FIELD OF THE INVENTION

The present invention relates to compounds of Formula (I), and in particular Formulae (II) and (III), which are inhibitors of c-ABL. The invention also relates to pharmaceutical compositions comprising those compounds, and to their use in the treatment or prevention of medical conditions in which inhibition of c-ABL is beneficial. Such medical conditions include neurodegenerative diseases and cancer.

BACKGROUND

ABL1 (Abelson Murine Leukaemia Viral Oncogene Homolog 1) is a protein that exhibits tyrosine kinase enzymatic activity and is associated with various cell functions. In humans, this protein is encoded by the ABL1 gene located on chromosome 9. The version of the ABL1 gene found within the mammalian genome is denoted c-Abl.

Philadelphia chromosome is a genetic abnormality in chromosome 22 formed by the t(9,22) reciprocal chromosome translocation, resulting in a fusion gene denoted BCR-ABL1 . This fusion gene contains the ABL1 gene from chromosome 9 and part of the BCR gene. The tyrosine kinase activity of the ABL1 protein is normally tightly regulated, however, the BCR domains in the fusion gene result in constitutive activation of the ABL1 kinase. However, the binding domains of BCR- ABL and c-ABL are identical.

Activation of c-Abl has been implicated in various diseases, notably cancer. For instance, the presence of the BCR-ABL mutation is strongly linked to chronic myeloid leukaemia (CML). It is also found in some instances of acute lymphocytic leukaemia (ALL) and acute lymphoblastic leukaemia (ALL). Nilotinib and Ponatinib are both c-Abl inhibitors that have been used in the treatment of chronic myeloid leukaemia (CML) and acute lymphocytic leukaemia (ALL). The range of leukaemias that may be treated by c-ABL inhibition include chronic myeloid leukaemia (CML), acute lymphoblastic leukaemia (ALL), acute myelogenous leukaemia (AML), mixed-phenotype acute leukaemia (MPAL), and central nervous system (CNS) metastases thereof.

Activation of c-Abl has also been implicated in neurodegenerative diseases. Neurodegenerative diseases may be characterised by progressive degeneration and ultimate death of neurons. Particular neurodegenerative diseases include amyotrophic lateral sclerosis (ALS) and Parkinson’s disease (PD).

ALS is a fatal neurodegenerative disease caused by the progressive degeneration of motor neurons. It has been reported that c-Abl signalling activation contributes to neuronal apoptosis and that c-Abl inhibitors can prevent motor neuron death [Rojas et al. Frontiers in Cellular Neuroscience, 2015, 9, 203; Imamura et al. Science Translational Medicine, 2017],

Parkinson’s disease (PD) is a progressive neurodegenerative disorder caused by a selective loss of dopaminergic neurons in the substantia nigra pars compacta. It has been reported that c-Abl is activated in the brain of patients with PD and that c-Abl inhibition can protect against dopamine neuronal loss [Pagan et al. Pharmacology Research & Perspectives, 2019; Karuppagounder et al. Scientific Reports, 2014, 4, 4874],

Activation of c-Abl has also been implicated in a wide range of other diseases including, but not limited to, prion diseases, viral infections, diabetes, inflammatory diseases such as pulmonary fibrosis, and skeletal or muscular dystrophies.

Viral infections can be mediated by ABL1 kinase activity, as in the case of poxviruses and the Ebola virus. Gleevec® and Tasigna® have been shown to stop the release of Ebola viral particles from infected cells, in vitro (see for instance WO 2007/002441 ; Mayra et al. Productive Replication of Ebola Virus Is Regulated by the ABL1 Tyrosine Kinase Science translational medicine 2012, 4, 123ra24). Inhibition of the ABL kinase can therefore be expected to reduce the pathogen's ability to replicate. In prion disease models, Gleevec® showed beneficial effects. It delayed prion neuroinvasion by inhibiting prion propagation from the periphery to the CNS (Yun et al. The tyrosine kinase inhibitor imatinib mesylate delays prion neuroinvasion by inhibiting prion propagation in the periphery J Neurovirol. 2007, 13, 328-37). Gleevec® and ABL deficiency induced cellular clearance of PrPSc in prion- infected cells (Ertmer et al. The tyrosine kinase inhibitor STI571 induces cellular clearance of PrPSc in prion-infected cells J. Biol. Chem. 2004 279, 41918-27). Therefore, ABL1 inhibitors represent a valid therapeutic approach for the treatment of prion diseases, such as Creutzfeldt-Jacob disease (CJD).

X-linked recessive Emery-Dreifuss muscular dystrophy is caused by mutations of emerin, a nuclear-membrane protein with roles in nuclear architecture, gene regulation and signalling. A study has shown that emerin is tyrosine- phosphorylated directly by ABL1 in cell models, and that the phosphorylation status of emerin changes emerin binding to other proteins such as BAF. This, in turn, may explain the mislocalization of mutant emerin from nuclear to cytosolic compartments and consequently changes in downstream effector and signal integrator for signalling pathway(s) at the nuclear envelope (Tifft et al. Tyrosine phosphorylation of nuclear- membrane protein emerin by SRC, ABL1 and other kinases J. Cell Sci. 2009, 122, 3780-90). Changes in emerin-lamin interactions during both mitosis and interphase are of relevance for the pathology of muscular dystrophies. In addition, results from another study demonstrate that Gleevec® attenuates skeletal muscle dystrophy in mdx mice (Huang et al. Imatinib attenuates skeletal muscle dystrophy in mdx mice FASEB J. 2009, 23, 2539-48). Therefore, ABL1 inhibitors also represent therapeutic approaches for treatment of skeletal and muscular dystrophies.

Furthermore, ABL1 kinase plays a role in inflammation and oxidative stress, two mechanisms that are implicated in a variety of human diseases ranging from acute CNS diseases, such as stroke and traumatic brain or spinal cord injuries, chronic CNS diseases, such as Alzheimer's, Parkinson's, Huntington's and motoneuron diseases, to non-CNS inflammatory and autoimmune diseases, such as diabetes, pulmonary fibrosis. For example, Gleevec® prevents fibrosis in different preclinical models of systemic sclerosis and induces regression of established fibrosis (Akhmetshina et al. Treatment with imatinib prevents fibrosis in different preclinical models of systemic sclerosis and induces regression of established fibrosis Arthritis Rheum. 2009, 60, 219-24) and it shows antifibrotic effects in bleomycin-induced pulmonary fibrosis in mice (Aono et al. Imatinib as a novel antifibrotic agent in bleomycin- induced pulmonary fibrosis in mice Am. J. Respir. Grit. Care Med. 2005, 171 , 1279-85). Another study showed that both imatinib and nilotinib attenuated bleomycin-induced acute lung injury and pulmonary fibrosis in mice (Rhee et al. Effect of nilotinib on bleomycin-induced acute lung injury and pulmonary fibrosis in mice. Respiration 2011 , 82, 273-87). Although in these studies the authors were focusing on the implication the mechanism related to PDGFRs, of interest, in the study by Rhee et al. (Respiration. 2011 , 82, 273-87), nilotinib which is a more potent c-ABL inhibitor than imatinib showed superior therapeutic antifibrotic effects, thus supporting the therapeutic applicability of c-ABL inhibitors for treatment of human diseases with pulmonary inflammation. In another study, exposure of mice to hyperoxia increased ABL1 activation which is required for dynamin 2 phosphorylation and reactive oxygen species production and pulmonary leak (Singleton et al. Dynamin 2 and c-Abl are novel regulators of hyperoxia-mediated NADPH oxidase activation and reactive oxygen species production in caveolin-enriched microdomains of the endothelium J. Biol. Chem. 2009, 284, 34964-75).

In view of the above there is an unmet need for new compounds that may be used in the treatment and prevention of medical conditions in which inhibition of c-ABL is beneficial, such as neurodegenerative diseases (i.e. ALS and PD) and cancer (especially leukaemias).

DISCLOSURE OF THE INVENTION

Surprisingly, it has been found that compounds of Formula (I) may inhibit c-ABL and therefore treat or prevent the above medical conditions. Further, they have certain beneficial properties leading to increased potential for use as a drug compared to known compounds. This may be in terms of their efficacy, efflux profile (P-pg and/or BCRP), free brain level at C _m ax, solubility, selectivity profiles, such as kinase selectivity, low hERG inhibitory activity, safety profile, and/or other notable pharmacokinetic properties.

Consequently, the first aspect of the invention relates to a compound of Formula

(I), or a pharmaceutically acceptable salt, solvate, hydrate, tautomer, optical isomer, N-oxide, and/or prodrug thereof, wherein

Het is an optionally substituted 5- or 6-membered monocyclic heteroaryl or an optionally substituted 8- to 10-membered bicyclic heteroaryl;

Each Y is C or N, wherein one Y is C and one Y is N;

Z is C or O; n is 0, 1 , 2, 3, 4, 5, or 6, preferably 0, 1 , 2, or 3;

R ¹ is selected from the group consisting of H, halo, and C1-C3 alkyl, wherein the C1-C3 alkyl is optionally substituted with one or more halo atoms; and each R ² is independently selected from the group consisting of halo, and C1-C3 alkyl, wherein the C1-C3 alkyl is optionally substituted with one or more halo atoms; with the proviso that Het is not unsubstituted pyridyl.

These compounds are compounds of the invention. Without wishing to be bound by theory, the surprising beneficial properties of the compounds of the invention may be attributed, in part, to the partially saturated fused bicyclic ring system attached to the amide group in the compounds of Formula (I), particularly when combined with the optionally substituted 5- or 6- membered monocyclic heteroaryl or optionally substituted 8- to 10-membered bicyclic heteroaryl of group Het. It has been unexpectedly found that compounds that comprise the partially saturated fused bicyclic ring have high BAF3/ABL inhibitory activity (indicated by low IC50 values) and low P-gp efflux and BCRP efflux, making them particularly useful in the treatment of certain diseases and conditions. It is noted that P-gp/BCRP efflux is unpredictable and must be established empirically. Overcoming the challenges associated with delivering therapeutic agents with low susceptibility to efflux presents a major challenge to treatment of many disorders, particularly disorders affecting the brain.

P-glycoprotein 1 (P-gp) also known as multidrug resistance protein 1 (MDR1) or ATP-binding cassette sub-family B member 1 (ABCB1) or cluster of differentiation 243 (CD243) is an important protein of the cell membrane that pumps many foreign substances out of cells. It is an ATP-dependent efflux pump with broad substrate specificity, and is likely evolved as a defence mechanism against harmful substances. P-gp is extensively distributed and expressed in the capillary endothelial cells composing the blood-brain barrier (as well as the blood-testis barrier) where it pumps xenobiotics (such as toxins or drugs) back into the capillaries. It is also present in the intestinal epithelium where it pumps xenobiotics back into the intestinal lumen, in liver cells where it pumps them into bile ducts, and in the cells of the proximal tubule of the kidney where it pumps them into urinary filtrate (in the proximal tubule).

Breast cancer resistance protein (BCRP), also known as ATP-binding cassette super-family G member 2 (ABCG2). It is a membrane-associated protein that transports various molecules across extra- and intra-cellular membranes, and has been shown to play protective roles in blocking absorption at the blood-brain barrier as well as the apical membrane of the intestine, the blood-testis barrier, and the membranes of hematopoietic progenitor and other stem cells. In cases where the drug target is located within the central nervous system, it is usually preferable that compounds are not substrates for these efflux transporters in order to prevent restriction to the periphery with limited CNS exposure.

As used herein, the term “unsubstituted pyridyl” means a monovalent radical of pyridine with only hydrogen atoms attached to the ring except for the point at which it is attached to the remainder of the compound. Therefore, in compounds of the invention, Het is not one of the following unsubstituted groups:

Other than unsubstiuted pyridyl, Het may be any suitable optionally substituted 5- or 6-membered monocyclic heteroaryl or optionally substituted 8- to 10- membered bicyclic heteroaryl. As used herein “5- or 6-membered monocylic heteroaryl” is an aromatic monocyclic hydrocarbon ring in which at least one, such as 1 , 2, 3, or 4, ring atom is a heteroatom. As used herein “8- to 10-membered bicyclic heteroaryl” is a heteroaromatic fused bicyclic ring system in which at least one, such as 1 , 2, 3, or 4, ring atom is a heteroatom.

In a preferred feature of the invention, Het is an optionally substituted 5- or 6- membered monocyclic heteroaryl or an optionally substituted 9- or 10-membered bicyclic heteroaryl.

In a more preferred feature of the invention, Het is selected from the group consisting of optionally substituted pyrrolyl, pyrazolyl, imidazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, oxadiazolyl, thiadiazolyl, pyridyl, pyrimidinyl, pyrazinyl, triazinyl, indolyl, isoindolyl, indolizinyl, indazolyl, benzimidazolyl, pyrrolopyridinyl, azaindazolyl, pyrazolopyrimidinyl, purinyl, benzofuranyl, isobenzofuranyl, benzothiophenyl, benzoisoxazolyl, benzoisothiazolyl, benzoxazolyl, benzothiazolyl, furopyridinyl, quinolinyl, isoquinolinyl, quinoxalinyl, phthalazinyl, cinnolinyl, naphthyridinyl, pyridopyrimidinyl, pyridopyrazinyl, and pteridinyl. More preferably it is selected from optionally substituted pyrrolyl, pyrazolyl, imidazolyl, triazolyl, pyridyl, pyrimidinyl, pyrazinyl, triazinyl, pyrrolopyridinyl, furopyridinyl, and naphthyridinyl. Most preferably it is selected from optionally substituted imidazolyl, pyridyl, pyrimidinyl, napthyridinyl, and furopyridinyl.

Preferable examples of 5- or 6-membered heteroaryls for group Het may be in the following regioisomeric forms or a tautomer thereof, with each group being optionally substituted, including substitution of the H attached to a N atom. More preferably they may be the following regioisomeric forms or a tautomer thereof, with each group being optionally substituted, including substitution of the H attached to a N atom.

Preferable examples of 8- or 10-membered heteroaryls for group Het, an the preferable 9- or 10-membered heteroaryls, may be in the following regioisomeric forms with each group being optionally substituted, including substitution of the H attached to a N atom. More preferably they may be the following regioisomeric forms with each group being optionally substituted.

In a highly preferred feature of the invention, Het is selected from one of the following groups: each of which being optionally substituted, including substitution of the H attached to a N atom.

Het may be substituted with one or more substituents, as mentioned above. However, it is preferred that the substitution is one or more of the groups selected from the group consisting of

(i) Ci-Ce alkyl, C2-C6 alkenyl, C2-C6 alkynyl, and Ci-Ce alkoxy, each of which is optionally substituted with one or more substituents independently selected from -OR ³ , -NR ⁴ R ⁵ , halo, and oxo;

(ii) halo, -ON, -C(O)NR ⁴ R ⁵ , -NR ⁴ R ⁵ , -C(O)OR ³ , -C(O)R ³ , and -OR ³ ; and

(iii) Ce-Cio aryl, C1-C9 heteroaryl, and C1-C9 heterocycle, each of which is optionally substituted with one or more substituents independently selected from halo and Ci-Ce alkyl, wherein the Ci-Ce alkyl is optionally substituted with one or more halo atoms. Each R ³ , R ⁴ , and R ⁵ is independently selected from the group consisting of H and C1-C3 alkyl, wherein the C1-C3 alkyl is optionally substituted with one or more halo atoms.

More preferred optional substituents for Het are selected from the group consisting of:

(i) C1-C3 alkyl and C1-C3 alkoxy, each of which is optionally substituted with one or more substituents independently selected from halo, oxo, -OR ³ , and -NR ⁴ R ⁵ ;

(ii) halo, -ON, -C(O)NR ⁴ R ⁵ , -NR ⁴ R ⁵ , -C(O)OR ³ , -C(O)R ³ , and -OR ³ ; and

(iii) 4- to 7-membered heterocycle and 5- or 6-membered monocyclic heteroaryl, each of which is independently optionally substituted with one or more substituents independently selected from halo, C1-C3 alkyl, and -NR ⁴ R ⁵ , wherein the Ci-Ce alkyl is optionally substituted with one or more halo atoms.

Most preferred optional substituents for Het are selected from the group consisting of:

(i) C1-C3 alkyl, optionally substituted with one or more halo atoms;

(ii) halo, -OR ³ , -NR ⁴ R ⁵ , -C(O)NR ⁴ R ⁵ ; and

(iii) 4- to 7-membered heterocycle and 5-membered monocyclic heteroaryl, each of which is independently optionally substituted with one or more substituents independently selected from halo, C1-C3 alkyl and -NR ⁴ R ⁵ , wherein the C1-C3 alkyl is optionally substituted with one or more halo atoms.

As used herein, the term “4- to 7-membered heterocycle” is a non-aromatic monocyclic ring system having 4 to 7 ring atoms, in which at least one ring atom is a heteroatom. Preferrable examples of 4- to 7-membered heterocycles include azetidinyl, pyrrolidinyl, pyrazolidinyl, imidazolidinyl, piperidinyl, and piperazinyl, more preferably azetidinyl and pyrrolidinyl, each of which are optionally substituted as described above. Most preferably, the 4- to 7-memebered heterocycle is one of the following groups, each of which are optionally substited as described above:

Preferreable examples of the 5-membered monocyclic heteroaryl as a substituent on Het include pyrrolyl, pyrazolyl, imidazolyl, triazolyl, and tetrazolyl, more preferably pyrazolyl and triazole, each of which are optionally substituted as described above. Most preferably, the 5-membered monocyclic heteroaryl is one of the following groups, each of which are optionally substituted as described above:

Without wishing to be bound by theory, it may be particularly advantageous to include a substitutent on the Het group which can act as a hydrogen bond donor, as this may increase interaction with c-Abl, thereby increasing binding affinity and inhibition of c-Abl. When Het is a 6-membered heteroaryl group, it is most preferable that the hydrogen-bonding substituent is located at the 4-position relative to the point of attachment to the remainder of the compound. When Het is a 5-memebered heteroaryl group, it is most preferable that the hydrogenbonding substituent is located at the 3-position relative to the point of attachment to the remainder of the compound. Therefore, in a particularly preferred feature of the invention, Het is selected from one of the following groups: each of which being optionally substituted, wherein each R ⁶ is independently selected from the group consisting of -NHR ⁴ and -C(O)NHR ⁴ . Z is C or O. It will be understood that when Z is C, it will be attached to two H, each of which may be independently substituted with R ² in accordance with the definion of n.

In one preferred aspect of the invention, the compound of Formula (I) is a compound of Formula (II) or a pharmaceutically acceptable salt, solvate, hydrate, tautomer, optical isomer, N-oxide, and/or prodrug thereof, wherein each X is independently halo, preferably F;

R ¹ is H or C1-C3 alkyl, preferably H, ethyl, or cyclopropyl, most preferably H; and Het is as defined above for Formula (I).

In preferred compounds of Formula (II), Het is selected from one of the following groups: each of which is optionally substituted with one or more substituents independently selected from the group consisting of

(i) C1-C3 alkyl, optionally substituted with one or more halo atoms;

(ii) halo, -OR ³ , -NR ⁴ R ⁵ , -C(O)NR ⁴ R ⁵ ; and

(iii) 4- to 7-membered heterocycle and 5-membered monocyclic heteroaryl, each of which is independently optionally substituted with one or more substituents independently selected from halo, C1-C3 alkyl and -NR ⁴ R ⁵ , wherein the C1-C3 alkyl is optionally substituted with one or more halo atoms, preferably wherein the 4- to 7-membered heterocycle is monocyclic.

In another preferred aspect of the invention, the compound of Formula (I) is a compound of Formula (III) or a pharmaceutically acceptable salt, solvate, hydrate, tautomer, optical isomer, N-oxide, and/or prodrug thereof, wherein Het is as defined above for Formula (I).

In preferred compounds of Formula (III), Het is selected from one of the following groups: each of which is optionally substituted with one or more substituents independently selected from the group consisting of

(i) C1-C3 alkyl, optionally substituted with one or more halo atoms;

(ii) halo, -OR ³ , -NR ⁴ R ⁵ , -C(O)NR ⁴ R ⁵ ; and

(iii) 4- to 7-membered heterocycle and 5-membered monocyclic heteroaryl, each of which is independently optionally substituted with one or more substituents independently selected from halo, C1-C3 alkyl and -NR ⁴ R ⁵ , wherein the C1-C3 alkyl is optionally substituted with one or more halo atoms, preferably wherein the 4- to 7-membered heterocycle is monocyclic. In more preferred compounds of Formula (II), Het is selected from one of the following groups:

X j and - XXX^i , each of which is optionally substited with one or more substituents independently selected from the group consisting of:

(i) C1-C3 alkyl, optionally substituted with one or more halo atoms; and

(ii) halo, -OR ³ , -NR ⁴ R ⁵ , -C(O)NR ⁴ R ⁵ .

Specific compounds of the invention include

• 3-[2-(2-aminopyrimidin-5-yl)ethynyl]-N-(4,4-difluoro-6,7-dih ydro-5H- pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-benzamide;

• 5-[2-[5-[(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)carbamoyl]-2- methyl-phenyl]ethynyl]-N,1-dimethyl-imidazole-2-carboxamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-(2- pyrimidin-5-ylethynyl)benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-[5- (triazol-2-yl)-3-pyridyl]ethynyl]benzamide;

• 3-[2-(6-amino-3-pyridyl)ethynyl]-N-(4,4-difluoro-6,7-dihydro -5H-pyrazolo[1 ,5- a]pyridin-2-yl)-4-methyl-benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-[2- (methylamino)pyrimidin-5-yl]ethynyl]benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-[6- (methylamino)-3-pyridyl]ethynyl]benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-[2-[6- (difluoromethyl)-3-pyridyl]ethynyl]-4-methyl-benzamide;

• 5-[2-[5-[(3-Ethyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2- yl)carbamoyl]-2-methyl-phenyl]ethynyl]-N,1-dimethyl-imidazol e-2- carboxamide; • N-(3-ethyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl- 3-[2-[2-(methylamino)pyrimidin-5-yl]ethynyl]benzamide;

• N-(3-cyclopropyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4- methyl-3-[2-[2-(methylamino)pyrimidin-5-yl]ethynyl]benzamide ;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-(5- pyrazol-1-yl-3-pyridyl)ethynyl]benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-[2-(5-fluoro-3- pyridyl)ethynyl]-4-methyl-benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-(2-furo[3,2- b]pyridin-6-ylethynyl)-4-methyl-benzamide;

• 3-[2-(2-amino-3-pyridyl)ethynyl]-N-(4,4-difluoro-6,7-dihydro -5H-pyrazolo[1 ,5- a]pyridin-2-yl)-4-methyl-benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-(1 ,6- naphthyridin-3-yl)ethynyl]benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-[2-(4- methoxypyrimidin-5-yl)ethynyl]-4-methyl-benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-[2-(5-methoxy-3- pyridyl)ethynyl]-4-methyl-benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-(5- methyl-3-pyridyl)ethynyl]benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-[2-[5-[3- (dimethylamino)pyrrolidin-1-yl]-3-pyridyl]ethynyl]-4-methyl- benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-[2-[5-(2- ethylazetidin-1-yl)-3-pyridyl]ethynyl]-4-methyl-benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-[5- (2-methylazetidin-1-yl)-3-pyridyl]ethynyl]benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-[5- (1-methylpyrrolidin-3-yl)-3-pyridyl]ethynyl]benzamide;

• N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-[5- [2-(trifluoromethyl)azetidin-1-yl]-3-pyridyl]ethynyl]benzami de; and

• N-(5,5-Dimethyl-6,8-dihydroimidazo[2,1-c][1 ,4]oxazin-2-yl)-4-methyl-3-[2-[6- (methylamino)-3-pyridyl]ethynyl]benzamide; or a pharmaceutically acceptable salt, solvate, hydrate, tautomer, optical isomer, N-oxide, and/or prodrug thereof.

The compounds of the invention may include isotopically-labelled and/or isotopically-enriched forms of the compounds. The compounds of the invention herein may contain unnatural proportions of atomic isotopes at one or more of the atoms that constitute such compounds. Examples of isotopes that can be incorporated into the disclosed compounds include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, chlorine, such as ² H, ³ H, ¹¹ C, ¹³ C, ¹⁴ C, ¹³ N,

The compounds of the invention may be used as such or, where appropriate, as pharmacologically acceptable salts (acid or base addition salts) thereof. The pharmacologically acceptable addition salts mentioned below are meant to comprise the therapeutically active non-toxic acid and base addition salt forms that the compounds are able to form. Compounds that have basic properties can be converted to their pharmaceutically acceptable acid addition salts by treating the base form with an appropriate acid. Exemplary acids include inorganic acids, such as hydrogen chloride, hydrogen bromide, hydrogen iodide, sulphuric acid, phosphoric acid; and organic acids such as formic acid, acetic acid, propanoic acid, hydroxyacetic acid, lactic acid, pyruvic acid, glycolic acid, maleic acid, malonic acid, oxalic acid, benzenesulphonic acid, toluenesulphonic acid, methanesulphonic acid, trifluoroacetic acid, fumaric acid, succinic acid, malic acid, tartaric acid, citric acid, salicylic acid, p-aminosalicylic acid, pamoic acid, benzoic acid, ascorbic acid and the like. Exemplary base addition salt forms are the sodium, potassium, calcium salts, and salts with pharmaceutically acceptable amines such as, for example, ammonia, alkylamines, benzathine, and amino acids, such as, e.g. arginine and lysine. The term addition salt as used herein also comprises solvates which the compounds and salts thereof are able to form, such as, for example, hydrates, alcoholates and the like.

Throughout the present disclosure, a given chemical formula or name shall also encompass all pharmaceutically acceptable salts, solvates, hydrates, N-oxides, and/or prodrug forms thereof. It is to be understood that the compounds of the invention include any and all hydrates and/or solvates of the compound formulas. It is appreciated that certain functional groups, such as the hydroxy, amino, and like groups form complexes and/or coordination compounds with water and/or various solvents, in the various physical forms of the compounds. Accordingly, the above formulas are to be understood to include and represent those various hydrates and/or solvates.

Compounds of the invention also include tautomeric forms. Tautomeric forms result from the swapping of a single bond with an adjacent double bond together with the concomitant migration of a proton. Tautomeric forms include prototropic tautomers which are isomeric protonation states having the same empirical formula and total charge. Example prototropic tautomers include ketone - enol pairs, amide - imidic acid pairs, lactam - lactim pairs, amide - imidic acid pairs, enamine - imine pairs, and annular forms where a proton can occupy two or more positions of a heterocyclic system, for example, 1 H- and 3H-imidazole, 1 H, 2H- and 4H- 1 ,2,4-triazole, 1 H- and 2H- isoindole, and 1 H- and 2H-pyrazole. Tautomeric forms can be in equilibrium or sterically locked into one form by appropriate substitution.

The compounds described herein can be asymmetric (e.g. having one or more stereocenters). All stereoisomers, such as enantiomers and diastereomers, are intended unless otherwise indicated. Compounds of the present invention that contain asymmetrically substituted carbon atoms can be isolated in optically active or racemic forms. Methods on how to prepare optically active forms from optically active starting materials are known in the art, such as by resolution of racemic mixtures or by stereoselective synthesis. Many geometric isomers of olefins, C=N double bonds, and the like can also be present in the compounds described herein, and all such stable isomers are contemplated in the present invention. Cisand trans-geometric isomers of the compounds of the present invention are described and may be isolated as a mixture of isomers or as separated isomeric forms.

In the case of the compounds which contain an asymmetric carbon atom, the invention relates to the D form, the L form, and D,L mixtures and also, where more than one asymmetric carbon atom is present, to the diastereomeric forms. Those compounds of the invention which contain asymmetric carbon atoms, and which as a rule accrue as racemates, can be separated into the optically active isomers in a known manner, for example using an optically active acid. However, it is also possible to use an optically active starting substance from the outset, with a corresponding optically active or diastereomeric compound then being obtained as the end product.

The term "prodrugs" refers to compounds that may be converted under physiological conditions or by solvolysis to a biologically active compound of the invention. A prodrug may be inactive when administered to a subject in need thereof, but is converted in vivo to an active compound of the invention. Prodrugs are typically rapidly transformed in vivo to yield the parent compound of the invention, e.g. by hydrolysis in the blood. The prodrug compound usually offers advantages of solubility, tissue compatibility or delayed release in a mammalian organism (see Silverman, R. B., The Organic Chemistry of Drug Design and Drug Action, 2nd Ed., Elsevier Academic Press (2004), page 498 to 549). Prodrugs of a compound of the invention may be prepared by modifying functional groups, such as a hydroxy, amino or mercapto groups, present in a compound of the invention in such a way that the modifications are cleaved, either in routine manipulation or in vivo, to the parent compound of the invention. Examples of prodrugs include, but are not limited to, acetate, formate and succinate derivatives of hydroxy functional groups or phenyl carbamate derivatives of amino functional groups.

Another object of the present invention relates to the compounds of the invention for use in therapy.

The compounds of the invention are useful as inhibitors of c-ABL. As such, they are useful in the treatment or prevention of medical conditions (conditions or diseases) in which inhibition of c-ABL is beneficial. There is therefore provided a method of for the treatment or prevention of a disease or condition responsive to c-ABL inhibition comprising administering a therapeutically effective amount of a compound of the invention to a subject. Whilst the compounds of the invention may be suitable to prevent a range of diseases and conditions, it is preferable that they are used to treat said diseases and conditions. Therefore, it is preferred that the method is for the treatment of a disease or condition, and therefore the method comprises administering a therapeutically effective amount of a compound of the invention to a subject in need thereof.

The term “treatment” as used herein may include prophylaxis of the named disorder or condition, or amelioration or elimination of the disorder once it has been established. The term “prevention” refers to prophylaxis of the named disorder or condition.

The range of diseases and conditions treatable or preventable by c-ABL inhibition is well known. The compounds of the invention therefore may be used to treat or prevent this range of diseases or conditions. This includes neurodegenerative disorders, cancers, prion diseases, viral infections, diabetes, inflammatory diseases such as pulmonary fibrosis, or a skeletal or muscular dystrophy. Preferably, the disease is a neurodegenerative disorder or a cancer.

Treatable or preventable neurodegenerative disorders include, but are not limited to, Alzheimer disease, Down’s syndrome, frontotemporal dementia, progressive supranuclear palsy, Pick’s disease, Niemann-Pick disease, Parkinson’s disease, Huntington’s disease (HD), dentatorubropallidoluysian atrophy, Kennedy’s disease, and spinocerebellar ataxia, fragile X (Rett’s) syndrome, fragile XE mental retardation, Friedreich’s ataxia, myotonic dystrophy, spinocerebellar ataxia type 8, and spinocerebellar ataxia type 12, Alexander disease, Alper’s disease, amyotrophic lateral sclerosis (ALS), ataxia telangiectasia, Batten disease, Canavan disease, Cockayne syndrome, corticobasal degeneration, Creutzfeldt- Jakob disease, ischemia stroke, Krabbe disease, Lewy body dementia, multiple sclerosis, multiple system atrophy, Pelizaeus-Merzbacher disease, Pick’s disease, primary lateral sclerosis, Refsum’s disease, Sandhoff disease, Schilder’s disease, spinal cord injury, spinal muscular atrophy, Steele-Richardson-Olszewski disease, and Tabes dorsalis. Of the treatable or preventable neurodegenerative disorders, most notable are amyotrophic lateral sclerosis (ALS) and Parkinson’s disease. Most preferably the neurodegenerative disorder is ALS.

Treatable or preventable cancers include, but are not limited to, leukaemia.

Of the treatable or preventable cancers, most notable are chronic myeloid leukaemia (CML), acute lymphoblastic leukaemia (ALL), acute myelogenous leukaemia (AML), and mixed-phenotype acute leukaemia (MPAL), or any central nervous system (CNS) metastases thereof. Most preferably the cancer is CML or ALL.

The invention thus includes the use of the compounds of the invention in the manufacture of a medicament for the treatment or prevention of a disease or condition, such as the above-mentioned neurodegenerative disorders and cancers. The invention also relates to the compounds of the invention for use in the treatment of a disease or condition, such as the above-mentioned neurodegenerative disorders and cancers.

Methods delineated herein include those wherein the subject is identified as in need of a particular stated treatment. Identifying a subject in need of such treatment can be in the judgment of a subject or a health care professional and can be subjective (e.g. opinion) or objective (e.g. measurable by a test or diagnostic method).

In other aspects, the methods herein include those further comprising monitoring subject response to the treatment administrations. Such monitoring may include periodic sampling of subject tissue, fluids, specimens, cells, proteins, chemical markers, genetic materials, etc. as markers or indicators of the treatment regimen. In other methods, the subject is pre-screened or identified as in need of such treatment by assessment for a relevant marker or indicator of suitability for such treatment. The invention provides a method of monitoring treatment progress. The method includes the step of determining a level of diagnostic marker (Marker) (e.g. any target or cell type delineated herein modulated by a compound herein) or diagnostic measurement (e.g., screen, assay) in a subject suffering from or susceptible to a disorder or symptoms thereof delineated herein, in which the subject has been administered a therapeutic amount of a compound herein sufficient to treat the disease or symptoms thereof. The level of Marker determined in the method can be compared to known levels of Marker in either healthy normal controls or in other afflicted patients to establish the subject's disease status. In preferred embodiments, a second level of Marker in the subject is determined at a time point later than the determination of the first level, and the two levels are compared to monitor the course of disease or the efficacy of the therapy. In certain preferred embodiments, a pre-treatment level of Marker in the subject is determined prior to beginning treatment according to this invention; this pretreatment level of Marker can then be compared to the level of Marker in the subject after the treatment commences, to determine the efficacy of the treatment.

A level of Marker or Marker activity in a subject may be determined at least once. Comparison of Marker levels, e.g., to another measurement of Marker level obtained previously or subsequently from the same patient, another patient, or a normal subject, may be useful in determining whether therapy according to the invention is having the desired effect, and thereby permitting adjustment of dosage levels as appropriate. Determination of Marker levels may be performed using any suitable sampling/expression assay method known in the art or described herein. Preferably, a tissue or fluid sample is first removed from a subject. Examples of suitable samples include blood, urine, tissue, mouth or cheek cells, and hair samples containing roots. Other suitable samples would be known to the person skilled in the art. Determination of protein levels and/or mRNA levels (e.g., Marker levels) in the sample can be performed using any suitable technique known in the art, including, but not limited to, enzyme immunoassay, is ELISA, radiolabeling/assay techniques, blotting/chemiluminescence methods, real-time PCR, and the like. For clinical use, the compounds disclosed herein are formulated into pharmaceutical compositions (or formulations) for various modes of administration. It will be appreciated that compounds of the invention may be administered together with a physiologically acceptable carrier, excipient, and/or diluent (i.e. one, two, or all three of these). The pharmaceutical compositions disclosed herein may be administered by any suitable route, preferably by oral, rectal, nasal, topical (including buccal and sublingual), sublingual, transdermal, intrathecal, transmucosal or parenteral (including subcutaneous, intramuscular, intravenous and intradermal) administration. Other formulations may conveniently be presented in unit dosage form, e.g., tablets and sustained release capsules, and in liposomes, and may be prepared by any methods well known in the art of pharmacy. Pharmaceutical formulations are usually prepared by mixing the active substance, or a pharmaceutically acceptable salt thereof, with conventional pharmaceutically acceptable carriers, diluents or excipients. Examples of excipients are water, gelatin, gum arabicum, lactose, microcrystalline cellulose, starch, sodium starch glycolate, calcium hydrogen phosphate, magnesium stearate, talcum, colloidal silicon dioxide, and the like. Such formulations may also contain other pharmacologically active agents, and conventional additives, such as stabilizers, wetting agents, emulsifiers, flavouring agents, buffers, and the like. Usually, the amount of active compounds is between 0.1-95% by weight of the preparation, preferably between 0.2-20% by weight in preparations for parenteral use and more preferably between 1-50% by weight in preparations for oral administration. The formulations can be further prepared by known methods such as granulation, compression, microencapsulation, spray coating, etc. The formulations may be prepared by conventional methods in the dosage form of tablets, capsules, granules, powders, syrups, suspensions, suppositories or injections. Liquid formulations may be prepared by dissolving or suspending the active substance in water or other suitable vehicles. Tablets and granules may be coated in a conventional manner. To maintain therapeutically effective plasma concentrations for extended periods of time, compounds disclosed herein may be incorporated into slow release formulations.

The dose level and frequency of dosage of the specific compound will vary depending on a variety of factors including the potency of the specific compound employed, the metabolic stability and length of action of that compound, the patient's age, body weight, general health, sex, diet, mode and time of administration, rate of excretion, drug combination, the severity of the condition to be treated, and the patient undergoing therapy. The daily dosage may, for example, range from about 0.001 mg to about 100 mg per kilo of body weight, administered singly or multiply in doses, e.g. from about 0.01 mg to about 25 mg each. Normally, such a dosage is given orally but parenteral administration may also be chosen.

DEFINITIONS

The term “substituted” means that the group to which it refers has one or more hydrogen atoms substituted for a different group. For instance, “substituted pyrazolyl” refers to a monovalent radical of pyrazole with one or more hydrogens attached to the ring being repaced with another group.

The term “heteroatom” means O, N, or S. Typically, it is preferred that the heteroatom or heteroatoms in the 5- or 6-membered heteroaryl group is nitrogen.

“Optional” or “optionally” means that the subsequently described event or circumstance may, but need not, occur, and that the description includes instances where the event or circumstance occurs and instances in which it does not.

The term “Ci-Ce alkyl” denotes a straight, branched or cyclic or partially cyclic alkyl group having from 1 to 6 carbon atoms, i.e. 1 , 2, 3, 4, 5 or 6 carbon atoms. For the “Ci-Ce alkyl” group to comprise a cyclic portion it should be formed of 3 to 6 carbon atoms. For parts of the range “Ci-Ce alkyl” all subgroups thereof are contemplated, such as C1-C5 alkyl, C1-C4 alkyl, C1-C3 alkyl, C1-C2 alkyl, Ci alkyl, C2-C6 alkyl, C2-C5 alkyl, C2-C4 alkyl, C2-C3 alkyl, C2 alkyl, C3-C6 alkyl, C3-C5 alkyl, C3-C4 alkyl, C3 alkyl, C4-C6 alkyl, C4-C5 alkyl, C4 alkyl, Cs-Ce alkyl, C5 alkyl, and Ce alkyl. Examples of “Ci-Ce alkyl” include methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, cyclobutyl, cyclopropylmethyl, and straight, branched or cyclic or partially cyclic pentyl and hexyl etc. When a term denotes a range, for instance “1 to 6 carbon atoms” in the definition of Ci-C ₆ alkyl, each integer is considered to be disclosed, i.e. 1 , 2, 3, 4, 5 and 6.

The term “C2-C6 alkenyl” denotes a straight, branched or cyclic or partially cyclic alkyl group having at least one carbon-carbon double bond, and having from 2 to 6 carbon atoms. The alkenyl group may comprise a ring formed of 3 to 6 carbon atoms. For parts of the range “C2-C6 alkenyl” all subgroups thereof are contemplated, such as C2-C5 alkenyl, C2-C4 alkenyl, C2-C3 alkenyl, C2 alkenyl, Cs- Ce alkenyl, C3-C5 alkenyl, C3-C4 alkenyl, C3 alkenyl, C4-C6 alkenyl, C4-C5 alkenyl, C4 alkenyl, Cs-Ce alkenyl, C5 alkenyl, and Ce alkenyl. Examples of “C2-C6 alkenyl” include 2-propenyl, 2-butenyl, 3-butenyl, 2-methyl-2-propenyl, 2-hexenyl, 5- hexenyl, 2,3-dimethyl-2-butenyl.

The term “C2-C6 alkynyl” denotes a straight, branched or cyclic or partially cyclic alkyl group having at least one carbon-carbon triple bond, and having from 2 to 6 carbon atoms. The alkynyl group may comprise a ring formed of 3 to 6 carbon atoms. For parts of the range “C2-C6 alkynyl” all subgroups thereof are contemplated, such as C2-C5 alkynyl, C2-C4 alkynyl, C2-C3 alkynyl, C2 alkynyl, Cs- Ce alkynyl, C3-C5 alkynyl, C3-C4 alkynyl, C3 alkynyl, C4-C6 alkynyl, C4-C5 alkynyl, C4 alkynyl, Cs-Ce alkynyl, C5 alkynyl, and Ce alkynyl. Examples of “C2-C6 alkynyl” include 2-propynyl, 2-butynyl, 3-butynyl, 2-pentynyl, 3-methyl-4-pentynyl, 2- hexynyl, 5-hexynyl etc.

The term “Ci-Ce alkoxy” denotes -O-(Ci-Cealkyl) in which a Ci-Ce alkyl group is as defined above and is attached to the remainder of the compound through an oxygen atom. Examples of “Ci-Ce alkoxy” include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, t-butoxy and straight- and branched- chain pentoxy and hexoxy.

The term “halo” means a halogen atom, and is preferably, F, Cl, Br and I, more preferably F and Cl, and most preferably F. The term “oxo” denotes a double bond to an oxygen atom (=O). This typically forms a ketone or aldehyde group.

The term “Ce-C aryl” denotes an aromatic monocyclic or fused bicyclic hydrocarbon ring comprising 6 to 10 ring atoms. Examples of “Ce-Cw aryl” groups include phenyl, indenyl, naphthyl, and naphthalene.

The term “C1-C9 heteroaryl” denotes an aromatic monocyclic or fused bicyclic heteroaromatic ring system having 5 to 10 ring atoms in which 1 to 9 of the ring atoms are carbon and one or more of the ring atoms are selected from nitrogen, sulphur, and oxygen. Examples of “C1-C9 heteroaryl” include furyl, pyrrolyl, thienyl, oxazolyl, isoxazolyl, imidazolyl, thiazolyl, isothiazolyl, pyridinyl, pyrimidinyl, tetrazolyl, quinazolinyl, indolyl, indolinyl, isoindolyl, isoindolinyl, pyrazolyl, pyridazinyl, pyrazinyl, quinolinyl, quinoxalinyl, thiadiazolyl, benzofuranyl, 2,3-dihydrobenzofuranyl, 1 ,3-benzodioxolyl, 1 ,4-benzodioxinyl, 2,3- dihydro-1 ,4-benzodioxinyl, benzothiazolyl, benzimidazolyl, benzothiadiazolyl, benzotriazolyl and chromanyl.

The term “C1-C9 heterocycle” denotes a non-aromatic monocyclic or fused bicyclic ring system having 5 to 10 ring atoms containing 1 to 9 carbon atoms and one or more of the ring atoms are selected from nitrogen, sulphur, and oxygen. When present, the sulfur atom may be in an oxidized form (i.e. the diradicle of S=O or the diradical of O=S=O). The ring system may be fully saturated or partially unsaturated. Examples of “C1-C9 heterocycle” include piperidinyl, tetrahydropyranyl, tetrahydrofuranyl, oxetanyl, azepinyl, azetidinyl, pyrrolidinyl, morpholinyl, imidazolinyl, imidazolidinyl, thiomorpholinyl, pyranyl, dioxanyl, piperazinyl, homopiperazinyl, and 5,6-dihydro-4H-1 ,3-oxazin-2-yl.

“An effective amount” refers to an amount of a compound of the invention that confers a therapeutic effect on the treated subject. The therapeutic effect may be objective (i.e. measurable by some test or marker) or subjective (i.e. subject gives an indication of or feels an effect). As used herein, the terms “administration” or “administering” mean a route of administration for a compound disclosed herein. Exemplary routes of administration include, but are not limited to, oral, intravenous, intraperitoneal, intraarterial, and intramuscular. The preferred route of administration can vary depending on various factors, e.g. the components of the pharmaceutical composition comprising a compound disclosed herein, site of the potential or actual disease and severity of disease.

The terms "subject" and "patient" are used herein interchangeably. They refer to a human or another mammal (e.g., mouse, rat, rabbit, dog, cat, cattle, swine, sheep, horse or primate) that can be afflicted with or is susceptible to a disease or disorder but may or may not have the disease or disorder. It is preferred that the subject is human.

Compounds of the invention may be disclosed by the name or chemical structure. If a discrepancy exists between the name of a compound and its associated chemical structure, then the chemical structure prevails.

The invention will now be further illustrated by the following non-limiting examples. The specific examples below are to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever. Without further elaboration, it is believed that one skilled in the art can, based on the description herein, utilise the present invention to its fullest extent. All references and publications cited herein are hereby incorporated by reference in their entirety.

PREPARATION OF COMPOUNDS OF THE INVENTION

The compounds of formula (I) disclosed herein may be prepared by, or in analogy with, conventional methods. Appropriate reaction conditions for the individual reaction steps are known to a person skilled in the art. The necessary starting materials for preparing the compounds of formula (I) are either commercially available, or may be prepared by methods known in the art. The compounds of formula (I) may possess one or more chiral carbon atoms, and they may therefore be obtained in the form of optical isomers, e.g., as a pure enantiomer, or as a mixture of enantiomers (racemate) or as a mixture containing diastereomers. The separation of mixtures of optical isomers to obtain pure enantiomers is well known in the art and may, for example, be achieved by fractional crystallization of salts with optically active (chiral) acids or by chromatographic separation on chiral columns.

Particular experimental procedures for examples of the invention are described below. The processes may be carried out to give a compound of the invention in the form of a free base or as an acid addition salt. A pharmaceutically acceptable acid addition salt may be obtained by dissolving the free base in a suitable organic solvent and treating the solution with an acid, in accordance with conventional procedures for preparing acid addition salts from base compounds. Examples of addition salt forming acids are mentioned above.

The chemicals used in the synthetic routes delineated herein may include, for example, solvents, reagents, catalysts, and protecting group and deprotecting group reagents. Examples of protecting groups are t-butoxycarbonyl (Boc), benzyl and trityl(triphenylmethyl). The methods described below may also additionally include steps, either before or after the steps described specifically herein, to add or remove suitable protecting groups in order to ultimately allow synthesis of the compounds. In addition, various synthetic steps may be performed in an alternate sequence or order to give the desired compounds. Synthetic chemistry transformations and protecting group methodologies (protection and deprotection) useful in synthesizing applicable compounds are known in the art and include, for example, those described in R. Larock, Comprehensive Organic Transformations, VCH Publishers (1989); T.W. Greene and P.G.M. Wuts, Protective Groups in Organic Synthesis, 3rd Ed., John Wiley and Sons (1999); L. Fieser and M. Fieser, Fieser and Fieser's Reagents for Organic Synthesis, John Wiley and Sons (1994); and L. Paquette, ed., Encyclopedia of Reagents for Organic Synthesis, John Wiley and Sons (1995) and subsequent editions thereof. The invention will now be further illustrated by the following non-limiting examples. The specific examples below are to be construed as merely illustrative, and not limitative of the remainder of the disclosure in anyway whatsoever. Without further elaboration, it is believed that one skilled in the art can, based on the description herein, utilize the present invention to its fullest extent. All references and publications cited herein are hereby incorporated by reference in their entirety.

EXAMPLES AND INTERMEDIATE COMPOUNDS

Experimental methods

All reagents were commercial grade and were used as received without further purification, unless otherwise specified. Reagent grade solvents were used in all cases.

LC-MS and UPLC data was recorded under the following conditions:

Method A

Waters Aquity system BEH-C18, 1.7 pm, 2.1 ' 50 mm, 40 °C, 0.5 pL injection, 0.4 mL/min. 0 % MeCN (+0.1 % aq. NH ₃ + 5 % H ₂ O) in H ₂ O (+0.1 % NH ₃ + 5 % MeCN) for 0.2 min, 0-100 % over 3.3 min, hold for 1 min, re-equilibrate 1.0 min, 200-400 nm.

Method B

Agilent 1100 (quaternary pump) XBridge-C18, 5 pm, 4.6 x 50 mm, 25 °C, 2 mL/min, 5 pL injection, 5 % MeCN in H ₂ O (+10 mM ammonium formate), gradient 5-95 % over 3.5 min, hold for 1 min, 200-400 nm.

Method C

Waters Aquity system CSH-C18, 1.7 pm, 2.1 x 50 mm, 40 °C, 0.5 pL injection, 0.4 mL/min. 0% MeCN (+0.1 % formic acid + 5 % H ₂ O) in H ₂ O (+0.1 % formic acid + 5 % MeCN) for 0.2 min, 0-100 % over 3.3 min, hold for 1 min, 200-400 nm. Method D

LC-MS Phenomenex Kinetex XB-C18, 1.7 pm, 2.1 x 50 mm, 40 °C, 0.8 mL/min, 5-100 % MeCN (+0.085 % TFA) in H ₂ O (+0.1 % TFA) over 1.2 min, hold for 0.2 min, re-equilibrate 0.6 min, 200-300 nm.

Method E

Waters Aquity system BEH-C18, 1.7pm, 2.1 ' 50mm, 40°C, 0.5pL injection, 0.4 mL/min. 50 % MeCN (+0.1 % aq. NH ₃ + 5 % H ₂ O) in H ₂ O (+0.1 % NH ₃ + 5 % MeCN) for 0.2 min, 50-100 % over 1 .8 min, hold for 2.5 min, 200-400nm.

Method F

Phenomenex Kinetex XB-C18, 1.7pm, 2.1 x 50mm, 40°C, 0.8mL/min, 5% MeCN (+0.085% TFA) in H ₂ O (+0.1 % TFA) for 0.7min, 5-100% over 3.0min, hold for 0.3min, reequilibrate 1.0min. 200-300nm.

Method G

Phenomenex Kinetex XB-C18, 1.7pm, 2.1 x 50mm, 40°C, 0.8mL/min, 5% MeCN (+0.085%TFA) in H ₂ O (+0.1 %TFA) for 1.0min, 5-100% over 3.0min, hold for 0.2min, reequilibrate 0.8min. 200-300nm

INTERMEDIATE 1

Diethyl 1 -(4-ethoxy-4-oxo-butyl)pyrazole-3,5-dicarboxylate

According to a literature procedure (Pfizer EP1241170A2 (2002), the contents of which are incorporated herein), to a solution of diethyl-3, 5-pyrazoledicarboxylate (10.00g, 47.1 mmol) in MeCN (100mL) was added K ₂ CO ₃ (6.51g, 47.1 mmol) followed by ethyl 4-bromobutyrate (9.19g, 47.1 mmol) and the mixture heated at 80°C for 3.5h. The resulting white suspension was cooled to rt and allowed to stand overnight. The solvent was removed in vacuo and the residue combined with aq. NH4CI (100mL) and EtOAc (100mL) and the phases separated. The aqueous layer was extracted with EtOAc (1x50mL) and combined organics were washed with aq. NaHCOs (100mL), aq. NH4CI (100mL), dried (Na2SO4), filtered and the solvent removed in vacuo to yield the title compound (15.77g, quant.) as a pale yellow oil. LCMS (Method B) 2.89 min, 98 %, [M+H] ⁺ = 327.2.

INTERMEDIATE 2

Diethyl 4-oxo-6,7-dihydro-5H-pyrazolo[1,5-a]pyridine-2,5-dicarboxyla te

To a solution of Intermediate 1 (10.0g, 30.6mmol) in toluene (100mL) was added dropwise a solution of f-BuOK in THF (1.6M in THF, 21.1 mL, 33.7mmol) over 5 min, during which time the temperature rose steadily to 30°C to generate a precipitate in a pale orange solution. The mixture was stirred at rt for 25 min and then at 90°C for 3h to generate a thick slurry. The mixture was then allowed to cool to rt and stirred overnight. The slurry was diluted with EtOAc (150mL), poured into aq. NH4CI (200mL) and 2M HCI (50mL) was added to acidify the aqueous layer. The layers were separated and the aqueous extracted with EtOAc (2x80mL). Combined organics were washed with aqueous NH4CI (2x200 mL), dried (Na2SO4) and filtered. The solvent was removed in vacuo to afford the title compound (7.72g, 90%) as a pale yellow solid. UPLC (Method A) 1.87 min, 99 %, [M+H] ⁺ = 281.2. INTERMEDIATE 3

4-Oxo-6,7-dihydro-5H-pyrazolo[1,5-a]pyridine-2-carboxylic acid

A suspension of Intermediate 2 (5.38g, 19.20mmol) and cone. HCI/H2O (2:1 , 90mL) was heated at 100°C for 6h, cooled to rt and the solvent removed in vacuo. The yellow residue was dissolved in MeCN:THF (1 :4) and the solvent removed in vacuo and this process repeated (x1 ), and then subsequently repeated with MeCN to afford the title compound (3.44g, 99%) as a pale yellow solid. UPLC (Method C) 1.55 min, 97 %, no ionisation observed.

INTERMEDIATE 4

Methyl 4-oxo-6,7-dihydro-5H-pyrazolo[1,5-a]pyridine-2-carboxylate

To a solution of 4-oxo-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridine-2-carboxylic acid (1.83g, 10.1 mmol) in DMF (25mL) was added K2CO3 (2.81g, 20.3mmol) to form a suspension. To this suspension was added iodomethane (0.76mL, 12.2mmol) and stirring continued at rt overnight. To the resulting black mixture was added aq. NH4CI (30mL) and the mixture extracted with EtOAc (3x30mL). Combined organics were washed with aq. sodium thiosulfate (30mL), aq. NaHCOs (30mL), aq. NH4CI (2x30 mL), dried (Na2SO4), filtered and the solvent removed in vacuo to yield the title compound (1.36g, 69%) as an off-white solid. INTERMEDIATE 5

Methyl 4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridine-2-carbox ylate

Two identical reactions were set up in 10 mL microwave vials: To a solution of Intermediate 4 (0.67g, 3.4mmol) in DCE (3.5mL) was added DAST (4.5mL, 34.3mmol) dropwise and the mixture stirred at rt for 2-3 min, sealed and then stirred at rt for 5 days. The two microwave vials were uncapped and the contents of each vial diluted with DCM (10 mL). The reaction mixtures were each pipetted into stirred aq. NaHCOs (100mL) over 10min. Additional DCM (20mL) was added and the mixture stirred for 1-2h. The phases were separated and combined organics were washed with aq. NaHCOs (2x100mL), dried (MgSO4), filtered and the solvent removed in vacuo. The residue was purified by column chromatography on silica (100% DCM to EtOAc/DCM, 1 :99) to afford the title compound (650mg, 44%) as a yellow oil. UPLC (Method A) 2.58 min, 84 %, [M+H] ⁺ = 217.1.

INTERMEDIATE 6

4, 4-Difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridine-2 -carboxylic acid

To a solution of Intermediate 5 (735mg, 3.40mmol) in THF (10mL) was added LiOH (163mg, 6.80mmol) and H2O (0.5mL) and the solution stirred at rt overnight. The resulting yellow solution was acidified to pH 5 using 2M HCI and the solvent partially removed under reduced pressure. The oily residue was diluted with H2O (6mL) and 2M HCI (1 mL) and the resulting thick white precipitate sonicated, filtered, washed on the filter paper with H2O (2x1 OmL) and dried in vacuo to furnish the title compound (551 mg, 80%) as a white powder. UPLC (Method C) 2.37 min, 92 %, [M+H] ⁺ = 203.1.

INTERMEDIATE 7

Benzyl N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-yl)c arbamate

To a suspension of Intermediate 6 (169mg, 0.84mmol) in toluene (10mL) and EtsN (233pL, 1.67mmol) was added benzyl alcohol (434pL, 4.18 mmol) and DPPA (359pL, 1.67mmol) and the reaction heated to 90°C overnight. The resulting orange reaction mixture was diluted with EtOAc (40mL), washed with H2O (10mL), sat. aq. NaHCOs (10mL) and brine (10mL), dried (Na2SO4), filtered and concentrated to an orange oil. The crude oil was purified by column chromatography (toluene/EtOAc, 9:1 to 4:1 to 1 :1) to yield the desired product (145mg, 56%) as an off-white solid. UPLC (Method A) 3.20 min, 80 %, [M+H] ⁺ = 308.

INTERMEDIATE 8

4,4-Difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-amin e

To a suspension of Intermediate 7 (145mg, 0.47mmol) in MeOH (10mL) was added 10% Pd/C (50mg) and the reaction stirred under 1 atm H2 at rt for 16h. The mixture was then filtered through dicalcite and the filtrate concentrated under reduced pressure to yield the title compound (78mg, 95%) as a brown oil, which was used in the next step without further purification. UPLC (Method A) 2.10 min, 72 %, [M+H] ⁺ = 174. INTERMEDIATE 9

Methyl 3-[2-(6-aminopyridin-3-yl)ethynyl]-4-methylbenzoate

To a degassed solution of methyl 3-ethynyl-4-methyl-benzoate (375mg, 2.15mmol), 5-iodopyridin-2-amine (497mg, 2.26mmol) and DIPEA (1.12mL, 6.46mmol) in MeCN (10mL) was added Pd2(PPhs)2Cl2 (75.8mg, O.H mmol) and Cui (20.5mg, 0.11 mmol) and the reaction stirred at rt for 2h. The product was isolated by filtration and purified by SPE using a strong cation exchange resin. Trituration from TBME:heptane afforded the title compound (295mg, 51 %) as a beige solid. UPLC (Method C): 2.30 min, 99.7%, [M+H] ⁺ = 267.0.

INTERMEDIATE 10

Methyl 4-methyl-3-(2-trimethylsilylethynyl)benzoate

Pd(PPh ₃ ) ₂ CI ₂ , Cui,

Et ₃ N, Ethynyltrimethylsilane

A solution of methyl 3-iodo-4-methylbenzoate (50.0g, 0.18mol), EtsN (55.0g, 0.54mol, 75.7mL) and ethynyltrimethylsilane (23.1g, 0.24mol) in EtOAc (700mL) was degassed using 3x vacuum/nitrogen cycles. Pd(PPhs)2Cl2 (1 ,27g, 1 .81 mmol) and Cui (0.35g, 1 .81 mmol) were added and the reaction stirred at rt under nitrogen for 2h. The reaction was concentrated in vacuo to give a dark brown solid. The residue was purified on silica (100% heptane to heptane: EtOAc, 1 :9). Collected fractions were concentrated in vacuo to give the title compound (44.6g, 95%) as a pale yellow solid. UPLC (Method A) 4.26 min, 95.2 %, mass ion not detected. INTERMEDIATE 11

Methyl 3-[2-(2-aminopyrimidin-5-yl)ethynyl]-4-methyl-benzoate

To a degassed solution of methyl 4-methyl-3-(2-triisopropylsilylethynyl)benzoate (331 mg, I .OOmmol) and 5-bromopyrimidin-2-amine (353mg, 2.03mmol) in NMP (4.0mL) with DIPEA (1.06mL, 6.10mmol) was added CsF (462mg, 3.04mmol), Cui (19.3mg, O.IOmmol), and Pd(PPhs)2Cl2 (71.2mg, O.IOmmol). The reaction was heated in the microwave at 150°C for 120 min. 11 such crude reactions were then combined before purification (to give a theoretical yield of 3.27g, 11.0 mmol). The combined reactions were partitioned between tBME (220mL) and brine (half saturated, 220mL) and the biphasic mixture filtered. The layers were separated, and the aqueous phase further extracted with tBME (2x220mL). The combined organics were dried over MgSO4 and concentrated to give the crude product as a brown residue. The residue was triturated with tBME (55mL) and left to stand for 16h. The resulting solid was collected by filtration and washed with tBME (2 x 10mL) and dried in a vacuum oven for 2h to afford the title compound (900mg, 28%) as a tan solid. UPLC (Method A) 3.01 min, 97.3 %, [M+H] ⁺ = 268.1

INTERMEDIATE 12

Methyl 4-methyl-3-[2-(5-methyl-3-pyridyl)ethynyl]benzoate

A solution of methyl 3-ethynyl-4-methyl-benzoate (170mg, 0.98mmol), 3-bromo- 5-methyl-pyridine (0.11 mL, 0.98mmol), DIPEA (0.51 mL, 2.93mmol) in degassed MeCN (4.0mL) was prepared in a microwave vial. Then Pd(PPhs)2Cl2 (34.4mg, 0.05mmol) and Cui (9.3mg, 0.05mmol) were added to the solution and the reaction mixture was sealed in the vial and heated to 100°C for 1 h under microwave irradiation. The reaction mixture was filtered through celite and then concentrated in vacuo. The residue was purified on silica (Biotage Isolera, normal phase, 100% heptane to EtOAc: Heptane, 1 :1) to give the title compound (572mg, 73%) as a yellow solid. UPLC (Method A) 3.64 min, 99.5 %, [M+H] ⁺ = 266.1 .

INTERMEDIATE 13

Methyl 4-methyl-3-[2-[2-(methylamino)pyrimidin-5-yl]ethynyl]benzoat e

To a MW vial was added methyl 3-ethynyl-4-methyl-benzoate (300mg, 1.72mmol), 5-bromo-N-methylpyrimidin-2-amine (389mg, 2.07mmol), MeCN (5.0mL) and DIPEA (0.90mL, 5.17mmol). The reaction mixture was degassed using nitrogen, Cui (16.4mg, 0.09mmol) and PdCl2(PPhs)2 (60.6mg, 0.09mmol) were added and the reaction was heated under MW irradiation for 60min at 100°C. The reaction was concentrated in vacuo. The residue was purified on silica (EtOAc:heptane, 1 :9 to 1 :1) to provide the title compound (302mg, 62%) as a beige solid. UPLC (Method A) 3.33 min, 100 %, [M+H] ⁺ = 282.2.

INTERMEDIATE 14

3-Ethynyl-4-methyl-benzoic acid

To a solution of methyl 4-methyl-3-(2-trimethylsilylethynyl)benzoate (23.5g, 95mmol) in THF (300mL) was added a solution of UOH.H2O (8.0g, 190mmol) in H2O (60mL) and the reaction stirred at rt for 2h. An additional equivalent of LiOH. W (3.4g, 81 mmol) in H2O (30mL) was added and the reaction stirred at rt overnight. I OH.H2O (0.68g, 16.2mmol) in H2O (10mL) was added and the reaction stirred at rt for another 2h. The THF was removed under reduced pressure and the resulting aqueous solution was cooled in an ice/F^O bath and acidified to pH2 by addition of HCI 4.0M (80mL). Addition of HCI gave a light brown solid which was filtered and dried to give the title compound (14.8g, 95.7%) as a pale brown solid. LCMS (Method B) 1.81 min, 98.6%, mass ion not detected.

INTERMEDIATE 15

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-ethynyl-4- methyl-benzamide

To a solution of 3-ethynyl-4-methyl-benzoic acid (0.49g, 3.05mmol), 4,4-difluoro- 6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-amine (440mg, 2.54mmol) in DCM (9.0mL) and DMF (1.0mL) was added Et ₃ N (1.1 OmL, 7.89mmol) and HATU (1.25g, 3.29mmol) under a N2 atmosphere and the reaction was stirred at rt overnight. The reaction was quenched with sat aq NaHCO ₃ (10mL) and diluted with DCM (50mL) the phases were separated and the aqueous extracted with DCM (3x50mL), the combined organics were dried over Na2SO4, filtered and concentrated. The residue was purified on silica (EtOA:heptane, 9:1 to 1 :1) to give the title compound (755mg, 89%) as an off-white solid. UPLC (Method C) 3.20 min, 94.5 %, [M+H] ⁺ = 316.1. INTERMEDIATE 16

5-Bromo-N,1-dimethyl-imidazole-2-carboxamide

Methylamine hydrochloride, Et ₃ N, HATU, DMF

To a cooled mixture of (5-bromo-1-methyl-imidazole-2-carbonyl)oxylithium (300mg, 1.42mmol), EtsN (1.00mL, 7.17mmol), methylamine hydrochloride (290mg, 4.30mmol) in DMF (5.0mL) was added HATU (0.81g, 2.14mmol) portionwise. The mixture was stirred at 0°C for 1 h, allowed to warm to rt and stirred overnight. The reaction was quenched with sat. NaHCOs(IOmL), extracted with EtOAc (3x30mL), dried over Na2SO4 and concentrated to give pale brown oil. The crude oil was purified on silica (EtOAc:heptane, 1 :9 to 2:3), re-dissolved in EtOAc (50mL) and washed with H2O (3x30mL) and brine (30mL) to give the title compound (68.0mg, 21 %) as a white powder. UPLC (Method C) 2.11 min, 97.8 %, [M+H] ⁺ Br 79/81 = 218.0 / 219.9.

INTERMEDIATE 17

Methyl 4-methyl-3-[2-[3-methyl-2-(methylcarbamoyl)imidazol-4- yl]ethynyl]benzoate

To a MW vial was added methyl 3-ethynyl-4-methyl-benzoate (90mg, 0.52mmol), 5-bromo-N,1-dimethyl-imidazole-2-carboxamide (118mg, 0.54mmol), MeCN (3.0mL) and DIPEA (0.27mL, 1 .55mmol). The reaction mixture was degassed using nitrogen, Cui (4.9mg, 0.03mmol) and PdCl2(PPhs)2 (18.2mg, 0.03mmol) were added and reaction was heated under MW irradiation for 60min at 100°C. The reaction was concentrated in vacuo. The residue was purified on silica (acetone :DCM, 1 :19 to 1 :9) to provide the title compound (78.0mg, 49%) as beige solid. UPLC (Method A) 3.22 min, 100.0 %, [M+H] ⁺ = 312.2.

INTERMEDIATE 18

Methyl 4-methyl-3-(2-pyrimidin-5-ylethynyl)benzoate

To a degassed solution of methyl 4-methyl-3-(2-trimethylsilylethynyl)benzoate (500mg, 2.03mmol), 5-bromopyrimidine (387mg, 2.44mmol) and DIPEA (1.06mL, 6.10mmol) in MeCN (10mL) was added Pd(PPhs)2Cl2 (71.2mg, O.IOmmol), Cui (19.3mg, O.IOmmol) and CsF (462mg, 3.04mmol) and the reaction mixture was heated using a microwave reactor (100°C, absorption normal, pre-stirring 10sec) for 2h. A further aliquot of 5-bromopyrimidine (161 mg, 1.01 mmol), Cui (19.3mg, O.IOmmol) and Pd(PPhs)2Cl2 (71.2mg, O.IOmmol) was added and the reaction mixture heated using a microwave reactor (110°C, absorption normal, pre-stirring 10sec) for 1.5h. The mixture was purified on silica (EtOAc:heptane, 3:7 to 100% EtOAc) to give the title compound (234mg, 45%) as a pale yellow fluffy solid. UPLC (Method A) 3.23 min, 98.3 %, no mass ion detected.

INTERMEDIATE 19

3-Bromo-5-(triazol-2-yl)pyridine

A mixture of 1 ,2,3-1 H-triazole (69mg, I .OOmmol), 3,5-dibromopyridine (236mg, 1 .OOmmol) and cesium carbonate (649mg, 1 ,99mmol) in DMF (8.0mL) was heated at 110 °C for 2 days. The reaction mixture was cooled to rt and combined with two additional identical crude reactions. EtOAc (80mL) was added to the combined reaction mixture followed by H2O (150mL). The layers were separated, the aqueous phase extracted with EtOAc (80mL) and combined organics concentrated to yield a crude yellow oil. The crude oil was purified on silica (EtOAc:heptane, 1 :19 to 2:3) to give the title compound (97.0mg, 14%) as a white solid. UPLC (Method A) 2.73 min, 100 %, [M+H] ⁺ = 225.0 / 227.0 (Br 79/81).

INTERMEDIATE 20

4,4-difluoro-3-iodo-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin -2-amine

To a solution of 4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-amine (258mg, 1.49mmol) in DCM (15mL) was added NIS (369mg, 1.64mmol) and the reaction was stirred at rt overnight under nitrogen. Another portion of NIS (134mg, 0.60mmol) was added and the reaction mixture was stirred for 4h. The volatiles were evaporated in vacuo and the residue was purified on silica (acetone: DCM (1 % EtsN), 1 :49) to provide the title compound (173mg, 29%) as a yellow solid. UPLC (Method A) 2.54 min, 74.5 %, [M+H] ⁺ = 300.0.

INTERMEDIATE 21

3-Cyclopropyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a] pyridin-2 -amine

Pd(PPh _g ) ₄ ,

Two reactions were run in parallel. A suspension of 4,4-difluoro-3-iodo-6,7- dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-amine (250mg, 0.84mmol), cyclopropylboronic acid pinacol ester (281 mg, 1.67mmol), Pd(PPhs)4 (97mg, 0.08mmol), K2CO3 (347mg, 2.51 mmol) in a degassed mixture of 1 ,4-dioxane (5.0mL) and H2O (1 .OmL), was heated to 120°C for 3h in a sealed vial under MW irradiation. The reaction mixture was filtered through a syringe filter. Another portion of cyclopropylboronic acid pinacol ester (281 mg, 1.67mmol) and Pd(PPhs)4 (97mg, 0.08mmol) was added and the mixture was heated to 120°C for 3h in sealed vial under MW irradiation. The reaction mixture was filtered through a syringe filter. Another portion of cyclopropylboronic acid pinacol ester (281 mg, 1.67mmol) and Pd(PPhs)4 (97mg, 0.08mmol) was added and the mixture was heated to 120°C for 3h in sealed vial under MW irradiation. The two reaction mixtures were combined before work-up and purification. The mixture was quenched with H2O (15mL) and extracted with EtOAc (3x15mL). The combined organics were washed with brine (15mL), dried over Na2SO4 and concentrated in vacuo to provide the crude product. The crude was further purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :4 to 4:1 , both eluents containing 0.1 Vol% NH3) to give the title compound (29mg, 12%) as a colourless solid. UPLC (Method A) 2.58 min, 74.6 %, [M+H] ⁺ = 214.1.

INTERMEDIATE 22

4,4-Difluoro-3-vinyl-6,7-dihydro-5H-pyrazolo[1,5-a]pyridi n-2-amine

Pd(PPh ₃ ) ₄ , K ₂ C° ₃ ,

A suspension of 4,4-difluoro-3-iodo-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2- amine (160mg, 0.54mmol), 2-vinylboronic acid pinacolester (0.18mL, 1.07mmol), Pd(PPhs)4 (62mg, 0.05mmol), K2CO3 (222mg, 1.61 mmol) in a degassed mixture of 1 ,4-dioxane (4. OmL) and H2O (1.0mL), was heated to 100°C for 1 h in sealed vial under MV irradiation. The reaction mixture was quenched with H2O (15mL) and extracted with EtOAc (3x15mL). The combined organics were washed with brine (15mL), dried over Na2SO4 and concentrated in vacuo to provide the crude product. This was further purified on silica (EtOAc:heptane, 1 :9 to 1 :1) to provide the title compound (76.0 mg, 57%) as a pale yellow solid. UPLC (Method A) 2.52 min, 79.6 %, [M+H] ⁺ = 200.1. INTERMEDIATE 23

3-Ethyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridi n-2-amine

In a stainless steel vessel, to a solution of 4,4-difluoro-3-vinyl-6,7-dihydro-5H- pyrazolo[1 ,5-a]pyridin-2-amine (91.0mg, 0.41 mmol) in MeOH (5.0mL) was added Pd/C (10%, 43.8mg, 0.04mmol). The vessel was sealed and stirred under an atmosphere of hydrogen (at 4 bar) at rt overnight. The mixture was filtered through a pad of Dicalite, eluting with MeOH. Combined organics were concentrated in vacuo. The remaining residue was further purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :4 to 4:1 , both eluents containing 0.1 Vol% NH3) to provide the title compound (58.0mg, 65%) as a colourless oil. UPLC (Method A) 2.51 min, 92.0 %, [M+H] ⁺ = 202.1.

INTERMEDIATE 24

1-(5-Bromo-3-pyridyl)-N,N-dimethyl-pyrrolidin-3-amine

A mixture of 3-(dimethylamino)pyrrolidine (361 mg, 3.17mmol) and 3,5- dibromopyridine (250mg, 1.06mmol) in NMP (2.5mL) was heated in the microwave for 1 h at 100°C. The temperature was then increased to 150 °C and the mixture stirred for 9h. The mixture was then diluted with EtOAc (20mL) and washed with NH4CI solution (saturated, 20mL). The layers were separated and the aqueous phase extracted with further EtOAc (3 x 20mL). The combined organics were washed with H2O (20mL), dried over MgSO4 and the solvent removed under reduced pressure. The residue was purified on silica (Biotage Isolera, normal phase, MeOH:DCM, 1 :99 to 1 :9) to afford the title compound (209mg, 72%) as a beige solid. UPLC (Method A) 2.83 min, 98.0 %, [M+H] ⁺ = 270.1 / 272.1 (Br 79/81). INTERMEDIATE 25

Methyl 3-[2-[5-[3-(dimethylamino)pyrrolidin-1-yl]-3-pyridyl]ethynyl ]-4- methyl-benzoate

To methyl 3-ethynyl-4-methyl-benzoate (110mg, 0.63mmol) and 1-(5-bromo-3- pyridyl)-N,N-dimethyl-pyrrolidin-3-amine (209mg, 0.76mmol) in MeCN (5.0mL) was added DIPEA (0.33mL, 1.89mmol) and the reaction mixture degassed. Pd(PPhs)2Cl2 (22.2mg, 0.03mmol) and Cui (6.0mg, 0.03mmol) were added and the reaction heated to 100°C in the MW for 2h. The solvent was removed under reduced pressure and the residue dissolved in DCM (5.0mL) and filtered. The solvent was removed under reduced pressure and the residue was purified on silica (MeOH:DCM, 1 :99 to 1 :9). The material was then further purified by cationic exchange resin SCX-2 to afford the desired product (159mg, 54%) as a brown film. UPLC (Method A) 3.55 min, 78.3 %, [M+H] ⁺ = 364.3.

INTERMEDIATE 26

3-Bromo-5-(2-methylazetidin-1-yl)pyridine

Pd ₂ (dba) ₃ , XantPhos,

H' To a degassed solution of 3,5-dibromopyridine (165mg, 0.70mmol), Pd2(dba)s (21.3mg, 0.02mmol), XantPhos (26.9mg, 0.05mmol), NaO‘Bu (134mg, 1.39mmol) in dioxane (5.0mL) was added 2-methylazetidine hydrochloride (50.0mg, 0.46mmol). The reaction mixture was then heated to 100°C for 3h. The reaction was quenched by addition of H2O (5mL). The aqueous layer was extracted with EtOAc (3x15mL). The combined organic layers were then washed with brine, dried over MgSO4, filtered and concentrated in vacuo to obtain the crude as a brown oily residue. The residue was purified on silica (EtOAc:Heptane, 1 :19 to 2:3) to afford the title compound (48mg, 42%) as a green oil. UPLC (Method C) 2.99 min, 92.5 %, [M+H] ⁺ = 227.0 I 229.0 (Br 79/81).

INTERMEDIATE 27

Tert-butyl 3-(trifluoromethylsulfonyloxy)-2,5-dihydropyrrole-1 -carboxylate

To a solution of 1-N-Boc-3-pyrrolidinone (0.90g, 4.86mmol) in THF (8.0mL) at - 78°C was added dropwise LiHMDS (1.5M in THF, 3.89mL, 5.83mmol). After stirring for 30min at -78°C, N-phenyl-bis(trifluoromethanesulfonimide) (1.82g, 5.10mmol) in THF (8.0mL) was added dropwise. The mixture was stirred at -78°C for 1 h and warmed to rt for 1 h. The mixture was quenched by addition of NaHCOs (sat. aq., 10mL) and extracted with EtOAc (3x20mL). Organic fractions were combined, dried (Na2SO4), filtered and concentrated to a brown oil. The residue was purified on silica (EtOAc: heptane, 1 :4) to yield semi-pure title compound (776mg, 25%) as a brown oil in 50% purity which was reacted on without any further purification. INTERMEDIATE 28

Tert-butyl 3-(5-amino-3-pyridyl)-2,5-dihydropyrrole-1 -carboxylate

A mixture of tert-butyl 3-(trifluoromethylsulfonyloxy)-2,5-dihydropyrrole-1- carboxylate (576mg, 0.91 mmol), 5-(4,4,5,5-tetramethyl-1 ,3,2-dioxaborolan-2- yl)pyridin-3-amine (400mg, 1.82mmol) and CS2CO3 (1.48g, 4.54mmol) in 1 ,4- dioxane (6.0mL) and H2O (0.6mL) was sparged with N2 for 10min and Pd(PPh3)4 (105mg, 0.09mmol) added. The reaction mixture was then heated to 100°C overnight. The reaction mixture was filtered over celite and the pad washed with EtOAc (20mL). The residue was purified on silica (100% EtOAc to MeOH:EtOAc, 1 :9) and re-purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 2:3 to 4:1 , both eluents containing 0.1 Vol% NH3) to yield the title product (85.0mg, 27%) as an off-white solid. UPLC (Method A) 2.71 min, 99.7 %, [M+H] ⁺ = 262.2.

INTERMEDIATE 29

Tert-butyl 3-(5-amino-3-pyridyl)pyrrolidine-1 -carboxylate

To tert-butyl 3-(5-amino-3-pyridyl)-2,5-dihydropyrrole-1 -carboxylate (80mg, 0.31 mmol) in MeOH (5.0mL) was added Pd/C (10% wt, 50mg). The reaction mixture was stirred under H2 (balloon) overnight. The reaction mixture was filtered over dicalite and the pad washed with MeOH (20mL). The solution was concentrated to give semi-pure title compound (82.0mg, 76%) as a brown residue, which was taken on directly to the next step. INTERMEDIATE 30

Tert-butyl 3-(5-bromo-3-pyridyl)pyrrolidine-1 -carboxylate

To an ice cold solution of tert-butyl 3-(5-amino-3-pyridyl)pyrrolidine-1 -carboxylate (82.0mg, 0.31 mmol) in MeCN (5.0mL) was added tert-butyl nitrite (51.9pL, 0.44mmol). The mixture was stirred at 0°C for 1 h before CuBr2 (73.0mg, 0.33mmol) was added. The mixture was allowed to warm to rt overnight. The reaction mixture was diluted with DCM (20mL). The solution was washed with H2O (10mL), brine (10mL), dried over Na2SO4 and concentrated to a crude brown residue. The residue was purified on silica (EtOAc:heptane, 3:7 to 1 :1) to give the title compound (58.0mg, 51 %) as an off-white solid. UPLC (Method A) 3.35 min, 89.9 %, [M+H] ⁺ = 327.1 / 329.1 (Br 79/81).

INTERMEDIATE 31

Tert-butyl 3-[5-[2-[5-[(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyri din-2- yl)carbamoyl]-2-methyl-phenyl]ethynyl]-3-pyridyl]pyrrolidine -1 -carboxylate

To a degassed solution of N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin- 2-yl)-3-ethynyl-4-methyl-benzamide (55.9mg, 0.18mmol), tert-butyl 3-(5-bromo-3- pyridyl)pyrrolidine-1-carboxylate (58.0mg, 0.18mmol) and DIPEA (0.09mL, 0.53mmol) in MeCN (2.0mL) was added Pd(PPhs)2Cl2 (6.2mg, 0.01 mmol) and Cui (1.7mg, 0.01 mmol). The reaction mixture was heated at 100°C for 1 h in the microwave. The reaction mixture filtered over dicalite and concentrated in vacuo. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :1 to 4:1 , both eluents containing 0.1 Vol% NH3). The relevant fractions were combined, concentrated, azeotroped with toluene (2x1 OmL) and freeze-dried to give the title compound (44.0mg, 42%) as an off-white solid. LCMS (Method B) 3.52 min, 94.9 %, [M+H] ⁺ = 562.5.

INTERMEDIATE 32

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-(5- pyrrolidin-3-yl-3-pyridyl)ethynyl]benzamide dihydrochloride

To a solution of tert-butyl 3-[5-[2-[5-[(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5- a]pyridin-2-yl)carbamoyl]-2-methyl-phenyl]ethynyl]-3-pyridyl ]pyrrolidine-1- carboxylate (42.0mg, 0.07mmol) in DCM (2. OmL) was added HCI (4.0M in dioxane, 0.19mL, 0.75mmol). The resultant reaction mixture was stirred at rt overnight. The reaction mixture was concentrated and the residue suspended in MTBE (5. OmL). The mixture was filtered and the solid dried to give the title compound (26.0mg, 61 %) as an off-white solid. LCMS (Method B) 2.41 min, 94.4 %, [M+H] ⁺ = 462.4.

INTERMEDIATE 33

3-[2-(5-Bromo-3-pyridyl)ethynyl]-N-(4,4-difluoro-6,7-dihy dro-5H- pyrazolo[1,5-a]pyridin-2-yl)-4-methyl-benzamide

To a MW vial was added N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2- yl)-3-ethynyl-4-methyl-benzamide (60.0mg, 0.19mmol), 3,5-dibromopyridine (67.6mg, 0.29mmol), MeCN (2.0mL) and DIPEA (99.4pL, 0.57mmol). The reaction mixture was degassed using nitrogen, Cui (1.8mg, 0.01 mmol) and PdCl2( hs)2 (6.7mg, 0.01 mmol) were added and reaction was heated under MW irradiation for 60min at 100°C. The reaction was concentrated in vacuo. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :9 to 4:1 , both eluents containing 0.1 Vol% NH3). The fractions containing desired product were concentrated in vacuo to provide the title compound (32.0 mg, 35%) as an off-white solid. UPLC (Method C) 3.59 min, 96.8 %, [M+H] ⁺ = 471.1/473.1 (Br 79/81).

INTERMEDIATE 36

3-Bromo-5-[2-(trifluoromethyl)azetidin-1-yl]pyridine

Pd ₂ (dba) ₃ ,

To a degassed solution of 3,5-dibromopyridine (568mg, 2.40mmol), Pd2(dba)s (73.2mg, 0.08mmol), Xantphos (92.5mg, 0.16mmol), NaO‘Bu (461 mg, 4.80mmol) in dioxane (15.0mL) was added 2-(trifluoromethyl)azetidine (200mg, 1.60mmol). The reaction mixture was then heated to 100°C for 3h. The reaction was then quenched by addition of H2O (30mL). The aqueous mixture was then extracted with EtOAC (3x40mL). The combined organic layers were then washed with brine, dried over MgSO4, and concentrated in vacuo to obtain the crude product as an orange oil. The residue was purified on silica (EtOAc:heptane, 1 :9 to 2:3) and re-purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 2:3 to 100 % MeCN, both eluents containing 0.1 Vol% NH3) to afford the title compound (52.0mg, 11 %) as an off-white solid which contained 8% dibromopyridine starting material, and was taken on directly to the next step without further purification. UPLC (Method A) 3.28 min, 91.8 %, [M+H] ⁺ = 281.0/283.0 (Br 79/81). INTERMEDIATE 37

2-Chloro-N-(2-hydroxy-2-methyl-propyl)acetamide

To 1-amino-2-methyl-propan-2-ol (5.00g, 56.1 mmol) in DCM (80mL) and 2M NaOH (39.3mL, 78.5mmol) at 0°C was added chloroacetyl chloride (5.4mL, 67.3mmol) dropwise. The reaction was stirred for 2h at rt, the layers were separated, the organic layer dried over MgSO4 and the solvent removed in vacuo to give the title compound (5.60g, 60%) as a colourless oil. ¹ H NMR (400MHz, CDCI ₃ ): 6H 7.02 (s, 1 H), 4.13 (m, 3H), 3.35 (d, J = 6.1 Hz, 2H), 1.30-1.25 (m, 6H) ppm.

INTERMEDIATE 38

6,6-Dimethylmorpholin-3-one

To Intermediate 37 (5.60g, 33.8mmol) in IPA (40mL) at 0°C under N2 was added tert-butoxypotassium (7.59g, 67.6mmol) and the reaction mixture warmed to rt over 16h. The reaction was neutralised with HCI solution (2M) to pH 7 and the organic solvent removed under reduced pressure. The resulting aqueous phase was extracted with DCM (3x20mL). The combined organics were dried over MgSO4 and the solvent removed under reduced pressure to give the crude product (1.99g) as a yellow oil. This was purified on silica (100% EtOAc to MeOH:EtOAc, 1 :9) to afford the title compound as a crystalline white solid (832mg, 19.1 %). ¹ H NMR (400MHz, CDCI3): b _H 6.39 (s, 1 H), 4.18 (s, 2H), 3.25 (d, J = 2.4 Hz, 2H), 1.33 (s, 6H) ppm. INTERMEDIATE 39

Methyl 2-(2,2-dimethyl-5-oxo-morpholin-4-yl)acetate

To a stirred solution of Intermediate 38 (832mg, 6.44mmol) in THF (25mL) under N2 at rt was added NaH (60% in mineral oil, 258mg, 6.44mmol) in portions. The reaction was stirred at rt for 40 min followed by addition of methyl 2-bromoacetate (608pL, 6.44mmol) dropwise at rt and the reaction stirred at rt for 16h. The reaction was carefully diluted with H2O (20mL) and the layers separated. The aqueous phase was extracted with EtOAc (3x1 OmL). The combined organics were washed with brine (20mL), dried (MgSO4) and concentrated in vacuo to give crude product (1.20g) as a pink oil. The residue was purified on silica (EtOAc:heptane, 7:3 to 100% EtOAc) to afford the title compound (726mg, 56%) as a colourless oil. ¹ H NMR (400MHz, CDCI3): 6H 4.22 (s, 2H), 4.15 (s, 2H), 3.75 (s, 3H), 3.28 (s, 2H), 1.36 (s, 6H) ppm.

INTERMEDIATE 40

2-(2,2-Dimethyl-5-oxo-morpholin-4-yl)acetic acid

To a stirred solution of Intermediate 39 (726mg, 3.61 mmol) in THF (20mL) was added TMSOK (669mg, 4.69mmol) at rt followed by stirring for 16h. The reaction was diluted with TBME (30mL), filtered under vacuum and the filtrate discarded. The filter cake was dissolved in H2O (10mL), acidified to pH 2 using 2M HCI, saturated by addition of solid NaCI and extracted with EtOAc (8x1 OmL). The combined organics were dried (MgSO4) and concentrated in vacuo to give the title compound (378mg, 56%) as a white solid. ¹ H NMR (400MHz, CDCh): 6H 4.24 (s, 2H), 4.17 (s, 2H), 3.31 (s, 2H), 1.36 (s, 6H) ppm.

INTERMEDIATE 41

2-(2,2-Dimethyl-5-oxo-morpholin-4-yl)acetamide

To a stirred solution of Intermediate 40 (378mg, 2.02mmol) in 1 ,4-dioxane (10mL) at rt was added pyridine (81 pL, 1.01 mmol), ammonium carbonate (194mg, 2.02mmol) and BOC2O (617mg, 2.83mmol) and the reaction stirred for 16h at rt. The reaction was concentrated in vacuo and the residue purified on silica (100% EtOAc to MeOH:EtOAc, 1 :4) to afford the title compound (349mg, 92.8%) as a white solid. ¹ H NMR (400MHz, CDCh): 5H 6.20 (s, 1 H), 5.38 (s, 1 H), 4.22 (s, 2H), 4.02 (s, 2H), 3.35 (s, 2H), 1.34 (s, 6H) ppm.

INTERMEDIATE 42

2-Bromo-6,6-dimethyl-5,8-dihydroimidazo[2,1-c][1,4]oxazin e

To a microwave vial containing Intermediate 41 (160mg, 0.86mmol) in MeCN (4.0mL) was added POBrs (1 .48g, 5.16mmol). The vial was then heated to 120°C in a Biotage initiator for 35min. The reaction was then added dropwise to a stirring solution of H2O (10mL) and DCM (10mL) at 0°C. Solid K2CO3 was then added to basify the aqueous layer to pH 10. The organic layer was separated and the aqueous extracted with 4:1 DCM:IPA (5x10mL). The combined organic layers were dried over MgSO4, filtered and concentrated. The crude residue was purified on silica (100% heptane to EtOAc:heptane, 3:2) to afford the title compound (35.0mg, 17.6%) as a brown oil. This was used in the next step without further purification. UPLC (Method A) 2.44min, 28.3 %, [M+H] ⁺ = 231.0/233.0.

INTERMEDIATE 43

Methyl 4-methyl-3-(2-triisopropylsilylethynyl)benzoate

A solution of methyl 3-iodo-4-methylbenzoate (30.0g, 109mmol), ethynyl(triisopropyl)silane (26.8mL, 120mmol) and DIPEA (56.8mL, 326mmol) in EtOAc (400mL) was degassed for 15min at rt. Then Cui (621 mg, 3.26mmol) and PdCl2(PPhs)2 (2.29g, 3.26mmol) were added. The reaction mixture was then heated to 60°C overnight. The reaction mixture was allowed to cool to rt, filtered and concentrated. The residue was purified on silica (100 % heptane to toluene:heptane, 1 :1) to give the title compound (36.6g, 100%) which was used without further purification. UPLC (Method A) 3.81 min, 98.6%, no ionisation.

INTERMEDIATE 44

4-Methyl-3-(2-triisopropylsilylethynyl)benzoic acid

To a solution of methyl 4-methyl-3-(2-triisopropylsilylethynyl)benzoate (36.6g, 111 mmol) in THF (200mL) and MeOH (150mL) was added a solution of KOH (7.5g, 133mmol) in H2O (200mL). The reaction was stirred at 55°C for 3h. The reaction was concentrated to ~150mL and the aqueous layer was acidified to pH 1 with addition of HCI 2N. The aqueous was then extracted with EtOAc (3x200mL). The combined organics were dried over Na2SO4 and concentrated to give crude. This was triturated with EtOAc to give the title compound (23.4g, 67%) as a white solid. The filtrate was concentrated and the solid was triturated with heptane to give additional title compound (7.58g, 22%). UPLC (Method A) 0.65 min, 100%, [M+H]’ = 315.2.

INTERMEDIATE 45

4-Methyl-3-(2-triisopropylsilylethynyl)benzamide

(NH ₄ ) ₂ CO ₃ , pyridine, di-tert-butyl dicarbonate, 1 ,4-dioxane

To a solution of 4-methyl-3-(2-triisopropylsilylethynyl)benzoic acid (2.00g, 6.32mmol) in 1 ,4-dioxane (25mL) at rt was added pyridine (0.25mL, 3.16mmol) and ammonium carbonate (721 mg, 6.32mmol) followed by di-tert-butyl dicarbonate (1.93g, 8.85mmol). The reaction was stirred at rt for 2d under a N2 atmosphere. The reaction was dry-loaded onto silica and purified on silica (100% heptane to EtOAc: heptane, 2:3) to give the title compound (2.01g, 91 %) as a colourless powder. UPLC (Method A) 2.84min, 100 %, [M+H] ⁺ = 316.3.

INTERMEDIATE 46

N-(5,5-dimethyl-6,8-dihydroimidazo[2,1-c][1,4]oxazin-2-yl )-4-methyl-3-(2- triisopropylsilylethynyl)benzamide

An RBF was charged with 4-methyl-3-(2-triisopropylsilylethynyl)benzamide (1.50g, 4.75mmol), 1 ,4-dioxane (60mL), Cul (905mg, 4.75mmol) and CS2CO3 (3.87g, 11.9mmol). The mixture was degassed for 30min before addition of trans N,N'-dimethylcyclohexane-1 ,2-diamine (0.75mL, 4.75mmol), followed by a degassed solution of 2-bromo-5,5-dimethyl-6,8-dihydroimidazo[2,1- c][1 ,4]oxazine (1.08g, 4.67mmol) in 1 ,4-dioxane (20mL) and the resultant mixture heated to 100°C overnight under N2. The reaction was allowed to cool to rt, filtered through cotton wool and concentrated in vacuo. The green oil was solubilized in DCM (100mL), washed with sat. aq. NH4OH (3x30mL), dried over Na2SO4, filtered and concentrated in vacuo to give the crude material as a black greenish oil. The residue was purified on silica (100% toluene to acetone:toluene, 1 :4) to afford the title compound (689mg, 30%). UPLC (Method A) 3.36min, 93.6 %, [M+H] ⁺ = 466.3.

INTERMEDIATE 47

N-(5,5-dimethyl-6,8-dihydroimidazo[2,1-c][1,4]oxazin-2-yl )-3-ethynyl-4- methyl-benzamide

To a solution of N-(5,5-dimethyl-6,8-dihydroimidazo[2,1-c][1 ,4]oxazin-2-yl)-4- methyl-3-(2-triisopropylsilylethynyl)benzamide (698mg, 1.50mmol) in THF (10mL) was added 1 M TBAF in THF (1.70mL, 1.70mmol), the mixture stirred for 45min at rt under N2 atmosphere and the solution concentrated to give a dark green oil. The residue was re-dissolved in EtOAc (100mL), washed with NH4CI (50mL), extracted with EtOAc (1x50mL), the organics combined, dried over Na2SO4 and concentrated to give a brown oil. This was triturated from TBME:heptane to give the title compound (354mg, 78%) as a pale beige powder. UPLC (Method A) 2.95min, 99.0%, [M+H] ⁺ = 310.2.

INTERMEDIATE 48

3-Ethynylimidazo[1,2-a]pyridine Ethynyltrimethylsilane (1.41 mL, 10.20mmol) and /V-cyclohexylcyclohexanamine (1.21 mL, 6.09mmol) were added to a solution of 3-bromoimidazo[1 ,2-a]pyridine (1.00g, 5.08mmol), Pd(PPhs)2Cl2 (89.1 mg, 127|jmol) and Cui (33.8mg, 178|jmol) in MeCN (10mL), the solution sparged with N2 for 10 min and then heated to 80°C for 5 min to form a very thick slurry. The reaction was cooled to rt, diluted with MeCN (40mL) and re-heated at 80°C for 3h. The reaction mixture was then concentrated in vacuo and the residue partitioned between DCM (100mL) and H2O (100mL). The aqueous layer was extracted with DCM (100mL) and the organic layers combined, dried (MgSO4) and concentrated in vacuo. The residue was dissolved in MeOH (20mL), K2CO3 (701 mg, 5.08mmol) was added and the reaction was stirred for 30 min at rt. The reaction mixture was filtered and concentrated in vacuo. The residue was purified on silica (100% iso-hexanes to 100% EtOAc). The product was dried in a vacuum oven at 50°C for 3h to give the title compound (473mg, 66%) as a brown solid. LC-MS (Method D) 0.50 min, [M+H] ⁺ = 143.0.

INTERMEDIATE 49

N-(5-tert-butylisoxazol-3-yl)-3-iodo-4-methyl-benzamide

DIPEA (1.32mL, 7.63mmol) was added to a solution of 3-iodo-4-methyl-benzoic acid (1.00g, 3.82mmol), 3-amino-5-tert-butylisoxazole (535mg, 3.82mmol) and HATU (1 ,45g, 3.82mmol) in DCM (20mL) and the reaction stirred at reflux for 96h. The mixture was partitioned between DCM (50mL) and H2O (50mL) and the aqueous layer extracted with DCM (50mL). Combined organics were dried (MgSO4) and concentrated in vacuo. The residue was purified on silica (100% isohexanes to 100% EtOAc). The product was dried in a vacuum oven at 60°C for 2h to give the title compound (767mg, 51 %) as a white solid. LC-MS (Method D) 1.47 min, [M+H] ⁺ = 385.2. INTERMEDIATE 50

Methyl 3-ethynyl-4-methyl-benzoate

A solution of methyl 3-iodo-4-methylbenzoate (6.00g, 21.7mmol), ethynyltrimethylsilane (7.52mL, 54.3mmol) and EtsN (9.09mL, 65.2mmol) in MeCN (50mL) was degassed with N2 for 15 min. Cui (207mg, 1.09mmol) and Pd(PPh3) ₂ Cl2 (763mg, 1.09mmol) were added and the mixture was degassed with N2 for 5 min then stirred under N2 for 45 min. The reaction mixture was concentrated in vacuo, the sample was redissolved in MeOH (50 mL), K2CO3 (3.00g, 21.7mmol) was added and the mixture was stirred for 1 h at rt. An additional portion of K2CO3 (3.00g, 21.7mmol) was added after 15min. The reaction mixture was concentrated in vacuo and the sample was redissolved in EtOAc (75mL) and H2O (75mL). The aqueous phase was extracted with EtOAc (2x35mL) and the combined organic phases were washed with brine (50mL) and concentrated in vacuo. The sample was purified on silica (reverse phase, 10% to 100% MeOH in 10% MeOH/H2O) and dried in a vacuum oven at 60°C for 18h to give the title compound (1.40g, 37%) as a dark black solid. UPLC (Method G) 2.76 min, 100 %.

INTERMEDIATE 51

3-Ethynyl-4-methyl-benzoic acid

Intermediate 50 (700mg, 4.0mmol) and LiOH monohydrate (512mg, 11.9mmol) were dissolved in THF:H2O (10mL, 1 :1) and the reaction stirred at rt for 2h. A further portion of LiOH monohydrate (512mg, 11.9mmol) was added and the reaction stirred at rt for 3d. The THF was removed in vacuo and the residue acidified with 1 M HCI. The product was extracted with EtOAc (4x50mL), dried (MgSO4) and concentrated in vacuo to give the title compound (200mg, 29%) as a light brown solid. LC-MS (Method F) 2.27 min, no ionisation observed.

INTERMEDIATE 52

3-Ethynyl-4-methyl-N-[1-(2-morpholinoethyl)pyrazol-3-yl]b enzamide

1-[2-(Morpholin-4-yl)ethyl]-1/7-pyrazol-3-amine (251 mg, 1.28mmol), Intermediate 51 (200mg, 1.16mmol, 93 % pure), DIPEA (202pL, 1.16mmol) and HATU (574mg, 1.51 mmol) were dissolved in DCM (40mL) and the reaction stirred at rt for 18h. The mixture was washed with sat. aq. NaHCOs (30mL), dried (MgSO4) and concentrated in vacuo. The residue was purified on silica (100% /so-hexanes to 100% EtOAc) and re-purified on silica (100% DCM to MeOH:DCM,1 :4) to give the title compound (377mg, 92%) as a light brown solid. LC-MS (Method F) 2.04 min, [M+H] ⁺ = 339.2.

INTERMEDIATE 53

6-Fluoroisoquinolin-3-amine

To MeOH (15mL) was added 2,2-diethoxyacetonitrile (3.00g, 23.2mmol) and a methanolic solution of NaOMe (0.25g, 4.7mmol in 1 mL MeOH) and the reaction stirred at rt for 24h. 4-Fluorobenzylamine (2.39mL, 20.9mmol) was then added and the reaction stirred for a further 24h at rt. The reaction mixture was concentrated in vacuo and the vessel was cooled to 0°C before addition of concentrated sulfuric acid (15.0mL) and further stirring at rt for 24h. The reaction was neutralised to pH 7 using 4M KOH, the product extracted using DCM (3x150mL), dried (MgSO4) and concentrated in vacuo. The residue was purified on silica (100% /so-hexanes to 100% EtOAc) to give the title compound (292mg, 7.8%) as a brown solid. LC-MS (Method F) 1.38 min, [M+H] ⁺ = 163.0.

INTERMEDIATE 54

6-Fluoro-4-iodo-isoquinolin-3-amine

Intermediate 53 (292mg, 1.66mmol, 92% pure) and NIS (347mg, 1.54mmol) were dissolved in MeOH (75mL) and the reaction was stirred at rt for 3h. A further portion of NIS (187mg, 0.83mmol) was then added and the reaction was stirred at rt for a further 18h . The solvents were removed in vacuo and the residue purified on silica (100% /so-hexanes to 100% EtOAc) to give the title compound (296mg, 57%) as a brown solid. LC-MS (Method F) 2.15 min, [M+H] ⁺ = 289.

INTERMEDIATE 55

Methyl 4-methyl-3-(2-trimethylsilylethynyl)benzoate

A solution of methyl 3-iodo-4-methylbenzoate (50.0g, 0.18mol), EtsN (55.0g, 0.54mol) and ethynyltrimethylsilane (23.1g, 0.24mol) in EtOAc (700mL) was degassed using three cycle of vacuum/N2. Pd(PPh3)2Cl2 (1.27g, 1.81 mmol) and Cui (0.35g, 1 .81 mmol) were added and the reaction stirred at rt under N2 for 2h. The reaction was concentrated in vacuo and the dark brown solid purified on silica (100% heptane to heptane:EtOAc, 9:1) to yield the title compound (44.6g, 95.1 %) as a pale yellow solid. UPLC (Method A) 4.26 min, 95 %, mass ion not detected. INTERMEDIATE 56

Methyl 3-(2-imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-benzoate

A mixture of Intermediate 55 (318mg, 1.29mmol), 3-bromoimidazo[1 ,2- b]pyridazine (307mg, 1.55mmol), triethylamine (0.54mL, 3.87mmol), Cui (25mg, 0.13mmol), Pd(PPhs)2Cl2 (91 mg, 0.13mmol) and CsF (392mg, 2.58mmol) in MeCN (4.0mL) in a microwave tube was degassed with N2 for 2 min and heated at 100°C in a microwave for 2h. The reaction mixture was combined with two further batches of the reaction (1.29 and 0.81 mmol) with DCM (50mL) and H2O (50mL) added to the mixture. The layers were separated and the aqueous phase extracted with DCM (2x50mL). Combined organics were concentrated and the crude product purified on silica (DCM:MeOH, 99:1 to 9:1) and recrystallised with MeCN (15mL) to yield the title compound (238mg, 24%) as a yellow solid. UPLC (Method A), 3.21 min, 99 %, [M+H] ⁺ = 292.2.

INTERMEDIATE 57

3-(2-lmidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-benzoi c acid

To a solution of Intermediate 56 (238mg, 0.82mmol) in MeOH (10mL) and THF (10mL) at rt was added UOH.H2O (103mg, 2.45mmol) in H2O (2.0mL) and the resulting mixture stirred at rt overnight. The solvent was then removed in vacuo and H2O (10mL) added to the residue, which was acidified by aq. HCI to pH 1-2. The solvent was removed in vacuo to give the title compound (320mg) as a brown solid, which was used in the next step without further purification. UPLC (Method A), 1.87 min, 99 %, [M+H] ⁺ = 278.2. INTERMEDIATE 58

6'-Nitrospiro[1,3-dithiolane-2,T-indane]

Ethane-1 ,2-dithiol (1.68g, 17.9mmol, 1.10eq), 6-nitroindan-1-one (2.88g, 16.2mmol, 1.00eq), p-toluene sulfonic acid (0.56g, 3.3mmol, 0.20eq) and toluene (15mL) were heated under Dean Stark conditions at 100°C for 24h. The reaction was then allowed to cool to rt and the toluene removed in vacuo. The residue was purified by column chromatography on silica (EtOAc:heptane, 1 :9) to yield the title product (4.05g, 98%) as a yellow oil. UPLC (Method A) 1.71 min, 100 %, no ionisation observed.

INTERMEDIATE 59

2-Bromo-1,1-difluoro-6-nitro-indane

To a solution of 1 ,3-dibromo-5,5-dimethyl-imidazolidine-2, 4-dione (18.1g, 63.2mmol) in anhydrous DCM (90mL) at -70°C was added HF-pyridine (18.8mL, 70%) dropwise and the reaction stirred at -70°C for 30min before addition of a solution of Intermediate 58 (4.00g, 15.8mmol) in DCM (10mL) dropwise and further stirring for 4h. The mixture was then allowed to warm to rt and stirred overnight. To the dark brown mixture was added NaOH (2M, 50mL) and NaHSOs (3M, 5.0mL) and the phases separated. The aqueous phase was extracted with DCM (2x80 mL) and the combined organics were concentrated in vacuo to give the crude product (4.02g) as an orange oil. This was purified on silica (EtOAc:heptane, 1 :9 to 3:7) to give the title compound (3.63g) as a yellow oil, which was used in the next step without further purification. UPLC (Method E), 1.30 min, 80 %, no ionisation.

INTERMEDIATE 60

1,1-Difluoro-6-nitro-indene

DBU (3.3mL, 22.2mmol) was added to a solution of Intermediate 59 (3.63g, 13.1 mmol) in anhydrous DCM (50mL) at rt for 2h. To the mixture was then added aq. HCI (50mL, 2M) and the phases separated. The aqueous phase was washed with DCM (2x50 mL) and combined organics concentrated in vacuo to give the crude product (3.01g) as a purple solid. The crude product was purified on silica (EtOAc: heptane, 1 :9 to 3:7) to yield the title compound (2.62g) as a yellow solid, which was used in the next step without further purification. UPLC (Method E) 0.99 min, 83 %, no ionisation.

INTERMEDIATE 61

1,1-Difluoro-6-nitro-indane

Hydrazine monohydrate (2.58mL, 53.2mmol) was added to a solution of Intermediate 60 (2.62g, 13.3mmol) and 2-nitrobenzenesulfonyl chloride (5.89g, 26.6mmol) in MeCN (60mL) at 0°C dropwise to give a yellow suspension. The reaction mixture was allowed to warm to rt, resulting in the formation of a clear solution, which was stirred at rt for 72h. The MeCN was removed in vacuo at 30°C and H2O (80mL) was added to the reaction mixture to dissolve the precipitate. The crude product was extracted with EtOAc (3x50 mL) and combined organics were concentrated in vacuo. The crude product was purified on silica (EtOAc:heptane, 1 :9 to 3:7) to yield the title compound (2.00g, 76%) as a yellow oil which solidified on standing. UPLC (Method E), 1.12 min, 99.6 %, no ionisation.

INTERMEDIATE 62

3-bromo-1 , 1 -difluoro-6-nitro-indane

Intermediate 61 (500mg, 2.51 mmol), AIBN (41 mg, 0.25mmol) and NBS (536mg, 3.01 mmol) in carbon tetrachloride (30mL) were heated at reflux (90°C) overnight. This reaction was then repeated on an additional batch of material and both reactions combined after cooling to rt. The crude product was purified on silica (EtOAc/heptane, 3:97), to yield the title compound (788mg, 56%) as a yellow oil, which contained 16% starting material by UPLC and was used without further purification. UPLC (Method E) 1.39 min, 83 %, no ionisation.

INTERMEDIATE 63

1 -(3,3-difluoro-5-nitro-indan-1 -yl)-4-methyl-piperazine

1 -Methylpiperazine (568mg, 5.7mmol) was added to Intermediate 62 (788mg, 2.8mmol) and potassium carbonate (783mg, 5.7mmol) in DMF (10mL) at rt and the resulting mixture stirred at rt for 4h. To the reaction was then added H2O (100mL) and EtOAc (3x50 mL) and the solvent removed in vacuo from the combined organics to yield a purple oil. This was purified on silica (MeOH/DCM, 1 :99 to 1 :9) to yield the title product (100mg, 12%) as a dark green solid. UPLC (Method A) 3.07 min, 78 %, [M+H] ⁺ = 298.2. INTERMEDIATE 64

3,3-difluoro-1 -(4-methylpiperazin-1 -yl)indan-5-amine

Pd/C (15.0mg, 10% wt) was added to Intermediate 63 (100mg, 0.34mmol) in IPA (5mL). The resulting reaction mixture was hydrogenated at rt at 1atm for 3h. The reaction mixture was filtered through Celite and washed with IPA (5mL). The solvent was removed in vacuo to give the title compound (103mg) as a grey solid, which was taken on directly to the next step. UPLC (Method A) 2.31 min, 67 %, [M+H] ⁺ = 268.2.

INTERMEDIATE 65

6-Aminopyridine-2 -carbohydrazide

To a solution of methyl 6-aminopyridine-2-carboxylate (152mg, I .OOmmol) in MeOH (2.0mL) was added hydrazine monohydrate (0.15mL, 3.00mmol). The mixture was heated at 78°C under nitrogen for 3h. The mixture was cooled to rt and the solvent removed. The resulting solid was washed with a mixture of EtOAc and TBME (1 :3, 15mL) and then with TBME (10mL). The resulting solid was dried to provide the title compound (117mg, 77%) as an off-white solid, which was used without further purification in the next step. INTERMEDIATE 66

N,6-bis[(E)-dimethylaminomethyleneamino]pyridine-2-carbox amide

A stirred mixture of 6-aminopyridine-2-carbohydrazide (117mg, 0.77mmol) and DMF-DMA (5.0mL, 37.60mmol) was heated at 110°C for 24h. The mixture was cooled to rt and the volatiles were removed in vacuo. The resulting solid was suspended in TBME. The mixture was put in an ultrasound bath for 5 min, the solvent was removed and the solid was dried to provide the title compound (220mg, 102%) which was used crude in the next step without further purification. UPLC (Method A) 1.97 min, 93.2 %, ES ⁺ : 263.1 [M+H] ⁺ .

INTERMEDIATE 67

6-(4-lsopropyl-1,2,4-triazol-3-yl)pyridin-2-amine

To a stirred solution of N,6-bis[(E)-dimethylaminomethyleneamino]pyridine-2- carboxamide (220mg, 0.78mmol) in a mixture of MeCN (1.0mL) and AcOH (0.25mL, 4.44mmol) was added isopropylamine (0.34mL, 3.91 mmol). The mixture was stirred at 100°C under nitrogen for 16h. The reaction mixture was quenched with H2O and the pH adjusted to 8 with 2M NaOH aq. solution. The mixture was extracted with EtOAc (3x15 mL) and combined organics washed with brine (1 OmL), dried over Na2SO4 and concentrated to provide the title compound (50mg, 22%) as a yellow oil, which was taken on directly to the next step. UPLC (Method A) 1.86 min, 68.8 %, ES ⁺ : 204.1 [M+H] ⁺ . INTERMEDIATE 68

[3-[2-(3-Pyridyl)ethynyl]benzoyl]oxypotassium

To a solution of methyl 3-[2-(3-pyridyl)ethynyl]benzoate (237mg, I .OOmmol) in THF (10mL) was added KOTMS (385mg, 3.00mmol). The reaction was stirred at rt overnight under nitrogen. The volatiles were evaporated in vacuo. The resulting solid was suspended in TBME (20 mL) and put in an ultrasound bath for 5 min. The solvent was removed and the solid was dried to provide the title compound (288mg, 110%) as a light yellow solid, which was used in the next step without further purification. UPLC (Method A) 1.79 min, 100 %, ES ⁺ : 224.1 [M-K+2H] ⁺ .

INTERMEDIATE 69

3-[2-(3-Pyridyl)ethynyl]benzoyl chloride

To a suspension of [3-[2-(3-pyridyl)ethynyl]benzoyl]oxypotassium (288mg, 0.99mmol) in DCM (5.0mL) was added oxalyl chloride (0.11 mL, 1.29mmol) and few drops of DMF. The reaction was stirred overnight at rt under nitrogen. Another portion of oxalyl chloride (0.09mL, 0.99mmol) was added to the reaction mixture and the reaction was stirred at rt overnight under nitrogen. Another portion of oxalyl chloride (0.09mL, 0.99mmol) was added to the reaction mixture and the reaction was stirred at rt under nitrogen for 2h. The volatiles were evaporated in vacuo. Toluene (10mL) was added to the reaction mixture and the volatiles were evaporated in vacuo. The residue was dissolved in DCM (10mL) and filtered. The solid was washed with DCM (1 OmL) and the organic phases were combined and concentrated in vacuo to provide a mixture of 3-[2-(3-pyridyl)ethynyl]benzoyl chloride and 3-[2-(3-pyridyl)ethynyl]benzoic acid. To this mixture suspended in DCM (5.0 mL) was added oxalyl chloride (0.11 mL, 1.29mmol). The reaction was stirred for2h at rt under nitrogen. The volatiles were evaporated in vacuo. Toluene (10mL) was added to the mixture and the volatiles were evaporated in vacuo. The residue was dissolved in DCM (10mL) and filtered. The solid was washed with DCM (10mL) and the organic phases were combined and concentrated in vacuo to provide the title compound (230mg, 92%) as an orange oil, which was used crude in the next step. UPLC (Method A) 3.23 min, 95.8 %, ES ⁺ : 238.1 [MH- CI+OMe] ⁺ .

INTERMEDIATE 70

Methyl 4-fluoro-3-[2-(3-pyridyl)ethynyl]benzoate

Methyl 3-bromo-4-fluoro-benzoate (1.00g, 4.30mmol), 3-ethynylpyridine (665mg, 6.45mmol), triethylamine (1 ,82mL, 13.1 mmol) and EtOAc (20mL) were added to a two-neck round bottom flask, degassed with N2 for 15 min, then Cui (26.8mg, 0.14mmol) and Pd(PPhs)2Cl2 (85.0mg, 0.12mmol) were added and the resulting mixture was stirred at rt under N2 overnight. The reaction mixture was allowed to cool to rt, filtered through a celite pad and concentrated. The residue was purified on silica (100% heptane to EtOAc:heptane, 1 :4) to give the title compound (577mg, 52%) as a pale yellow solid. UPLC (Method A) 3.30 min, 99.0 %, ES ⁺ : 256.1 [M+H] ⁺ . INTERMEDIATE 71

Methyl 4-pyrazol-1 -yl-3-[2-(3-pyridyl)ethynyl]benzoate

A RBF was charged with methyl 4-fluoro-3-[2-(3-pyridyl)ethynyl]benzoate (208mg, 0.81 mmol), CS2CO3 (797mg, 2.44mmol), pyrazole (56mg, 0.81 mmol) and DMF (15mL) and heated to 80°C for 0.5h under a N2 atmosphere. The reaction mixture was allowed to cool to rt, the solvent partially removed, the residue diluted with H2O (15mL) and EtOAc (20mL) and the layers separated. The aqueous layer was extracted with EtOAc (3x30mL), combined organics were dried over Na2SO4, filtered, and concentrated to give a beige solid. The residue was purified on silica (100% heptane to EtOAc:heptane, 3:7) to give the title compound (177mg, 65%) as a colourless solid. UPLC (Method A) 3.13 min, 91 %, ES ⁺ : 304.1 [M+H] ⁺ .

INTERMEDIATE 72

4-Pyrazol-1 -yl-3-[2-(3-pyridyl)ethynyl]benzoic acid

To a solution of Methyl 4-pyrazol-1-yl-3-[2-(3-pyridyl)ethynyl]benzoate (177mg, 0.58mmol) in THF:MeOH:Water (2.0mL:1 ,0mL:1 .OmL) was added UOH.H2O (40mg, 0.95mmol) and the mixture stirred at rt, under a N2 atmosphere, overnight. The reaction mixture was partially concentrated, H2O (5. OmL) added and the solution acidified using 2N HCI to pH 4. The resultant precipitate was collected on a frit and washed with MTBE (20mL), and dried to yield the title compound (149mg, 88%). UPLC (Method A) 1.74 min, 99.5 %, ES ⁺ : 290.1 [M+H] ⁺ .

INTERMEDIATE 73

3-lodo-4-methyl-benzoyl chloride

To 3-iodo-4-methyl-benzoic acid (1.81g, 6.91 mmol) at 0°C was added dropwise thionyl chloride (10.0mL, 138mmol). The mixture was stirred at 80°C under reflux for 2h. The volatile components were removed in vacuo and the residue was dissolved in toluene (10mL) then concentrated in vacuo to give the title compound (1.80g, 54%) as an off-white solid and used in the next step without further purification.

INTERMEDIATE 74

3-lodo-4-methyl-N-[4-[(4-methylpiperazin-1-yl)methyl]-3-

(trifluoromethyl)phenyl]benzamide

3-lodo-4-methylbenzoyl chloride (1.80g, 3.73mmol) was added to a solution of 4- [(4-methylpiperazin-1 -yl)methyl]-3-(trifluoromethyl)aniline (1 ,57g, 1 ,54mmol),

DIPEA (1 ,20mL, 6.89mmol), and DMAP (65.4mg, 0.54mmol) in THF (20mL). After stirring at rt for 3h, the reaction was quenched with H2O (50mL). EtOAc (50mL) was added and the layers separated. The aqueous layer was extracted with EtOAc (50mL) and the combined organic layers were concentrated. The resultant brown residue was purified on silica (5% MeOH saturated with NHs in DCM), giving the title compound (2.18g, quant.) as an off-white solid. UPLC (Method A) 3.92 min, 95.8 %, [M+H] ⁺ = 518.1. EXAMPLE 1

3-[2-(2-aminopyrimidin-5-yl)ethynyl]-N-(4,4-difluoro-6,7- dihydro-5H- pyrazolo[1,5-a]pyridin-2-yl)-4-methyl-benzamide

To a solution of 4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-amine (180mg, 1.04mmol) and methyl 3-[2-(2-aminopyrimidin-5-yl)ethynyl]-4-methyl- benzoate (320mg, 1 ,20mmol) in THF (20mL) was added KOtBu (20%w/w solution in THF, 2.45mL, 4.16mmol) dropwise and the mixture stirred at rt for 1 h. The reaction mixture was concentrated and H2O (~10mL) and TBME (~3.0mL) added. The suspension was sonicated and filtered and the off-white solid washed with ~2.0mL TBME and dried to give 218mg of off-white solid. This was purified on silica (Biotage Isolera, reverse phase, 50% to 65% THF in H2O, both eluents containing 0.1 Vol% NH3) to give the title compound (183mg, 43%) as a colourless solid after freeze-drying. UPLC (Method A) 2.99 min, 99.5 %, [M+H] ⁺ = 409.2.

EXAMPLE 2

5-[2-[5-[(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyri din-2-yl)carbamoyl]-

2-methyl-phenyl]ethynyl]-N,1 -dimethyl-imidazole-2-carboxamide

To a microwave vial was added N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5- a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (450mg, 1.21 mmol), 5-bromo-N,1- dimethyl-imidazole-2-carboxamide (290mg, 1.33mmol), DIPEA (0.63mL, 3.63mmol) and MeCN (15mL) and the resulting solution was degassed for 5min, before addition of Cui (31.6mg, 0.16mmol) and Pd(PPhs)2Cl2 (116mg, 0.16mmol), the vial capped and heated in microwave at 100°C for 1 h. Then reaction mixture was allowed to cool to rt, filtered through a celite pad and concentrated. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :9 to 4:1 , both eluents containing 0.1 Vol% NH3) to give the title compound (124mg, 23%) as a colourless solid. UPLC (Method C) 3.19 min, 100 %, [M+H] ⁺ = 453.2.

EXAMPLE 3

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-(2- pyrimidin-5-ylethynyl)benzamide

To a solution of methyl 4-methyl-3-(2-pyrimidin-5-ylethynyl)benzoate (216mg, 0.86mmol) and 4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-amine (135mg, 0.78mmol) in THF (4.0mL) was added KOtBu (20%w/w solution in THF, 1.73mL, 3.12mmol) dropwise and the mixture stirred at rt for 0.5h. The reaction mixture was quenched by addition of H2O (20mL) and stirred for 20 min affording an emulsion that was filtered (very slow filtration). The solid and the filtrate were combined and partitioned between 10% K2CO3 (20mL) and EtOAc (2x20mL). The combined organics were concentrated. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :4 to 100% MeCN, both eluents containing 0.1 Vol% NH3). Product fractions were concentrated and extracted with EtOAc (2x50mL). The combined organics were dried over MgSO4 and concentrated to give a brown oily residue. This was suspended in TBME (100mL) and washed with 10% citric acid solution (2x50mL), then washed with 10% K2CO3 solution (2x50mL). The TBME layer was dried over MgSO4 and concentrated to give a pale orange solid that was triturated with TBME (3.0mL) then TBME:MeOH (3.0mL, 5:1) to give the title compound (59.4mg,19%) as a pale yellow solid. UPLC (Method A) 3.15 min, 98.6 %, [M+H] ⁺ = 394.2. EXAMPLE 4

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-[5-

(triazol-2-yl)-3-pyridyl]ethynyl]benzamide

A mixture of 3-bromo-5-(triazol-2-yl)pyridine (50.0mg, 0.22mmol), N-(4,4-difluoro- 6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (70.0mg, 0.22mmol), Cui (2.11 mg, O.OI mmol), Pd(PPhs)2Cl2 (7.81 mg, O.OI mmol) and DIPEA (0.12mL, 0.67mmol) in MeCN (5.0mL) was sparged with nitrogen for 2 min. The mixture was then heated at 80°C for 3h. On cooling, the crude mixture was purified on silica (EtOAc:heptane, 1 :4 to 4:1) to give the title compound as a semi-solid which was dissolved in MeCN (2.0mL) followed by H2O (1.5mL). The resulting suspension was dried overnight to yield the title compound (50.0mg, 49%) as a white solid. UPLC (Method C) 3.58 min, 100 %, [M+H] ⁺ = 460.2.

EXAMPLE 5

3-[2-(6-amino-3-pyridyl)ethynyl]-N-(4,4-difluoro-6,7-dihy dro-5H- pyrazolo[1,5-a]pyridin-2-yl)-4-methyl-benzamide

To a solution of methyl 3-[2-(6-amino-3-pyridyl)ethynyl]-4-methyl-benzoate (96.1 mg, 0.36mmol) and 4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2- amine (50.0mg, 0.29mmol) in THF (1.0mL) was added KOtBu (20%w/w solution in THF, 0.64mL, 1.16mmol) dropwise and the mixture stirred at rt for 0.5h. The reaction mixture was quenched by addition of H2O (10mL) and the resulting suspension extracted with EtOAc (2x15mL). The combined organics were washed with 10% K2CO3 solution (15mL), dried over MgSO4 and concentrated to give a pale yellow oily residue. This was triturated with MeCN, filtered and dried to give the title compound (49.2mg, 40%) as an off-white solid. UPLC (Method A) 3.15 min, 96.4 %, [M+H] ⁺ = 408.2.

EXAMPLE 6

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-[2- (methylamino)pyrimidin-5-yl]ethynyl]benzamide

Cui, XPhos

To 5-bromo-N-methylpyrimidin-2-amine (62.6mg, 0.33mmol), CS2CO3 (217mg, 0.67mmol), Cui (2.1 mg, O.OI mmol) and XPhos Pd G3 (11.3mg, O.OI mmol) in 1 ,4- dioxane (3.5mL) was added N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5- a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (70.0mg, 0.22mmol). The mixture was degassed and heated to 80°C under nitrogen for 16h. Saturated EDTA solution (3.5mL) was added and the mixture stirred for 3h before extraction with EtOAc (2x3.5mL). Combined organics were washed with brine (3.5mL) and H2O (3.5mL), dried over MgSO4 and then concentrated. The residue was purified on silica (Biotage Isolera, normal phase, 100% EtOAc to MeOH:EtOAc, 1 :9) to afford partially pure material. The residue was further purified on silica (Biotage Isolera, reverse phase, 12% to 100% MeCN in H2O, both eluents containing 0.1 Vol% NH3). The resulting product was lyophilised overnight to yield the title compound (13.4mg, 14%) as a colourless solid. UPLC (Method A) 3.23 min, 98.6 %, [M+H] ⁺ = 423.2. EXAMPLE 7

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-[6-

(methylamino)-3-pyridyl]ethynyl]benzamide

To a microwave vial 5-bromo-N-methyl-pyridin-2-amine (180mg, 0.96mmol), N- (4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl-4-methyl- benzamide (53.0mg, 0.17mmol), Cui (6.0mg, 0.03mmol), PdCl2(PPhs)2 (14.0mg, 0.02mmol) and degassed MeCN (4.0mL) were added and the resulting mixture was degassed for 5min before addition of DIPEA (0.09mL, 0.52mmol) and the mixture heated in the microwave at 100°C for 1 h. Then reaction mixture was allowed to cool to rt, filtered through a celite pad and concentrated. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :9 to 7:3, both eluents containing 0.1 Vol% HCO2H) to give a semi-pure white powder. The powder was further purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :9 to 7:3, both eluents containing 0.1 Vol% NH3) to give the title compound (4.80mg, 6%). UPLC (Method A) 3.32 min, 95.7 %, [M+H] ⁺ = 422.2.

EXAMPLE 8

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-[2-[6-

(difluoromethyl)-3-pyridyl]ethynyl]-4-methyl-benzamide

To a MW vial was added N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2- yl)-3-ethynyl-4-methyl-benzamide (60.0mg, 0.19mmol), 5-bromo-2-

(difluoromethyl)pyridine (39.6mg, 0.19mmol), MeCN (2.0mL) and DIPEA (99.4pL, 0.57mmol). The reaction mixture was degassed using nitrogen, Cui (1.8mg, 0.01 mmol) and PdCl2(PPhs)2 (6.7mg, 0.01 mmol) were added and the reaction was heated under MW irradiation for 60min at 100°C. The reaction was concentrated in vacuo. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :9 to 4:1 , both eluents containing 0.1 Vol% NHs). The residue was further purified via SCX column (1g; compound loaded with MeOH/DCM 1 :1 mixture, eluted with NHs/MeOH). The residue was further purified via crystallisation from a DCM/heptane mixture (1 :1 , 5mL, compound dissolved in the mixture and solvents left for slow evaporation). The solid was filtered off, washed with TBME (20mL) and left to dry on the sinter funnel overnight. The title compound was obtained (15.6mg, 18%) as a beige solid. UPLC (Method C) 3.48 min, 97.9 %, [M+H] ⁺ = 443.2.

EXAMPLE 9

5-[2-[5-[(3-Ethyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1, 5-a]pyridin-2- yl)carbamoyl]-2-methyl-phenyl]ethynyl]-N,1-dimethyl-imidazol e-2- carboxamide

To a solution of methyl 4-methyl-3-[2-[3-methyl-2-(methylcarbamoyl)imidazol-4- yl]ethynyl]benzoate (49.4mg, 0.16mmol) and 3-ethyl-4,4-difluoro-6,7-dihydro-5H- pyrazolo[1 ,5-a]pyridin-2-amine (29.0mg, 0.14mmol) in THF (10mL) was added KOtBu (1.7M solution in THF, 0.34mL, 0.58mmol) dropwise and the mixture stirred at rt overnight. Another portion of KOtBu (1.7M solution in THF, 0.17mL, 0.29mmol) was added dropwise and the reaction was stirred at rt for 1 h. Water (10mL) was added and the reaction was stirred for 2 days. To the reaction mixture was added H2O (10mL) and the mixture extracted with DCM (3x1 OmL). Combined organics were washed with brine (10mL), dried over Na2SO4 and concentrated to provide the crude product. The crude was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :4 to 4:1 , both eluents containing 0.1 Vol% NH3). The fractions were concentrated and freeze-dried to yield the title compound (12.3mg, 18%) as a colourless solid. UPLC (Method A) 3.24 min, 100%, [M+H] ⁺ = 481.2.

EXAMPLE 10

N-(3-ethyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyr idin-2-yl)-4-methyl-

3-[2-[2-(methylamino)pyrimidin-5-yl]ethynyl]benzamide

To a solution of methyl 4-methyl-3-[2-[2-(methylamino)pyrimidin-5- yl]ethynyl]benzoate (40.0mg, 0.14mmol) and 3-ethyl-4,4-difluoro-6,7-dihydro-5H- pyrazolo[1 ,5-a]pyridin-2-amine (29.0mg, 0.14mmol) in THF (10mL) was added KOtBu (1.7M solution in THF, 0.33mL, 0.57mmol) dropwise and the mixture stirred at rt for 1 h. The reaction was quenched with H2O (10mL) and extracted with DCM (3x1 OmL). Combined organics were washed with brine (10mL), dried over Na2SO4 and concentrated to provide the crude product. This was further purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :4 to 4:1 , both eluents containing 0.1 Vol% NH3). The fractions were concentrated and freeze- dried to yield the title compound (19.6mg, 31 %) as a colourless solid. UPLC (Method A) 3.30 min, 100%, [M+H] ⁺ = 451.2.

EXAMPLE 11

N-(3-cyclopropyl-4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5 -a]pyridin-2-yl)-4- methyl-3-[2-[2-(methylamino)pyrimidin-5-yl]ethynyl]benzamide

To a solution of methyl 4-methyl-3-[2-[2-(methylamino)pyrimidin-5- yl]ethynyl]benzoate (49.7mg, 0.18mmol) and 3-cyclopropyl-4,4-difluoro-6,7- dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-amine (29.0mg, 0.14mmol) in THF (7.0mL) was added KOtBu (1.7M solution in THF, 0.32mL, 0.54mmol) dropwise and the mixture stirred at rt for 1 h. The reaction was quenched with H2O (10mL) and extracted with DCM (3x1 OmL). Combined organics were washed with brine (10mL), dried over Na2SO4 and concentrated to provide the crude product. The crude was further purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :4 to 4:1 , both eluents containing 0.1 Vol% NH3). The fractions were concentrated and freeze-dried to yield the title compound (23.7mg, 38%) as a colourless solid. UPLC (Method A) 3.27 min, 100%, [M+H] ⁺ = 463.3.

EXAMPLE 12

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-(5- pyrazol-1-yl-3-pyridyl)ethynyl]benzamide

A mixture of 3-bromo-5-pyrazol-1-yl-pyridine (64.0mg, 0.29mmol), N-(4,4-difluoro- 6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (90.0mg, 0.29mmol), DIPEA (0.15mL, 0.86mmol), Cui (2.7mg, 0.01 mmol) and Pd(PPhs)2Cl2 (10.Omg, 0.01 mmol) in MeCN (2.0mL) was degassed under nitrogen for 1 min in a microwave reaction vial. It was then irradiated in microwave at 100°C for 1 h. The crude mixture was purified on silica (NH3 in MeOH (7N):DCM, 1 :99 to 1 :19) to yield the title compound (53.0mg, 40%) as a white solid. UPLC (Method C) 3.43 min, 98.3%, [M+H] ⁺ = 459.2.

EXAMPLE 13

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-[2-(5-fluoro-3- pyridyl)ethynyl]-4-methyl-benzamide

To a solution of 3-bromo-5-fluoropyridine (97.7mg, 0.56mmol) in DMF (1.5mL) and EtsN (0.25mL, 1.79mmol), at rt and under N2, was added Cui (2.1 mg, 0.01 mmol) and PdCl2(PPhs)2 (7.8mg, 0.01 mmol). The solution was purged with N2 (x3) and N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl- 4-methyl-benzamide (70.0mg, 0.22mmol) was added. The resulting solution was then heated at 80°C for 1 h. The reaction mixture was cooled down and left to stand at rt for 18h. The reaction mixture was concentrated in vacuo and the crude was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 9:11 to 100% MeCN, both eluents containing 0.1 Vol% NH3). The residue was then recrystallised from a hot mixture of MeOH:H2O (10mL, 1 :1) and filtered to afford the desired product. The filtrate, rich in product, was concentrated to remove MeOH and the resulting aqueous was freeze dried. The freeze dried residue gave a second batch of the desired product. The two batches were combined and ground togetherwith a spatula to afford the title compound (58.9mg, 64%) as a colourless solid. UPLC (Method A) 3.51 min, 99.3%, [M+H] ⁺ = 411 .2. EXAMPLE 14

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-(2-furo[3,2- b]pyridin-6-ylethynyl)-4-methyl-benzamide

To a solution of 6-bromofuro[3,2-b]pyridine (101 mg, 0.51 mmol) in DMF (1.5mL) and EtsN (0.25mL, 1.79mmol), at rt and under N2, were added PdCl2(PPhs)2 (7.8mg, O.OI mmol) and Cui (2.1 mg, O.OI mmol). The resulting mixture was purged three times with N2 prior to the addition of N-(4,4- difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl-4-methyl- benzamide (70.0mg, 0.22mmol). The resulting solution was then heated up to 80°C for 1 h. The reaction mixture was cooled to rt and left standing for 18h at rt. The volatiles were removed in vacuo and the residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 2:3 to 100% MeCN, both eluents containing 0.1 Vol% NH3). The residue was freeze dried overnight to yield the title compound (55.1 mg, 57%) as a colourless solid. UPLC (Method A) 3.51 min, 99.7%, [M+H] ⁺ = 433.2.

EXAMPLE 15

3-[2-(2-amino-3-pyridyl)ethynyl]-N-(4,4-difluoro-6,7-dihy dro-5H- pyrazolo[1,5-a]pyridin-2-yl)-4-methyl-benzamide

A solution of N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3- ethynyl-4-methyl-benzamide (100mg, 0.32mmol), 3-bromopyridin-2-amine (54.9mg, 0.32mmol) and DIPEA (166pL, 0.95mmol) in MeCN (1.5mL) was degassed in a MW vial. Cui (3.0mg, 0.02mmol) and PdCl2(PPhs)2 (11.2mg, 0.02mmol) were added, the vial was capped, and the reaction was heated in the microwave reactor at 100°C for 40min. The reaction was filtered through dicalite and concentrated to give a brown oil. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 3:7 to 4:1 , both eluents containing 0.1 Vol% NH3) to give the title compound (66.3mg, 51 %) as a pale yellow solid after freeze drying. UPLC (Method A) 3.25 min, 98.9%, [M+H] ⁺ = 408.2.

EXAMPLE 16

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-

(1 ,6-naphthyridin-3-yl)ethynyl]benzamide

A solution of 3-bromo-1 ,6-naphthyridine (41.8mg, 0.20mmol), N-(4,4-difluoro-6,7- dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (63.0mg, 0.20mmol) and DIPEA (0.1 OmL, 0.60mmol) in MeCN (2.0mL) was degassed by bubbling N2 through for 10min. Cui (1.9mg, O.OI mmol) and PdCl2(PPhs)2 (7.0mg, 0.01 mmol) were then added and the reaction was heated in the microwave reactor at 100°C for 1 h. The reaction mixture was concentrated and the residue purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 2:3 to 4:1 , both eluents containing 0.1 Vol% NH3). Fractions were combined, concentrated and freeze-dried to give the title compound (17.0mg, 19%) as a white solid. LCMS (Method B) 2.66 min, 99.3%, [M+H] ⁺ = 444.0. EXAMPLE 17

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-[2-(4- methoxypyrimidin-5-yl)ethynyl]-4-methyl-benzamide

In a microwave vial a solution of N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5- a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (70.0mg, 0.22mmol), 5- bromopyrimidin-2-amine (42.0mg, 0.22mmol) and DIPEA (0.12mL, 0.67mmol) in MeCN (1.1 mL) was de-gassed for 2 min before treatment with Cui (2.1 mg, 0.01 mmol) and Pd(PhsP)2Cl2 (7.8mg, 0.01 mmol) and the vial sealed and heated to 100°C by microwave irradiation for 1 h. The reaction was concentrated in vacuo and the crude material purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :19 to 19:1 , both eluents containing 0.1 Vol% NHs) to afford the title compound (18.9mg, 20%) as a colourless solid. UPLC (Method A) 3.53 min, 99.3%, [M+H] ⁺ = 424.2.

EXAMPLE 18

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-[2-(5-methoxy-

3-pyridyl)ethynyl]-4-methyl-benzamide

In a microwave vial a solution of N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5- a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (90.0mg, 0.29mmol), 3-bromo-5- methoxypyridine (53.7mg, 0.29mmol) and DIPEA (0.15mL, 0.86mmol) in MeCN (1.0mL) was de-gassed for 2min before treatment with Cui (2.7mg, 0.01 mmol) and Pd(PhsP)2Cl2 (10.0mg, 0.01 mmol), the vial sealed and the reaction heated to 100°C by microwave irradiation for 1 h. The reaction was concentrated in vacuo and the residue purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :19 to 100% MeCN, both eluents containing 0.1 Vol% NH3) to afford the title compound (28.9mg, 23%) as a white solid. UPLC (Method A) 3.40 min, 95.5%, [M+H] ⁺ = 423.2.

EXAMPLE 19

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-(5- methyl-3-pyridyl)ethynyl]benzamide

To a solution of methyl 4-methyl-3-[2-(5-methyl-3-pyridyl)ethynyl]benzoate (115mg, 0.43mmol) and 4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2- amine (60mg, 0.35mmol) in THF (2.0mL) was added KOtBu (20%w/w solution in THF, 0.77mL, 1.39mmol) dropwise and the mixture stirred at rt for 0.5h. The reaction mixture was quenched by addition of H2O (10mL) and the resulting suspension extracted with EtOAc (2x15mL). The combined organics were washed with 10% K2CO3 solution (15mL), dried over MgSO4 and concentrated to give a clear oily residue. This was triturated with MeCN (~1.0mL with sonication), filtered and dried to give the title compound (53.3mg, 38%) as a colourless solid. UPLC (Method A) 3.45 min, 99.6%, [M+H] ⁺ = 407.3.

EXAMPLE 20

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-[2-[5-[3-

(dimethylamino)pyrrolidin-1-yl]-3-pyridyl]ethynyl]-4-meth yl-benzamide To methyl 3-[2-[5-[3-(dimethylamino)pyrrolidin-1-yl]-3-pyridyl]ethynyl ]-4-methyl- benzoate (158mg, 0.34mmol) and 4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5- a]pyridin-2-amine (49mg, 0.28mmol) dissolved in THF (5.0mL) was added tertbutoxypotassium (20% w/w in THF) (0.68mL, 1 .13mmol) dropwise over 5min. The reaction was stirred for 3h and the resulting precipitate filtered, washed with THF (2x5. OmL) and dried to afford the crude product. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :4 to 4:1 , both eluents containing 0.1 Vol% NH3) to afford the title compound (30.7mg, 21 %) as a colourless solid. UPLC (Method A) 3.38 min, 96.7%, [M+H] ⁺ = 505.3.

EXAMPLE 21

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-3-[2-[5-(2- ethylazetidin-1-yl)-3-pyridyl]ethynyl]-4-methyl-benzamide

To a degassed solution of 3-[2-(5-bromo-3-pyridyl)ethynyl]-N-(4,4-difluoro-6,7- dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-benzamide (32.0mg,

0.07mmol), Pd2(dba)s (4.4mg, 4.80pmol), XantPhos (5.5mg,

0.01 mmol), NaO‘Bu (27.5mg, 0.29mmol) in 1 ,4-dioxane (5. OmL) was added 2- ethylazetidine hydrochloride (11.6mg, O.IOmmol). The reaction mixture was heated to 100°C for 3h. The mixture was diluted with H2O (10mL) and extracted with EtOAc (3x1 OmL). Combined organics were washed with H2O (3x1 OmL), brine (10mL), dried over Na2SO4 and concentrated in vacuo to provide the crude product. The crude was further purified on silica (MeOH (0.1 % NHs):DCM, 1 :49 to 1 :19) and the fractions containing the product were concentrated and freeze dried to provide the title compound (11.6mg, 24%) as a pale yellow solid. LCMS (Method B) 3.62 min, 93.3%, [M+H] ⁺ = 476.4. EXAMPLE 22

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-[5-

(2-methylazetidin-1-yl)-3-pyridyl]ethynyl]benzamide

To a degassed solution of 3-bromo-5-(2-methylazetidin-1-yl)pyridine (48.0mg, 0.21 mmol), DIPEA (0.10mL, 0.57mmol), Pd(PPh ₃ )2CI ₂ (6.7mg, O.OI mmol) and Cui (1.8mg, O.OI mmol) in MeCN (2.0mL) was added N-(4,4-difluoro-6,7-dihydro- 5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl-4-methyl-benzamide (60.0mg,

0.19mmol). The reaction mixture was then heated to 100°C for 1 h under microwave irradiation. The reaction mixture was then filtered through a celite pad and concentrated in vacuo to obtain the crude. The residue was purified by column chromatography (Biotage Isolera, reverse phase, MeCNiHLO, 3:7 to 100% MeCN, both eluents containing 0.1 Vol% NH3) to obtain the title compound (12.3mg, 14%) as an off-white solid. UPLC (Method C) 3.13 min, 96.5%, [M+H] ⁺ = 462.3.

EXAMPLE 23

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-[5-

(1-methylpyrrolidin-3-yl)-3-pyridyl]ethynyl]benzamide

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-4-methyl-3-[2-(5- pyrrolidin-3-yl-3-pyridyl)ethynyl]benzamide dihydrochloride (20.0mg, 0.04mmol) was dissolved in DCM (5.0mL) and washed with K2CO3 (sat. aq. 5.0mL). The organic was collected and the aqueous extracted with DCM (2 x 5.0mL). The combined organic extracts were dried over Na2SO4 and concentrated to a yellow oil. The residue was dissolved in a solution of formic acid (0.5mL) and formaldehyde (1.0mL). The resultant mixture was heated to 70°C for 4h. The reaction mixture was concentrated in vacuo. The residue was dissolved in H2O (3.0mL) and basified to pH=12 by the addition of NaOH (2.0M aq.). The precipitate was extracted with DCM (3x5. OmL). The extracts were combined, dried over Na2SO4 and concentrated. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 2:3 to 4:1 , both eluents containing 0.1 Vol% NHs). The relevant fractions were combined and freeze-dried to yield the title compound (5.0mg, 25%) as an off-white solid. LCMS (Method B) 2.47 min, 89.3%, [M+H] ⁺ = 476.3.

EXAMPLE 24

N-(4,4-difluoro-6,7-dihydro-5H-pyrazolo[1,5-a]pyridin-2-y l)-4-methyl-3-[2-[5-

[2-(trifluoromethyl)azetidin-1-yl]-3-pyridyl]ethynyl]benz amide

To a degassed solution of 3-bromo-5-[2-(trifluoromethyl)azetidin-1-yl]pyridine (52.0mg, 0.19mmol), DIPEA (0.10mL, 0.56mmol), Pd(PPh ₃ )2CI ₂ (6.5mg, 0.01 mmol) and Cui (1.8mg, 0.01 mmol) in MeCN (2. OmL) was added N-(4,4- difluoro-6,7-dihydro-5H-pyrazolo[1 ,5-a]pyridin-2-yl)-3-ethynyl-4-methyl- benzamide (64.2mg, 0.20mmol). The reaction mixture was then heated to 100°C for 1h under microwave irradiation. The reaction mixture was then filtered through a celite pad and concentrated in vacuo to obtain the crude. The residue was purified on silica (Biotage Isolera, reverse phase, MeCN:H2O, 1 :1 to 9:1 , both eluents containing 0.1 Vol% NH3) to afford the title compound (26.0mg, 27%) as a colourless solid. UPLC (Method A) 3.67 min, 100%, [M+H] ⁺ = 516.2. EXAMPLE 25

N-(5,5-Dimethyl-6,8-dihydroimidazo[2,1-c][1,4]oxazin-2-yl )-4-methyl-3-[2-[6-

(methylamino)-3-pyridyl]ethynyl]benzamide

To a MW vial was added DIPEA (0.6mL, 3.44mmol), 5-bromo-N-methyl-pyridin-2- amine (28mg, 1.51 mmol), N-(5,5-dimethyl-6,8-dihydroimidazo[2,1-c][1 ,4]oxazin- 2-yl)-3-ethynyl-4-methyl-benzamide (350mg, 1.13mmol) and MeCN (10mL). The reaction mixture was degassed using nitrogen, Cui (12.0mg, 0.06mmol) and PdCl2(PPhs)2 (40.0mg, 0.06mmol) were added and reaction was heated under MW irradiation for 60min at 100°C. The reaction was filtered through celite and concentrated in vacuo. The residue was purified on silica (Biotage Isolera, reverse phase, THF:H20, 1 :4 to 3:2, both eluents containing 0.1 Vol% NH3) to give the title compound (119mg, 25%) as a pale yellow solid post-freeze drying. UPLC (Method A) 3.07 min, 100%, [M+H] ⁺ = 416.3.

COMPARATIVE EXAMPLE 1

3-(imidazo[1,2-b]pyridazin-3-ylethynyl)-4-methyl-N-[4-[(4 -methyl-1- piperazinyl)methyl]-3-(trifluoromethyl)phenyl]benzamide (Ponatinib, CAS: 943319-70-8)

Ponatinib was purchased commercially from AK Scientific, Inc. COMPARATIVE EXAMPLE 2

4-methyl-N-[3-(4-methylimidazol-1-yl)-5-(trifluoromethyl) phenyl]-3-[(4- pyridin-3-ylpyrimidin-2-yl)amino]benzamide (Nilotinib, CAS: 641571-10-0)

Nilotinib was purchased commercially from Medchem Tronica.

COMPARATIVE EXAMPLE 3

3-[2-(3-Amino-6-fluoro-4-isoquinolyl)ethynyl]-4-methyl-N- [1-(2- morpholinoethyl)pyrazol-3-yl]benzamide

6-Fluoro-4-iodo-isoquinolin-3-amine (185.0mg, 0.59mmol, 91.7% pure), 3- ethynyl-4-methyl-N-[1-(2-morpholinoethyl)pyrazol-3-yl]benzam ide (160.0mg, 0.45mmol, 96% pure), EtsN (75.9pL, 0.54mmol), Pd(PPhs)2Cl2 (8.0mg, 11.3pmol) and Cui (3.0mg, 15.9pmol) were added to MeCN (5.0mL) and the reaction heated under reflux at 82°C for3h. The mixture was filtered through Celite and concentrated in vacuo. The residue was purified by reverse phase HPLC (ACE-5AQ, 100 x 21.2mm, 5pm, 25mL per min, gradient 0% to 100% (over 7min) then 100% (3 min) MeOH in 10% MeOH/IYO). The residue was then repurified by reverse phase HPLC (Phenomenex Synergi Hydro-RP 80A AXIA, 100 x 21.2mm, 4pm, 25mL per min, gradient 20% to 100% (over 7 min) then 100% (3 min) MeOH in 10% MeOH/H2O) [1% formic acid]). The material was de-salted by treating with sat. aq. NaHCOs and extracted into DCM and concentrated in vacuo. The residue was then repurified by reverse phase HPLC (ACE-5AQ, 100 x 21.2mm, 5pm, 25mL per min, gradient 0 % to 100 % (over 7 min) then 100% (3 min) MeOH in 10% MeOH/H2O) then dried in a vacuum oven at 50°C overnight to give the title compound (15.5mg, 6.8%) as a yellow solid. LC-MS (Method H) 4.57 min, 98 %, [M+H] ⁺ = 498.5.

COMPARATIVE EXAMPLE 4

N-[3,3-difluoro-1-(4-methylpiperazin-1-yl)indan-5-yl]-3-( 2-imidazo[1,2- b]pyridazin-3-ylethynyl)-4-methyl-benzamide

To a solution of 3,3-difluoro-1-(4-methylpiperazin-1-yl)indan-5-amine (80mg, 0.30mmol) and 3-(2-lmidazo[1 ,2-b]pyridazin-3-ylethynyl)-4-methyl-benzoic acid (119mg, 0.30mmol, 70% purity) in 2-MeTHF (10mL) and DMF (5mL) was added pyridine (100pL, 1.20mmol) followed 1-propylphosphonic acid cyclic anhydride (400pL, 0.60mmol). The reaction mixture was then heated at 70°C overnight. Separately, to a solution of 3,3-difluoro-1-(4-methylpiperazin-1-yl)indan-5-amine (23mg, 0.09mmol) and 3-(2-lmidazo[1 ,2-b]pyridazin-3-ylethynyl)-4-methyl- benzoic acid (34mg, 0.09mmol, 70 % purity) in 2-MeTHF (3mL) and DMF (1 mL) was added pyridine (30pL, 0.34mmol) followed 1-propylphosphonic acid cyclic anhydride (100pL, 0.17mmol). The reaction mixture was then heated at 70°C overnight. The two reactions were then cooled to rt and combined. To the resulting mixture was added EtOAc (50mL), followed by aq. K2CO3 (2M, 50mL) and the phases separated. The aqueous phase was extracted with EtOAc (2x50 mL) and combined organics were washed with brine (50mL), dried (Na2SO4) and concentrated in vacuo to give the crude product as a brown oil. The crude product was purified on silica (DCM:NHs (7M in MeOH), 99:1 to 95:5), further purified on silica (acetone:DCM, 1 :9 to 1 :4) and repurified on silica (Biotage Isolera, reverse phase, THF:H2O, 1 :9 to 4:1 , both eluents containing 0.1 Vol% NH3) and the material freeze-dried for 72h to yield the title compound (26mg, 13%) as an off white solid. UPLC (Method A) 3.24 min, 99.5 %, [M+H] ⁺ = 527.3. COMPARATIVE EXAMPLE 5

N-[6-(4-isopropyl-1,2,4-triazol-3-yl)-2-pyridyl]-3-[2-(3- pyridyl)ethynyl]benzamide

To a mixture of 6-(4-lsopropyl-1 ,2,4-triazol-3-yl)pyridin-2-amine (50mg, 0.25mmol) and triethylamine (40pL, 0.32mmol) in DCM (3.0mL), a solution of 3- [2-(3-pyridyl)ethynyl]benzoyl chloride (119mg, 0.49mmol) in DCM (2.0mL) was added dropwise and the reaction mixture was stirred at rt overnight under nitrogen. The reaction mixture was quenched with H2O (10mL) and extracted with DCM (3x10 mL). The combined organics were washed with brine (15mL), dried over Na2SO4 and concentrated in vacuo. The residue was purified on silica (Biotage Isolera, reverse phase, 20% to 80% MeCN in H2O both eluents containing 0.1 Vol% NH3), to give the title compound (8.0mg, 7.9%) as an off-white solid. UPLC (Method A) 2.97 min, 99.3 %, ES ⁺ : 409.3 [M+H] ⁺ .

COMPARATIVE EXAMPLE 6

N-(5-ethyl-1,3,4-thiadiazol-2-yl)-4-pyrazol-1-yl-3-[2-(3- pyridyl)ethynyl]benzamide

To a solution of 4-pyrazol-1-yl-3-[2-(3-pyridyl)ethynyl]benzoic acid (79.0mg, 0.25mmol) and 2-amino-5-ethyl-1 ,3,4-thiadiazole (38.0mg, 0.29mmol) in DMF (2.0mL) was added HATU (120. Omg, 0.32mmol) and triethylamine (0.10mL, 0.72mmol) under a N2 atmosphere and the reaction stirred at rt overnight. The reaction was quenched with sat. aq. NaHCOs (10 mL) and diluted with EtOAc (30mL), the phases separated and the aqueous extracted with EtOAc (3x30mL). The combined organics were dried over Na2SO4, filtered and concentrated. The crude material was purified by cationic exchange resin SCX-2 (washed with MeOH and eluted with NH3 (2M in MeOH)). The resulting solid was triturated from H2O:MBTE, collected on a frit and dried to give the title compound (41 mg, 41 %) as an off-white solid. UPLC (Method A) 2.02 min, 98.9 %, ES ⁺ : 401.2 [M+H] ⁺ .

COMPARATIVE EXAMPLE 7

4-Methyl-N-[4-[(4-methylpiperazin-1-yl)methyl]-3-(trifluo romethyl)phenyl]-3-

(2-pyrimidin-5-ylethynyl)benzamide

3-lodo-4-methyl-N-[4-[(4-methylpiperazin-1-yl)methyl]-3- (trifluoromethyl)phenyl]benzamide (422mg, 0.82mmol), 5-ethynylpyrimidine (90mg, 1.06mmol), PdCl2(PPhs)2 (33.2mg, 0.06mmol), Cui (16.4mg, 0.09mmol) and DIPEA (1.60mL, 9.19mmol) were dissolved in DMF (5.0mL) and the reaction was stirred at 80°C for 1 h under microwave irradiation. The mixture was quenched with H2O (30mL) and extracted with EtOAc (2x30mL). The combined organic layer was dried over Na2SO4, filtered, concentrated, and the resulting residue purified on silica (2-5% saturated NH3 solution in MeOH in DCM) to give the product as an off-white solid. The solid was triturated with 5% MeCN in heptane to give the title compound (117mg, 28%) as a colourless solid. LCMS (Method B) 3.02 min, 95.3 %, ES ⁺ : 494.6 [M+H] ⁺ . High Resolution Mass Spectrometry Data

*Calculated MIM assumes detection of protonated and deprotonated species in positive and negative ion mode respectively. BIOLOGICAL DATA

Ba/F3 Cell Titer Gio Assay

The CellTiter-Glo luminescent cell viability assay is a homogeneous method of determining the number of viable cells in culture based on quantification of the ATP present. Briefly, IL-3 dependent Ba/F3 cells are modified to express BCR- ABL. Activity of the transformed kinase overrides IL-3 dependency for cellular proliferation and survival. Test compounds that specifically inhibit kinase activity lead to programmed cell death which can be measured through the addition of CellTiter-Glo reagent. In this assay Ba/F3 cells expressing BCR-ABL (Advanced Cellular Dynamics) or parental Ba/F3 (control) cells were prepared at 5x10 ⁴ /mL in RPMI 1640 containing 10% FBS, 1 x Glutamax and 750ng/mL puromycin. Test compounds were dispensed into 384 well plates using the Tecan D300e at a top final assay concentration of 10pM with dosing normalised to 0.1 % DMSO in 50pL volume. 50pL cells were added to each well of the prepared 384 well plates and the plates spun at OOrpm for 1 min prior to incubation at 37°C, 5% CO2 for 48h. After 48h 15pL CellTiterGlo reagent was added to each well in the plate. Following a 60 min incubation at rt luminescence was read on the Pherastar FS reader.

The exemplified compounds of the invention were tested in the Ba/F3 CellTiterGlo Assay and the pICso data is shown in the table below. pICso data are calculated as the -logio(ICso in Molar). Those data show that the compounds of the invention can inhibit c-Abl.

MDR1 and BCRP-MDCK: effective efflux ratio

Wild-type MDCK, MDR1-MDCK and BCRP-MDCK cells were seeded into 24 well Transwell plates and cultured for 3 days to form monolayers. Test compound were prepared at 1 M in Hanks’ Balanced Salt Solution containing 25 mM HEPES and loaded into the donor compartments of Transwell plates bearing the cell monolayers (pH 7.4 for both donor and receiver compartments). Lucifer Yellow was added to the apical buffer in all wells to assess integrity of the cell monolayer. Duplicate wells were prepared and incubated at 37°C in a CO2 incubator. Samples were removed at time zero and 60 min and test compound analysed by LC- MS/MS. Concentrations of Lucifer Yellow in the samples was measured using a fluorescence plate reader. The apparent permeability (Papp) values of test compound was determined for both the apical to basal (A>B) and basal to apical (B>A) permeation and the efflux ratio (B>A: A>B) determined in each cell line. The effective efflux ratio was determined from the ratio of either M DR 1 -MDCK cells or BCRP-MDCK cells relative to the ratio observed in wild-type cells. A higher value represent a better substrate for the efflux mechanism, which is less preferable. These data show that the compounds of the invention are poor substrates for the efflux mechanisms.