .

RT = 0.258 min.

LCMS condition : B.

Step 4)

Ethyl 2-((tert-butoxycarbonyl)amino)-3-hydroxy-4-(methylsulfonyl)b utanoate

To a stirred solution of ethyl 2-amino-3-hydroxy-4-methylsulfonyl-butanoate (0.17 g as crude material) in THF (3.8 mL) and EtOH (L5 mL) were added (Boc) ₂ 0 (0.20 g) and potassium carbonate (0.27 g). After stirring for 3 hours at room temperature, the reaction mixture was quenched with water and extracted with CHC1 ₃ three times. The organic layer was concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with OH-type silica gel column chromatography (30-100 % EtOAc in n-hexane) to give the title compound (0.27 g, quant.) as a colorless oil.

MS (ESI) m/z : 348 [M+23] ⁺ .

RT = 0.635 min.

LCMS condition : B.

Step 5)

Sodium 2-((tert-butoxycarbonyl)amino)-3-hydroxy-4-(methylsulfonyl)b utanoate

To a solution of ethyl 2-(tert-butoxycarbonylamino)-3-hydroxy-4-methylsulfonyl-buta noate (0.28 g) in EtOH (2.9 mL) was added 10 mol/L aqueous sodium hydroxide (0.26 mL). After stirring for 3 hours at room temperature, the resulting precipitates were filtered and collected to give the title compound (0.20 g, 73 % yield) as a colorless solid.

MS (ESI) m/z : 296 [M-l]-.

RT = 0.879 min.

LCMS condition : A.

Step 6)

xylate

A mixture of tert-butyl 4-((4-(trifluoromethylsulfonyloxy)phenyl)methyl)piperidine-l - carboxylate (0.37 g), (4-(hydroxymethyl)phenyl)acetylene (0.37 mL), Cul (17 mg), PdCl ₂ (PPh ₃ ) ₂ (61 mg) and TEA (5 mL) in DMF (5 mL) was stirred at 70 °C for 15 hours. After cooling the mixture to room temperature, the insoluble matter was removed by filtration through Celite® and washed with EtOAc. The filtrate was concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (EtOAc in n- hexane) to give the title compound (0.14 g, 40 % yield) as a pale orange solid.

MS (ESI) m/z : 428 [M+23] ⁺ .

RT = 1.024 min.

LCMS condition : C.

Step 7)

loride

To a solution of tert-butyl 4-(4-((4-(hydroxymethyl)phenyl)ethynyl)benzyl)piperidine-l- carboxylate (0.14 g) in 1,4-dioxane (4 mL) was added 4 mol/L HC1 in 1 ,4-dioxane (8 mL) at room temperature. The reaction mixture was stirred at the same temperature for 4 hours and concentrated in vacuo to give the title compound (0.13 g, quant.) as a pale yellow solid. MS (ESI) nVz : 306 [M+l] ⁺ .

RT = 0.543 min.

LCMS condition : B.

Step 8)

Tert-butyl (3 -hydroxy- 1 -(4-(4-((4-(hydroxymethyl)phenyl)ethynyl)benzyl)piperid

(methylsulfonyl)- 1 -oxobutan-2-yl)carbamate

To a stirred solution of [4-[2-[4-(4-piperidylmethyl)phenyl]ethynyl]phenyl]methanol hydrochloride (34 mg) in DMF (2.0 mL) were added sodium 2-(tert-butoxycarbonylamino)- 3-hydroxy-4-methylsulfonyl-butanoate (35 mg), HATU (57 mg) and DIPEA (52 μΐ). The mixture was stirred for 3 hours at room temperature. The reaction mixture was purified with prep-HPLC to give the title compound (56 mg, 96 % yield) as an amorphous.

MS (ESI) m/z : 607 [M+23] ⁺ .

RT = 0.786 min.

LCMS condition : C.

Step 9)

2- Amino-3 -hydroxy- 1 - { 4- [(4- { [4-(hydroxymethyl)phenyl] ethynyl } phenyl)methyl]piperidin- 1 -yl } -4-(methanesulfonyl)butan- 1 -one (Compound- 1 )

A solution of tert-butyl N-[2-hydroxy-l-[4-[[4-[2-[4-

(hydroxymethyl)phenyl]ethynyl]phenyl]methyl]piperidine-l- carbonyl]-3-methylsulfonyl- propyljcarbamate (53 mg) in formic acid (1.5 mL) was stirred for 2 hours at room

temperature. The reaction mixture was diluted with CHCb and concentrated in vacuo. To the residue was added 7 mol/L ammonia in MeOH (2 mL) and the resulting mixture was stirred for 10 minutes at room temperature. The reaction mixture was concentrated in vacuo and purified with prep-HPLC to give the title compound (Compound-1 , 1 1 mg, 35 % yield) as a colorless powder.

Ή-NMR, MS and LCMS retention time data of Compound-1 are shown in Table 2.

Synthesis of Compound-16 (2R)-2-amino-3-hydroxy-l-(4-{2-[4-(2-hydroxyethoxy)phenyl]et hyl}-2,3-dihydro-lH-indol- l-yl)propan-l-one - hydrochloride

Step 1)

Tert-butyl 4-((4-(2-((tetrahydro-2H-pyran-2-yl)oxy)ethoxy)phenyl)ethyny l)indoline- 1 - carboxylate

A solution of tert-butyl 4-bromoindoline-l -carboxylate (0.50 g),

bis(triphenylphosphine)palladium(II) dichloride (0.24 g), copper iodide (64 mg),

triphenylphosphine (0.18 g), hexamethyldisilazane (0.52 mL) and triethylamine (1.7 g) in DMF (8.4 mL) was evacuated and backfilled with nitrogen three times. The mixture was stirred for 10 minutes at 1 10 °C. 2-[2-(4-Ethynylphenoxy)ethoxy]tetrahydropyran (0.83 g). was added into the mixture. The reaction mixture was stirred for 5 hours at 110 °C and overnight at room temperature, quenched with water and extracted with EtOAc. The organic layer was washed with water twice, dried over MgS0 ₄ , filtered and concentrated in vacuo. The residue was charged onto ISOLUTE® HM-N and purified with OH-type silica gel column chromatography (3-100 % EtOAc in n-hexane) to give the title compound (0.57 g, 73 % yield) as a colorless solid.

Ή NMR (600 MHz, CHLOROFORM-d) δ ppm 1.50 - 1.67 (m, 13 H), 1.71 - 1.79 (m, 1 H), 1.81 - 1.89 (m, 1 H), 3.18 - 3.25 (m, 2 H), 3.51 - 3.57 (m, 1 H), 3.80 - 3.86 (m, 1 H), 3.87 - 3.93 (m, 1 H), 3.96 - 4.10 (m, 3 H), 4.13 - 4.23 (m, 2 H), 4.68 - 4.74 (m, 1 H), 6.89 - 6.94 (m, 2 H), 7.05 - 7.17 (m, 2 H), 7.26 - 7.27 (m, 1 H), 7.40 - 7.48 (m, 2 H).

Step 2)

2-(4-(Indolin-4-ylethynyl)phenoxy)ethanol hydrochloride

The title compound was obtained in the manner as with the "Synthesis of Compound- 1 : step- 7" using the corresponding materials.

MS (ESi) m/z : 280 [M+l] ⁺ .

RT = 0.635 min.

LCMS condition : B.

Step 3)

(R)-tert-butyl (3-hydroxy- 1 -(4-((4-(2-hydroxyethoxy)phenyl)ethynyl)indolin- 1 -yl)- 1 - oxopropan-2-yl)carbamate

To a solution of (2R)-2-(tert-butoxycarbonylamino)-3-hydroxy-propanoic acid (51 mg) and HATU (0.12 g) in DMF (2.1 mL) were added DIPEA (0.11 mL) and 2-[4-(2-indolin-4- ylethynyl)phenoxy]ethanol hydrochloride (65 mg). The mixture was stirred for 3 hours at room temperature. The reaction was quenched with water and extracted with EtOAc. The organic layer was washed with water twice, dried over MgS0 ₄ , filtered and concentrated in vacuo. The residue was charged onto ISOLUTE® HM-N and purified with OH-type silica gel column chromatography (5-50 % EtOAc in n-hexane) to give the title compound (92 mg, 96 % yield) as a light yellow solid.

MS (ESI) m/z : 489 [M+23] ⁺ .

RT = 0.952 min.

LCMS condition : B.

Step 4)

(R)-tert-butyl (3 -hydroxy- 1 -(4-(4-(2-hydroxyethoxy)phenethyl)indolin- 1 -yl)- 1 -oxopropan-2- yl)carbamate

The solution of (R)-tert-butyl (3-hydroxy-l -(4-((4-(2-hydroxyethoxy)phenyl)ethynyl)indolin- l-yl)-l-oxopropan-2-yl)carbamate (68 mg) in MeOH was added palladium on carbon (7 mg). The reaction mixture was stirred under hydrogen atmosphere for 2 hours at room temperature. The mixture was filtered by a phase separator and rinsed with MeOH and EtOAc. The filtrate was concentrated in vacuo. The residue was charged onto ISOLUTE® HM-N and purified with OH-type silica gel column chromatography (5- 100 % EtOAc in n-hexane) to give the title compound (50 mg, 73 % yield) as a colorless solid.

MS (ESI) m/z : 493 [M+23] ⁺ .

RT = 0.944 min.

LCMS condition : B.

Step 5)

(2R)-2-amino-3-hydroxy-l-(4-{2-[4-(2-hydroxyethoxy)phenyl]et hyl}-2,3-dihydro-lH-indol- l

The title compound was obtained in the manner as with the "Synthesis of Compound- 1 : step- 7" using the corresponding materials.

Ή-NMR, MS and LCMS retention time data of Compound-16 are shown in Table 2.

Synthesis of Compound-27

(2R)-2-amino-3 -hydroxy- 1 - [6- { [4-(hydroxymethyl)phenyl]ethynyl } -3 ,4-dihydroisoquinolin- 2(lH)-yl]propan-l-one hydrochloride

Step 1)

Tert-butyl 6-((4-(hydroxymethyl)phenyl)ethynyl)-3,4-dihydroisoquinoline -2( 1 H)-carboxylate

A mixture of tert-butyl 6-bromo-3,4-dihydroisoquinoline-2(lH)-carboxylate (0.18 g), PdCl ₂ (PPh ₃ ) ₂ (82 mg), Cul (22 mg), triphenylphosphine (62 mg), hexamethyldisilazane (0.18 mL) and TEA (0.82 mL) in DMF (3 mL) was stirred at 110 °C. The mixture was stirred for 5 minutes, and then, (4-ethynylphenyl)methanol (0.23 g) was added into the mixture. The reaction mixture was stirred at the same temperature for 5 hours. After cooling the reaction mixture to room temperature, EtOAc (15 mL) and water (15 mL) were added and an organic layer was separated. The organic layer was washed with brine, dried over MgS0 ₄ and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (EtOAc in n-hexane) to give the title compound (0.12 g, 56 % yield) as a yellow solid.

MS (ESI) m/z : 386 [M+23 .

RT = 1.221 min.

LCMS condition : B. drochloride

The title compound was obtained in the manner as with the "Synthesis of Compound- 1 : step- 7" using the corresponding materials.

MS (ESI) m/z : 264 [M+l] ⁺ .

RT = 0.256 min.

LCMS condition : B.

Step 3)

(R)-tert-butyl (3 -hydroxy- 1 -(6-((4-(hydroxymethyl)phenyl)ethynyl)-3,4-dihydroisoquinoli n- 2(1 H)-yl)- 1 -oxopropan-2-yl)carbamate

The title compound was obtained in the manner as with the "Synthesis of Compound- 16: step-3" using the corresponding materials.

MS (ESI) m/z : 451 [M+l] ⁺ .

RT = 0.907 min.

LCMS condition : B.

Step 4)

(2R)-2-amino-3 -hydroxy- 1 - [6- { [4-(hydroxymethy l)phenyl] ethynyl } -3 ,4-dihydroisoquinolin- 2(1 H)-yl]propan- 1 -one hydrochloride (Compound-27)

The title compound was obtained in the manner as with the "Synthesis of Compound- 16: step-5" using the corresponding materials.

Ή-NMR, MS and LCMS retention time data of Compound-27 are shown in Table 2.

Synthesis of Compound-33

(R)-3-amino-4-((6-(4-(3-hydroxypropyl)phenyl)- 1 H-indol-3-yl)amino)-4-oxobutanoic acid

Step 1)

Tert-butyl (6-bromo- 1 H-indol-3 -yl)carbamate

0

To a solution of 6-bromo- lH-indole-3-carboxylic acid (2.5 g) in toluene (35 mL) and THF (35 mL) was added TEA (2.9 mL) at room temperature. After stirring the mixture for 10 minutes, DPP A (3.7 g) was added into the mixture and the resulting mixture was stirred for 3 hours at room temperature. The mixture was concentrated and the residue was dissolved in tert-butyl alcohol (21 mL) followed by addition of pyridine (2.9 mL). After the solution was refluxed for 3 hours, an additional pyridine (1.0 mL) was added and the mixture was refluxed for another 10 hours. The mixture was concentrated and the residue was dissolved in ethyl acetate and then washed with 0.5 mol/L aqueous HCI and half-saturated brine. The organic phase was separated, dried over MgS0 ₄ and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (10-50 % EtOAc in n-hexane) to give the title compound (1.6 g, 51 % yield) as a pale green solid.

MS (ESI) m/z : 31 1 [M+l] ⁺ .

RT = 1.081min.

LCMS condition : B.

Step 2)

Tert-but l (6-(4-(3-hydrox ro l) henyl)-lH-indol-3-yl)carbamate

A round bottomed flask was charged with tert-butyl (6-bromo-lH-indol-3-yl)carbamate

(0.75 g), [4-(3-hydroxypropyl)phenyl]boronic acid (0.56 g) and Pd(PPh ₃ ) ₄ (0.28 g). The flask was evacuated and backfilled with nitrogen followed by addition of EtOH (4.8 mL), toluene (19 mL) and 2 mol/L aqueous sodium carbonate (3.6 mL). The resulting mixture was heated to 90 °C for 3 hours and then allowed to cool to room temperature. The reaction mixture was poured into water and extracted three times with CHC1 ₃ . The combined organic layer was washed with a saturated aqueous sodium bicarbonate, dried over MgSCM and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (0-8 % MeOH in CHCI3) to give the title compound (0.24 g, 27 % yield) as a pale brown solid.

MS (ESI) m/z : 367 [M+l] ⁺ .

RT = 1.014min.

LCMS condition : B.

Step 3)

3-(4-(3-Amino-lH-indol-6-yl)phenyl)propan-l-ol hydrochloride

To a suspension of tert-butyl (6-(4-(3-hydroxypropyl)phenyl)-lH-indol-3 -yl)carbamate (0.23 g) in 1 ,4-dioxane (4.3 mL) was added 4 mol/L HCI in 1.4-dioxane (4.0 mL) at room temperature. After stirring for 3 hours, the reaction mixture was concentrated and the residue was co-evaporated with 1 ,4-dioxane to remove excess hydrogen chloride to give the title compound (0.19 g, crude) as a solid, which was used in next step without further purification. MS (ESI) m/z : 267 [M+l] ⁺ . RT = 0.696min.

LCMS condition : A.

Step 4)

(R)-benzyl 3 -(((benzyloxy)carbonyl)amino)-4-((6-(4-(3 -hydroxypropyl)phenyl)- 1 H-indol-3 - yl)amino)-4-oxobutanoate

To a solution of Z-D-Asp(OBzl)-OH (0.15 g) and 3-(4-(3-amino- 1 H-indol-6- yl)phenyl)propan-l-ol hydrochloride (0.17 g) in DMF (1.4 mL) were sequentially added NMM (0.21 g) and T3P (0.32 mL, 50 wt% in EtOAc) at room temperature. After stirring for 16 hours, the mixture was diluted with CHC1 ₃ and then washed with 5% aqueous sodium bicarbonate and brine. The organic phase was separated, dried over MgS0 ₄ and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (40-80 % EtOAc in n-hexane) to give the title compound (54 mg, 21 % yield) as a colorless oil.

MS (ESI) m/z : 606 [M+l] ⁺ .

RT = l.HOmin.

LCMS condition : B.

Step 5)

(R)-3-amino-4-((6-(4-(3-hydroxypropyl)phenyl)-lH-indol-3-yl) amino)-4-oxobutanoic acid (Compound-33)

To a solution of (R)-benzyl 3-(((benzyloxy)carbonyl)amino)-4-((6-(4-(3- hydroxypropyl)phenyl)-lH-indol-3-yl)amino)-4-oxobutanoate (53 mg) in MeOH (4.0 mL) was added 10% Pd-C (15 mg) under inert atmosphere. The flask was flushed with hydrogen gas and the mixture was vigorously stirred for 3 hours at ambient temperature. The reaction mixture was filtered through a pad of Celite® and the cake was washed with MeOH. The filtrate was concentrated under reduced pressure to give the title compound (Compound-33, 1 1 mg, 33 % yield) as a colorless solid.

Ή-NMR, MS and LCMS retention time data of Compound-33 are shown in Table 2.

Synthesis of Compound-42

2-Amino-2-(l , 1 -dioxidothiomorpholin-3-yl)-l -(4-(4-methylbenzyl)piperidin-l -yl)ethanone

Compound-42

Step 1)

2-((Tert-butoxycarbonyl)amino)-2-(4-(tert-butoxycarbonyl)thi omorpholin-3-yl)acetic acid

.1) (NH ₄ ) ₂ C0 ₃ aq KCN, MeOH

To a solution of tert-butyl 3-formylthiomorpholine-4-carboxylate (1.0 g) in MeOH (10 mL) was added 10 % aqueous ammonium carbonate (10 mL). The reaction mixture was stirred at 0°C for 1 hour and then potassium cyanide (0.45 g) was added into the mixture. After stirring for 1 hour, the mixture was allowed to warm to room temperature and stirred for 1.5 hour. The mixture was concentrated in vacuo and the residue was diluted with water and extracted with EtOAc. The organic phase was dried over MgS0 ₄ and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (25-40 % EtOAc in n- hexane) to give a crude product (98 mg), which was used in the next step.

To a solution of the crude product (98 mg) and (Boc) ₂ 0 (0.21 g) in THF (6 mL) were sequentially added TEA (50 μΐ,) and DMAP (3.9 mg). The reaction mixture was stirred at room temperature overnight and concentrated in vacuo. The residue was used in the next step without further purification.

To the crude product dissolved in THF (2 mL) was added 1 mol/L aqueous lithium hydroxide (2 mL). The mixture was stirred at room temperature for 2.5 hour and then heated to 70°C and stirred for 1 hour. After cooling to room temperature, the mixture was concentrated in vacuo to obtain a crude residue (20 mg), which was used in next step without further purification.

To the crude product (20 mg) in THF (2 mL) were sequentially added 1 mol/L aqueous sodium hydroxide (2 mL) and (Boc) ₂ 0 (0.29 g) and the mixture was stirred at room temperature for 2 days. The mixture was diluted with CHC (15 mL) and extracted with a saturated aqueous sodium bicarbonate (15 mL) twice. The combined aqueous phase was adjusted to pH 2 with 1 mol/L aqueous potassium hydrogen sulfate. The resulting mixture was extracted with EtOAc (15 mL) twice. The combined organic extracts were combined, dried over MgS0 ₄ and concentrated in vacuo to give the title compound (15 mg, 2.8 % yield in 4 steps) as a colorless amorphous.

MS (ESI) m/z : 399 [M+23] ⁺ .

RT = 1.040 min and 1.367 min (each diastereomer peak was observed).

LCMS condition : B.

Step 2)

Tert-butyl 3 -( 1 -((tert-butoxycarbonyl)amino)-2-(4-(4-methylbenzyl)piperidin - 1 -yl)-2- oxoethyl)thiomorpholine-4-carboxylate

To a solution of 4-(4-methyl-benzyl)-piperidine hydrochloride (11 mg) in DMF (2 mL) were sequentially added HATU (20 mg) and DIPEA (25 μί) at room temperature. After stirring the mixture for 30 minutes, 2-((tert-butoxycarbonyl)amino)-2-(4-(tert- butoxycarbonyl)thiomorpholin-3-yl)acetic acid (15 mg) was added into the mixture. The mixture was stirred for 6 hours and diluted with EtOAc and then washed with a saturated aqueous sodium bicarbonate and brine. The organic phase was separated, dried over MgS0 ₄ and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (10-50 % EtOAc n-hexane) to give the title compound (10 mg, 46 % yield). MS (ESI) m/z : 548 [M+l] ⁺ .

RT = 1.061 min.

LCMS condition : C.

Step 3)

Tert-butyl 3 -( 1 -((tert-butoxycarbonyl)amino)-2-(4-(4-methylbenzyl)piperidin - 1 -yl)-2- oxoethyl)thiomorpholine-4-carboxylate 1 , 1 -dioxide

To a cooled (0 °C) solution of tert-butyl 3-(l-((tert-butoxycarbonyl)amino)-2-(4-(4- methylbenzyl)piperidin-l-yl)-2-oxoethyl)thiomoφholine-4-car boxylate (23 mg) in CHCI3 (2 mL) was added 3-chloroperbenzoic acid (21 mg). After stirring for 5 minutes at 0 °C, the mixture was allowed to warm to room temperature and stirred for 6 hours. The reaction was quenched with 2% aqueous sodium thiosulfate (5mL) and a saturated aqueous sodium bicarbonate, and extracted with CHC1 ₃ . The organic layers were dried over MgS0 ₄ and concentrated in vacuo. The residue was purified with amino-type silica gel column chromatography (20-80 % EtOAc in n-hexane) to give the title compound (9.0 mg, 37 % yield) as a colorless amorphous.

MS (ESI) m/z : 580 [M+l] ⁺ .

RT = 0.972 min and 0.997min (each diastereomer peak was observed).

LCMS condition : C.

Step 4)

2-Amino-2-( 1 , 1 -dioxidothiomorpholin-3-yl)- 1 -(4-(4-methylbenzyl)piperidin- 1 -yl)ethanone (Compound-42)

The title compound was obtained in the manner as with the "Synthesis of Compound- 16: step-5" using the corresponding materials.

MS and LCMS retention time data of Compound-42 are shown in Table 3.

Synthesis of Compound-48

2-Amino-2-[3-hydroxy- 1 -(methanesulfonyl)pyrrolidin-3-yl]- 1 - {4-[(4- methylphenyl)methyl]piperidin-l-yl}ethan-l-one

Step 1)

Tert-butyl 3 -( 1 -(dibenzylamino)-2-(4-(4-methylbenzyl)piperidin- 1 -yl)-2-oxoethyl)-3-

To a stirred solution of diisopropylamine (0.15 mL) in THF (6.6 mL) was added 1.6 mol/L n- butyllithium in hexane (0.62 mL) at -78 °C. The reaction mixture was allowed to warm to 0°C and was stirred for 30 minutes. The reaction mixture was then cooled at -78 °C and 2- (dibenzylamino)-l-[4-(p-tolylmethyl)-l-piperidyl]ethanone (0.28 g) in THF was added into the mixture. After stirring the mixture for 30 minutes, tert-butyl 3-oxopyrrolidine-l- carboxylate (0.15 g) in THF was added into the mixture. The reaction mixture was allowed to warm to room temperature and stirred further 2 hours. The mixture was quenched with a saturated aqueous sodium bicarbonate and extracted three times with CHCI3. The organic layer was passed through a phase separator and concentrated in vacuo onto ISOLUTE® HM- N. The residue was purified with OH-type silica gel column chromatography (8-66 % EtOAc in n-hexane) to give the title compound as a separated single diastereomer (0.18 g, 44 % yield as a low-polar diastereomer (oil) and 84 mg, 21 % yield as a high-polar diastereomer (oil), respectively). The high-polar diastereomer was used in the next step.

High-polar diastereomer:

¾ NMR (400 MHz, CHLOROFORM-d) δ ppm 0.79 - 1.19 (m, 2 H), 1.38 - 1.90 (m, 15 H), 2.26 - 2.95 (m, 6 H), 3.10 - 3.97 (m, 7 H), 4.27 - 4.46 (m, 2 H), 4.64 - 4.85 (m, 1 H), 5.06 - 5.38 (m, 1 H), 6.90 - 7.55 (m, 14 H).

Step 2)

2-(Dibenzylamino)-2-(3 -hydroxypyrrolidin-3 -yl)- 1 -(4-(4-methylbenzyl)piperidin- 1 -

To a stirred solution of tert-butyl 3-[l-(dibenzylamino)-2-oxo-2-[4-(p-toIylmethyl)-l- piperidyl]ethyl]-3-hydroxy-pyrrolidine-l-carboxylate (84 mg, high-polar diastereomer) in 1,4-dioxane (1.4 mL) was added 4 mol/L hydrogen chloride in 1,4-dioxane (0.34 mL). After stirring for 2 hours at room temperature, the reaction mixture was quenched with a saturated aqueous sodium bicarbonate and extracted with CHC1 ₃ three times. The organic layer was passed through a phase separator and concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with amino-type silica gel column chromatography (0-9 % MeOH in EtOAc) to give the title compound (86 mg, quant.) as an oil.

MS (ESI) m/z : 512 [M+l] ⁺ .

RT = 0.972 min.

LCMS condition : B.

Step 3)

2-(Dibenzylamino)-2-(3 -hydroxy- 1 -(methylsulfonyl)pyrrolidin-3 -yl)- 1 -(4-(4- methylbenzyl)piperidin- 1 -yl)ethanone

To a stirred solution of 2-(dibenzylamino)-2-(3-hydroxypyrrolidin-3-yl)-l -[4-(p- tolylmethyl)-l-piperidyl]ethanone (86 mg) in CHC1 ₃ (3.4 mL) were added TEA (0.12 mL) and methanesulfonyl chloride (20 μί) at 0 °C. After stirring for 5 hours at room temperature, the reaction mixture was quenched with a saturated aqueous sodium bicarbonate and extracted twice with CHC1 ₃ . The organic layer was passed through a phase separator and concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with OH-type silica gel column chromatography (8-51 % EtOAc in n-hexane) to give the title compound (63 mg, 64 % yield) as an oil.

MS (ESI) m/z 590 [M+l] ⁺ .

RT = 1.440 min.

LCMS condition : B.

Step 4)

2-Amino-2-[3-hydroxy- 1 -(methanesulfonyl)pyrrolidin-3-yl]- 1 - {4-[(4-

To a solution of 2-(dibenzylamino)-2-(3-hydroxy-l-methylsulfonyl-pyrrolidin-3 -yl)-l-[4-(p- tolylmethyl)-l-piperidyl]ethanone (63 mg) in MeOH (0.53 mL) was added palladium hydroxide on carbon (20 mg). The mixture was stirred at room temperature for 2 hours under hydrogen atmosphere. The reaction mixture was filtered and filtrate was concentrated in vacuo. The residue was diluted with CHCI3 and washed with a saturated aqueous sodium bicarbonate. The organic layer was concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with amino-type silica gel column chromatography (2-14 % MeOH in CHCI3) to give the title compound (30 mg, 69 % yield) as a colorless powder.

MS and LCMS retention time data of Compound-48 are shown in Table 3.

Synthesis of Compound-61

2-Amino-2-[4-hydroxy- 1 -(methanesulfonyl)piperidin-4-yl]- 1 -{4-[(4- methylphenyl)methyl]piperidin- 1 -yl } ethan- 1

Step 1)

Tert-butyl 4-(2-(4-(4-methylbenzyl)piperidin- 1 -yl)-2-oxoethylidene)piperidine- 1 -carboxylate

The title compound was obtained in the manner as with the "Synthesis of Compound- 16: step-3" using the corresponding materials.

MS (ESI) m/z : 413 [M+l] ⁺ , 435 [M+23] ⁺ .

RT = 1.285 min.

LCMS condition : B.

Step 2)

1 -(4-(4-Methylbenzyl)piperidin- 1 -yl)-2-( 1 -(methylsulfonyl)piperidin-4-ylidene)ethanone

To a solution of tert-butyl 4-(2-(4-(4-methylbenzyl)piperidin-l-yl)-2- oxoethylidene)piperidine-l -carboxylate (0.86 g) in 1 ,4-dioxane (4 mL) was added 4 mol/L HC1 in 1 ,4-dioxane (8 mL). The mixture was stirred at room temperature for 2.5 hours. The reaction mixture was quenched with aqueous potassium carbonate under ice-bath cooling and extracted with CHC1 ₃ . The organic phase was separated, dried over MgS0 ₄ and concentrated in vacuo to give a crude product (0.63 g) as a light yellow syrup, which was used in the next step without further purification.

To a solution of the crude product (0.63 g) in CHC1 ₃ (10 mL) were added DIEA (1.5 mL) and methanesulfonyl chloride (0.21 μί) at 0 °C. After stirring for 1 hour at room temperature under nitrogen atmosphere, the reaction mixture was quenched with a saturated aqueous sodium bicarbonate and extracted with CHCb. The organic layer was passed through a phase separator and concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with OH-type silica gel column chromatography (30-100 % EtOAc in n-hexane and then 2-10 % MeOH in CHC1 ₃ ) to give the title compound (0.65 g, 80 % yield in 2 steps) as a yellow syrup. MS (ESI) m/z : 391 [M+l] ⁺ , 413 [M+23] ⁺ .

RT = 1.045 min.

LCMS condition : B.

Step 3)

(4-(4-Methylbenzyl)piperidin-l-yl)(6-(methylsulfonyl)-l-oxa- 6-azaspiro[2.5]octan-2- yl)methanone

To a solution of l-(4-(4-methylbenzyl)piperidin-l-yl)-2-(l-(methylsulfonyl)pi peridin-4- ylidene)ethanone (0.45 g) in 1 ,2-dichloroethane (20 mL) was added m-chloroperbenzoic acid (0.40 g) and the mixture was stirred overnight at room temperature. m-Chloroperbenzoic acid (0.16 g) was added into the mixture and the mixture was stirred for 8 hours. The reaction mixture was quenched with aqueous sodium thiosulfate and extracted with CHC1 ₃ . The organic phase was washed with aqueous sodium thiosulfate and saturated aqueous sodium bicarbonate twice, passed through a phase separator and concentrated in vacuo onto

ISOLUTE® HM-N. The residue was purified with OH-type silica gel column

chromatography (2-15 % MeOH in CHC1 ₃ ) to give the title compound (0.43 g, 91 % yield) as a brown amorphous.

MS (ESI) m/z : 407 [M+l] ⁺ , 429 [M+23] ⁺ .

RT = 0.988 min.

LCMS condition : B.

Step 4)

2-(Benzylamino)-2-(4-hydroxy-l-(methylsulfonyl)piperidin- 4-yl)-l-(4-(4- methylbenzyl)piperidin- 1 -yl)ethanone

To a solution of (4-(4-methylbenzyl)piperidin- 1 -yl)(6-(methylsulfonyl)- 1 -oxa-6- azaspiro[2.5]octan-2-yl)methanone (0.42 g) in MeOH (7 mL) and THF (7 mL) was added benzylamine (2 mL). The mixture was stirred for 90 minutes at 140 °C under microwave irradiation. After cooling to room temperature, the reaction mixture was concentrated in vacuo onto ISOLUTE® HM-N. The residue was purified with OH-type silica gel column chromatography (30-100 % AcOEt in n-hexane and then 2-5 % MeOH in CHC1 ₃ ) to give a crude product, which was re-purified with OH-type silica gel column chromatography (40- 100 % AcOEt in n-hexane) to give the title compound (76 mg, 14 % yield) as a light yellow syrup.

MS (ESI) m/z : 514 [M+l] ⁺ .

RT = 0.752 min.

LCMS condition : B.

Step 5)

2-Amino-2-[4-hydroxy-l-(methanesulfonyl)piperidin-4-yl]-l-{4 -[(4- 1 )

To a solution of 2-(benzylamino)-2-(4-hydroxy-l-(methylsulfonyl)piperidin-4-y l)-l-(4-(4- methylbenzyl)piperidin-l-yl)ethanone (50 mg) in MeOH (1 mL) was added palladium hydroxide on carbon (6 mg). The mixture was stirred at room temperature for 1 hour under hydrogen atmosphere. Palladium hydroxide on carbon (25 mg) was added into the mixture and the mixture was stirred at room temperature for 5 hours under hydrogen atmosphere. To another solution of 2-(benzylaminO)-2-(4-hydroxy- 1 -(methylsulfonyl)piperidin-4-yl)- 1 -(4-(4- methylbenzyl)piperidin-l-yl)ethanone (25 mg) in MeOH (1 mL) was added palladium hydroxide on carbon (25 mg) and the mixture was stirred at room temperature overnight under hydrogen atmosphere. The two reaction mixtures were combined and filtered through Celite®. The filtrate was concentrated in vacuo and the residue was purified with preparative chromatography (7% MeOH in CHC1 ₃ ) to give the title compound (Compound-61, 30 mg, 49 % yield) as a colorless solid.

MS and LCMS retention time data of Compound-53 are shown in Table 3.

Synthesis of Compound-89

N- [3 -(trifluoromethoxy)phenyl] -D-serinamide

Compound-89

Step 1)

(R)-tert-butyl (3 -hydroxy- 1 -oxo- 1 -((3 -(trifluoromethoxy)phenyl)amino)propan-2-

The title compound was obtained in the manner as with the "Synthesis of Compound- 16: step-3" using the corresponding materials.

MS (ESI) m/z : 387 [M+23] ⁺ .

RT = 0.980 min.

LCMS condition : B.

Step 2)

The title compound was obtained in the manner as with the "Synthesis of Compound- 16: step-5" using the corresponding materials.

MS and LCMS retention time data of Compound-89 are shown in Table 3.

Synthesis of Compound-99

} -D-serinamide

Step 1)

3-(4-(Phenylethynyl)phenoxy)aniline

A flask was charged with 1 -iodo-4-(phenylethynyl)benzene (0.40 g), 3-aminophenol (0.22 g), Cul (75 mg), pyridine-2-carboxylic acid (97 mg) and K3PO4 (0.56 g). The flask was evacuated and backfilled with nitrogen followed by addition of DMSO (2.6 mL). After stirring for 3 hours at 90 °C, the mixture was diluted with EtOAc, filtered through a pad of Celite® and rinsed with EtOAc. The filtrate was sequentially washed with half-saturated aqueous ammonium chloride, water and brine. The organic phase was separated, dried over MgS0 ₄ , filtered and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (20-80 % EtOAc n-hexane) to give the title compound (0.31 g, 83 % yield) as a pale yellow solid.

MS (ESI) m/z : 286 [M+l] ⁺ .

RT = 1.270min.

LCMS condition : B.

Step 2)

(R)-tert-butyl (3-Hydroxy-l-oxo-l-((3-(4-(phenylethynyl)phenoxy)phenyl)amin o)propan -2-yl)carbamate

To a solution of 3-(4-(Phenylethynyl)phenoxy)aniline (0.15 g) in DMF were sequentially added Boc-D-Ser-OH (80 mg), NMM (0.12 g) and T3P (0.30 mL, 50 wt% in EtOAc) at room temperature. After stirring for 48 hours, the mixture was diluted with EtOAc and then washed with 5% aqueous sodium bicarbonate, water and brine. The organic phase was separated, dried over MgS0 ₄ and concentrated in vacuo. The residue was purified with OH-type silica gel column chromatography (20-80 % EtOAc n-hexane) to give the title compound (67 mg, 36 % yield) as an amorphous.

MS (ESI) m/z : 495 [M+23] ⁺ .

RT = 1.269min.

LCMS condition : B.

Step 3)

N- { 3- [4-(phenylethynyl)phenoxy]phenyl } -D-serinamide (Compound-99)

Compound-99

A solution of (R)-tert-butyl (3 -hydroxy- 1 -oxo- 1 -((3 -(4-

(phenylethynyl)phenoxy)phenyl)amino)propan-2-yl)carbamate (66 mg) in formic acid (1.0 mL) was stirred for 2 hours. The reaction mixture was concentrated and the residue was co- evaporated twice with CHC1 ₃ . The residue was dissolved in MeOH-CHCl ₃ (1 : 1) followed by addition of BIOTAGE® MP-TsOH. After stirring for 16 hours, the resin was collected, washed with MeOH-CHC (1 :1) and MeOH, and then eluted with 7 mol/L ammonia in MeOH to give the title compound (Compound-99, 39 mg, 76 % yield) as a pale yellow oil. MS and LCMS retention time data of Compound-99 are shown in Table 3.

Example Compounds in Table 2 and Table 3 were obtained in a manner as with above experimental procedures or general procedures using the corresponding materials.

Table 2. Example Compounds (Compound- 1 to Compound-33). Compound ID, chemical structures, 'H-NMR data, MS data and LCMS retention time (minutes) data are shown.

Compound- 1 :

2-amino-3-hydroxy-l-{4-[(4-{ [4-(hydroxymethyl)phenyl]ethynyl}phenyl)methyl]piperidin- Γ-yl} -4-(methanesulfonyl)butan- 1 -one

Compound-2 :

(2R)-2-amino-3 -hydroxy- 1 -(4- { [4-({4-[(morpholin-4- yl)methyl]phenyl}ethynyl)phenyl]methyl}piperidin-l -yl)propan-l-one 2 hydrochloride Compound-3 :

(2R)-2-amino-3 -hydroxy- 1 - {4- [(4- { [4-

(hydroxymethyl)phenyl]ethynyl } phenyl)methyl]piperidin- 1 -yl } propan- 1 -one hydrochloride Compound-4 :

(2R)-2-amino-3 -hydroxy- 1 - { 4- [(4- { [4-(2- hydroxyethoxy)phenyl]ethynyl }phenyl)methyl]piperidin- 1 -yl } propan- 1 -one

Compound-5 :

(2R)-2-amino- 1 - {4- [(4- { [4-(3 -hydroxypropyl)phenyl] ethynyl } phenyl)methyl]piperidin- 1 - yl } -4-(methylsulfanyl)butan- 1 -one

Compound-6 :

(2R)-2-amino- 1-{4-[(4-{ [4-(2-hydroxyethoxy)pheny 1] ethynyl } phenyl)methy 1] piperidin- 1 - yl } -4-(methanesulfonyl)butan- 1 -one

Compound-7 :

(2R)-2-amino-3 -hydroxy- 1 -(4- { [4-(phenylethynyl)phenyl]methyl }piperidin- 1 -yl)propan- 1 - one hydrochloride

Compound-8 :

(2R)-2-amino-l-{4-[(4-{ [4-(hydroxymethyl)phenyl]ethynyl}phenyl)methyl]piperidin-l-y l}- 4-(methanesulfonyl)butan- 1 -one formate

Compound-9 :

2-amino-3 -hydroxy-4-(methanesulfonyl)- 1 -(4- { [4-(prop- 1 -yn- 1 -yl)phenyl] methyl } piperidin- l-yl)butan-l-one hydrochloride

Compound- 10 :

(2R)-2-amino-4-(methanesulfonyl)- 1 -(4- { [4-(phenylethynyl)phenyl]methyl } piperidin- 1 - yl)butan-l-one

Compound- 1 1 :

(2R)-2-amino-3 -hydroxy- 1 -(4- { [4'-(3 -hydroxypropyl) [1 ,1 '-biphenyl] -4-yl] methyl } piperidin- l-yl)propan-l-one hydrochloride

Compound- 12 :

(2R)-2-amino-4-(methylsulfanyl)- 1 -(4- { [4-(phenylethynyl)phenyl]methyl}piperidin- 1 - yl)butan-l-one

Compound- 13 :

(2R)-2-amino-l -{4-[(4-{ [4-(hydroxymethyl)phenyl]ethynyl}phenyl)methyl]piperidin-l - yl}pentan-l -one formate Compound- 14 :

2-amino-3 -hydroxy-4-(methanesulfonyl)- 1 - {4- [(4-methylphenyl)methyl]piperidin- 1 - yl}butan-l-one

Compound- 15 :

(2R)-2-amino-3 -hydroxy- 1 - [4-(2-phenylethyl)-2,3 -dihydro- 1 H-indol- 1 -yl]propan- 1 -one Compound- 16 :

(2R)-2-amino-3 -hydroxy- 1 -(4- { 2- [4-(2-hydroxyethoxy)phenyl]ethyl} -2,3 -dihydro- 1 H-indol-

1- yl)propan-l-one hydrochloride

Compound- 17 :

(2R)-2-amino- 1 -[4-(3 -chlorophenoxy)-2,3 -dihydro- 1 H-indol- 1 -yl] -3 -hydroxypropan- 1 -one Compound- 18 :

(2R)-2-amino-3 -hydroxy- 1 - [4-(3-phenylpropyl)-2,3 -dihydro- 1 H-indol- 1 -yl]propan- 1 -one Compound- 19 :

(2R)-2-amino-4-(methanesulfonyl)- 1 -[4-(2-phenylethyl)-2,3-dihydro- 1 H-indol- 1 -yl]butan- 1 - one

Compound-20 :

(2R)-2 -amino- 1 -[4-(3-chlorophenoxy)-2,3-dihydro- 1 H-indol- 1 -yl]-4- (methanesulfonyl)butan- 1 -one

Compound-21 :

(3R)-3-amino-4-(4-{2-[4-(2-hydroxyethoxy)phenyl]ethyl} -2,3-dihydro-l H-indol- 1 -yl)-4- oxobutanoic acid

Compound-22 :

(2R)-2-amino-3 -hydroxy- 1 -[4-(phenoxymethyl)-2,3-dihydro- 1 H-indol- 1 -yl]propan- 1 -one Compound-23 :

(3R)-3-amino-4-oxo-4-[4-(2-phenylethyl)-2,3-dihydro-lH-in dol-l-yl]butanoic acid

Compound-24 :

2- amino-3-hydroxy-l-[6-{[4-(2-hydroxyethoxy)phenyl]ethynyl}-3, 4-dihydroisoquinolin- 2(1 H)-yl] -4-(methanesulfonyl)butan- 1 -one

Compound-25 :

(2R)-2-amino-3 -hydroxy- 1 - [6- { [4-(2-hydroxyethoxy)phenyl]ethynyl } -3 ,4- dihydroisoquinolin-2(lH)-yl]propan-l-one hydrochloride

Compound-26 :

(2R)-2-amino-3 -hydroxy- 1 - [6-(phenylethynyl)-3 ,4-dihydroisoquinolin-2( 1 H)-yl]propan- 1 - one

Compound-27 :

(2R)-2-amino-3-hydroxy- 1 - [6- { [4-(hydroxymethyl)phenyl]ethynyl } -3 ,4-dihydroisoquinolin- 2(lH)-yl]propan-l -one hydrochloride Compound-28 :

(2R)-2-amino-3 -hydroxy- 1 -(6-phenyl-3 ,4-dihydroisoquinolin-2( 1 H)-yl)propan- 1 -one Compound-29 :

(2R)-2-amino-N- { 6-[4-(3 -hydroxypropyl)phenyl] - 1 H-indol-3 -yl } -4- (methanesulfonyl)butanamide

Compound-30 : N-(6-phenyl-l H-indol-3 -yl)-D-serinamide

Compound-31 : N-{6-[4-(3-hydroxypropyl)phenyl]-lH-indol-3-yl}-D-serinamide

Compound-32 : N-[6-(phenylethynyl)-lH-indol-3-yl]-D-serinamide

Compound-33 :

(R)-3-amino-4-((6-(4-(3-hydroxypropyl)phenyl)-l H-indol-3 -yl)amino)-4-oxobutanoic acid Table 3. Example Compounds (Compound-34 to Compound- 104). Compound ID, chemical

Compound-34 :

(2R)-2-amino- 1 - {4- [(4- { [4-(3 -hydroxypropyl)phenyl]ethynyl } phenyl)methyl]piperidin- 1 - yl}-3-(l ,3-thiazol-4-yl)propan- 1 -one

Compound-35 :

(2R)-2,3-diamino- 1-{4-[(4- { [4-(hydroxymethyl)phenyl]ethynyl}phenyl)methyl]piperidin- 1 - yl}propan-l-one formate

Compound-36 : (3R)-3-amino-4-oxo-4-(4-{ [4-(phenylethynyl)phenyl]methyl}piperidin-l -yl)butanoic acid formate

Compound-37 :

(2R)-2-amino- 1 -(4- { [4-(phenylethynyl)phenyl]methyl } piperidin- 1 -yl)pentan- 1 -one

Compound-38 :

(2R)-2-amino- 1 - {4-[([ 1 , 1 '-biphenyl]-4-yl)methyl]piperidin- 1 -yl } -3-hydroxypropan- 1 -one hydrochloride

Compound-39 :

(2R)-2-amino- 1 -(4- { [4-(phenylethynyl)phenyl] methyl } piperidin- 1 -yl)-3 -( 1 ,3 -thiazol-4- yl)propan-l-one

Compound-40 :

(3R)-3 -amino-4- {4- [(4- { [4-(hydroxymethyl)phenyl] ethynyl } phenyl)methyl]piperidin- 1 -yl} - 4-oxobutanoic acid

Compound-41 :

(2R)-2,3-diamino- 1 -(4- { [4-(phenylethynyl)phenyl]methyl }piperidin- 1 -yl)propan- 1 -one 2 hydrochloride

Compound-42 :

2-amino-2-( 1 , 1 -dioxidothiomorpholin-3 -yl)- 1 -(4-(4-methylbenzyl)piperidin- 1 -yl)ethanone Compound-43 :

(2R)-2-amino-l-[4-({4-[([l,l'-biphenyl]-4-yl)methoxy]phen yl}methyl)piperidin-l-yl]-3- hydroxypropan- 1 -one hydrochloride

Compound-44 :

(2R)-2-amino- 1 - {4-[(4-methylphenyl)methyl]piperidin- 1 -yl} -4-(methylsulfanyl)butan- 1 -one Compound-45 :

(2R)-2-amino-3-hydroxy-l-{4-[(4-methylphenyl)methyl]piper idin-l-yl}propan-l-one hydrochloride

Compound-46 :

(2R)-2-amino-3 -hydroxy- 1 - { 4-[(4-phenoxyphenyl)methyl]piperidin- 1 -yl } propan- 1 -one hydrochloride

Compound-47 :

2-amino-2-(3 -hydroxy- 1 , 1 -dioxidotetrahydro-2H-thiopyran-3-yl)-l -(4-(4- methylbenzyl)piperidin- 1 -yl)ethanone formate

Compound-48 :

2-amino-2- [3 -hydroxy- 1 -(methanesulfonyl)pyrrolidin-3 -yl] - 1 - { 4- [(4- methylphenyl)methyl]piperidin-l-yl}ethan-l-one

Compound-49 :

(2R)-2-amino-4-(methanesulfonyl)-l -{4-[(4-methylphenyl)methyl]piperidin-l-yl}butan-l- one

Compound-50 :

2-amino-2-(3-hydroxy- 1 , 1 -dioxidotetrahydrothiophen-3-yl)- 1 -(4-(4-methylbenzyl)piperidin-

1- yl)ethanone

Compound-51 :

(2R)-2-amino-3 -hydroxy- 1 -(4- { [4-(2-phenylethyl)phenyl]methyl}piperidin- 1 -yl)propan- 1 - one hydrochloride

Compound-52 :

(2R)-2-amino-l-(4-{[4-(phenylethynyl)phenyl]methyl}piperidin -l-yl)-3-(2H-tetrazol-5- yl)propan-l-one hydrochloride

Compound-53 :

(2R,3 S)-2-amino-3 -hydroxy- 1 - {4- [(4-methylphenyl)methyl]piperidin- 1 -yl } butan- 1 -one Compound-54 :

2- amino-3 -hydroxy- 1 -(4-(4-methylbenzyl)piperidin- 1 -yl)-4-(methylsulfonyl)butan- 1 -one Compound-55 :

(2R)-2-amino- 1 - {4-[(4-ethylphenyl)methyl]piperidin- 1 -yl } -3 -hydroxypropan- 1 -one hydrochloride

Compound-56 : (2R,3 S)-2-amino-3 -hydroxy- 1 -(4-(4-methylbenzyl)piperidin- 1 -yl)butan- 1 - one

Compound-57 :

(2R)-2-amino- 1 - { 4- [(4-methylphenyl)methyl]piperidin- 1 -yl } -3 -( 1 ,3-thiazol-4-yl)propan- 1 - one 2 hydrochloride

Compound-58 : (3R)-3-amino-4-{4-[(4-methylphenyl)methyl]piperidin-l-yl}-4- oxobutanoic acid formate

Compound-59 :

2-amino-2-(3-hydroxy- 1 -(methylsulfonyl)pyrrolidin-3-yl)- 1 -(4-(4-methylbenzyl)piperidin- 1 - yl)ethanone

Compound-60 :

2-amino- 1 - {4- [(4-methylpheny l)methyl]piperidin- 1 -yl } -3 -(pyridin-2-yl)propan- 1 -one 2 hydrochloride

Compound-61 :

2-amino-2-[4-hydroxy- 1 -(methanesulfonyl)piperidin-4-yl] - 1 -{4-[(4- methylphenyl)methyl]piperidin- 1 -yl } ethan- 1 -one

Compound-62 :

(2R)-2-amino- 1 - { 4- [( [ 1 , 1 '-biphenyl]-4-yl)methylidene]piperidin- 1 -yl } -3 -hydroxypropan- 1 - one hydrochloride

Compound-63 : (2R)-2-amino- 1 - {4-[(4-bromophenyl)methylidene]piperidin- 1 -yl} -3-hydroxypropan- 1 -one hydrochloride

Compound-64 :

(2R)-2-amino-3 -hydroxy- 1 - [4-(3 -phenylprop- 1 -yn- 1 -yl)-2,3 -dihydro- 1 H-indol- 1 -yljpropan- 1-one

Compound-65 : (2R)-2-amino- 1 - [4-(benzyloxy)-2 ,3 -dihydro- 1 H-indol- 1 -yl] -3 - hydroxypropan- 1 -one

Compound-66 :

(2R)-2-amino- 1 - [4-(2-phenylethyl)-2,3 -dihydro- 1 H-indol- 1 -yl] -3 -(2H-tetrazol-5-yl)propan- 1-one hydrochloride

Compound-67 : (2R)-2,3-diamino-l-[4-(2-phenylethyl)-2,3-dihydro-lH-indol-l -yl]propan-l- one

Compound-68 :

2-amino- 1 -[4-(2-phenylethyl)-2,3 -dihydro- 1 H-indol- 1 -yl] -3 -(pyridin-2-yl)propan- 1 -one hydrochloride

Compound-69 : (2R)-2-amino- 1 -(4-bromo-2,3 -dihydro- 1 H-indol- 1 -yl)-3 -hydroxypropan- 1 - one

Compound-70 :

(2R)-2-amino-3 -hydroxy- 1 -(4- { [4-(2-hydroxyethoxy)phenyl]ethynyl} -2,3-dihydro- 1 H-indol- l-yl)propan- 1-one hydrochloride

Compound-71 :

(2R)-2-amino-3 -hydroxy- 1 -[4-(phenylethynyl)-2,3-dihydro- 1 H-indol- 1 -yl]propan- 1 -one Compound-72 :

(2R)-2-amino-4-(methanesulfonyl)- 1 -[4-(phenylethynyl)-2,3 -dihydro- 1 H-indol- 1 -yl]butan- 1 - one

Compound-73 : (2R)-2-amino-3-hydroxy-l-(4-phenyl-2,3-dihydro-lH-indol-l-yl )propan-l- one

Compound-74 :

(3R)-3-amino-4-(4-bromo-2,3-dihydro-lH-indoi-l-yl)-4-oxobuta noic acid trifluoroacetate Compound-75 :

(2R)-2-amino- 1 -(4-bromo-2,3-dihydro- 1 H-indol- 1 -yl)-4-(methanesulfonyl)butan- 1 -one hydrochloride

Compound-76 :

(3 R)-3 -amino-4- [6- { [4-(2-hydroxyethoxy)phenyl]ethynyl } -3 ,4-dihydroisoquinolin-2( 1 H)- yl]-4-oxobutanoic acid

Compound-77 :

(2R)-2-amino-l-[6-{[4-(hydroxymethyl)phenyl]ethynyl}-3,4-dih ydroisoquinolin-2(lH)-yI]- 4-(methanesulfonyl)butan- 1 -one

Compound-78 :

(2R)-2-amino-3 -hydroxy- 1 - [6-(2-phenylethyl)-3 ,4-dihydroisoquinolin-2( 1 H)-yl]propan- 1 - one

Compound-79 :

(2R)-2-amino-3 -hydroxy- 1 - { 6- [4-(3-hydroxypropyl)phenyl]-3 ,4-dihydroisoquinolin-2( 1 H)- yl}propan-l-one hydrochloride

Compound- 80 :

(2R)-2-amino- 1 -(6-bromo-3 ,4-dihydroisoquinolin-2( 1 H)-yl)-4-(methanesulfonyl)butan- 1 -one Compound-81 :

(2R)-2-amino- 1 -(6-bromo-3 ,4-dihydroisoquinolin-2( 1 H)-yl)-3-hydroxypropan- 1 -one hydrochloride

Compound-82 : (3R)-3-amino-4-(6-bromo-3,4-dihydroisoquinolin-2( 1 H)-yl)-4-oxobutanoic acid trifluoroacetate

Compound-83 :

2-amino- 1 -(6-bromo-3 ,4-dihydroisoquinolin-2( 1 H)-yl)-3 -(pyridin-2-yl)propan- 1 -one 2 hydrochloride 2 hydrochloride

Compound- 84 : 3 -amino-N- { 6- [4-(3 -hydroxypropy l)phenyl] - 1 H-indol-3 -yl } -D-alaninamide

Compound-85 : N-[6-(2-phenylethyl)-lH-indol-3-yl]-D-serinamide

Compound-86 : N-(6-bromo-lH-indol-3-yl)-D-serinamide

Compound-87 : N-(6-benzyl-l H-indol-3 -yl)-D-serinamide

Compound-88 : 3-{4-[3-(D-serylamino)-lH-indol-6-yl]phenyl}propanoic acid

Compound-89 : N-[3-(trifluoromethoxy)phenyl]-D-serinamide

Compound-90 : 3-(l-phenyl-lH-l,2,3-triazol-4-yl)-N-[3- (trifluoromethoxy)phenyljalaninamide hydrochloride

Compound-91 : N-[3-(trifluoromethoxy)phenyl]-D-threoninamide

Compound-92 : N-[3-(trifluoromethoxy)phenyl]-D-allothreoninamide

Compound-93 : 3-(2H-tetrazol-5-yl)-N-[3-(trifluoromethoxy)phenyl]-D-alanin amide hydrochloride

Compound-94 : 3-pyridin-2-yl-N-[3-(trifluoromethoxy)phenyl]-D-alaninamide 2 hydrochloride

Compound-95 : 3-(l,3-thiazol-4-yl)-N-[3-(trifluoromethoxy)phenyl]-D-alanin amide hydrochloride

Compound-96 : 3 -amino-N- [3 -(trifluoromethoxy)phenyl] -D-alaninamide 2 hydrochloride Compound-97 : N-{3-[(naphthalen-2-yl)oxy]phenyl}-D-serinamide

Compound-98 : N-{3-[([l,r-biphenyl]-4-yl)oxy]phenyl}-D-serinamide

Compound-99 : N-{3-[4-(phenylethynyl)phenoxy]phenyl}-D-serinamide Compound-100 : N-(3-phenoxyphenyl)-D-serinamide trifluoroacetate

Compound- 101 : (R)-3-amino-4-oxo-4-((3-phenoxyphenyl)amino)butanoic acid

Compound-102 : N-(3-phenoxyphenyl)-3-(l,3-thiazol-4-yl)-D-alaninamide hydrochloride Compound- 103 : N- { 3 - [4-(2-phenylethyl)phenoxy]phenyl } -D-serinamide

Compound-104 : N-{3-[([l,l'-biphenyl]-3-yl)oxy]phenyl}-D-serinamide

Test examples

The following pharmacological tests were conducted to verify the action of inventive compounds.

Test 1: Evaluation of the inhibitory activities on Pseudomonas aeruginosa LpxC enzyme Inhibitory activities on P. aeruginosa LpxC enzyme of compounds were evaluated using the following LCMS method.

(LC/MS method)

To assay the activity of P. aeruginosa LpxC enzyme, LpxC was reacted with its substrate UDP-3-0-(R-3-hydroxydecanoyl)-N-acetylglucosamine. The amounts of substrate and reacted product were determined with a liquid chromatography-tandem mass spectrometry (LC/MS/MS). Specifically, 3.6 nmol/L of P. aeruginosa LpxC enzyme (as acquired by preparing chromosomal DNA from P. aeruginosa, subjecting the DNA to PCR (polymerase chain reaction) using LpxC specific primers to acquire P. aeruginosa LpxC genes, incorporating the genes into a vector, and expressing in Escherichia coli) was mixed with 20 μπιοΙ/L of UDP-3-0-(R-3 -hydroxy decanoyl)-N-acetylglucosamine (Alberta Research Council) and the mixture was incubated at room temperature for 60 minutes. The reaction was performed in 40 mmol/L of Hepes buffer solution (pH 8.0) supplemented with 0.02% (v/v) Brij 35 and 25 nmol/L of ZnCl ₂ . To terminate the reaction, acetonitrile containing 25 μηιοΙ/L of UDP-GlcNAc as internal standard was added. The mixture was centrifuged and supernatant was injected into LC/MS/MS. The samples were separated with Inertsil Amide (3.0 μπι, 50 mm x 2.1 mm I.D., GLScience, Japan). The mobile phase was 8 mmol/L ammonium acetate containing 72% acetonitrile and flow rate was 0.2mL/min. MS/MS detection of each component was performed using a TSQ Quantum system with electrospray interface (ThermoFisher Scientific, USA) in negative ion detection mode. An inhibition curve was constructed for each test compound by performing the aforementioned reaction at varying concentrations of the test compound. From this inhibition curve, the concentration of the test compound at which the formation of the reaction product was suppressed by 50% was determined as the IC ₅₀ of the test compound, which was an index for the inhibitory activity on P. aeruginosa LpxC enzyme.

Geometric means of IC50 values from two independent tests for various test compounds are shown in Table 4. Table 4 Inhibitory activities IC ₅₀ (μΜ) on P. aeruginosa LpxC enzyme.

Compound ICso ^' CuM) Compound IC ₅₀ (μΜ)

1 0.0060 34 0.23

2 0.018 35 0.30

3 0.022 36 0.65

4 0.023 37 0.51

5 0.026 38 0.66

6 0.028 39 0.61

7 0.034 40 0.52

8 0.038 41 0.81

9 0.054 42 0.67

10 0.068 43 0.83

11 0.077 44 1.3

12 0.10 45 1.6

13 0.15 46 3.6

14 0.22 47 5.0

15 0.061 48 3.2

16 0.070 49 1.9

17 0.088 50 3.2

18 0.14 51 4.5

19 0.14 52 5.1

20 0.19 53 4.5

21 0.25 54 4.7

22 0.27 55 7.2

23 0.32 56 8.9

24 0.052 57 15

25 0.087 58 49

26 0.13 59 16

27 0.17 60 56

28 0.27 61 71

29 0.078 62 1.1

30 0.13 63 4.3

31 0.13 64 0.59

32 0.14 65 0.58

33 0.19 66 0.71 Table 4 (continued)

Industrial Applicability

The present invention enables providing novel compounds that inhibit LpxC or

pharmaceutically acceptable salts thereof, as well as new pharmaceutical drugs exhibiting antimicrobial activity against gram-negative bacteria and useful in the treatment of bacterial infections which comprise those compounds or pharmaceutically acceptable salts thereof.