Substituted pyrazolo[1,5-A]pyridine compounds as RET kinase inhibitors

Patent metadata

Field	Value
Publication number	US-10112942-B2
Application number	US-201715858240-A
Country	US
Kind code	B2
Filing date	Dec 29, 2017
Priority date	Oct 10, 2016
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

Provided herein are compounds of the Formula I:

and stereoisomers and pharmaceutically acceptable salts or solvates thereof, in which A, B, X 1 , X 2 , X 3 , X 4 , Ring D, and E have the meanings given in the specification, which are inhibitors of RET kinase and are useful in the treatment and prevention of diseases which can be treated with a RET kinase inhibitor, including RET-associated diseases and disorders.

First claim

What is claimed is:

1. A compound of the Formula I:

and pharmaceutically acceptable salts and solvates thereof, wherein:
X 1 , X 2 , X 3 and X 4 are independently CH or N, wherein zero, one or two of X 1 , X 2 , X 3 and X 4 is N;
A is CN;
B is
(b) C1-C6 alkyl optionally substituted with 1-3 fluoros,
(c) hydroxyC2-C6 alkyl-, wherein the alkyl portion is optionally substituted with 1-3 fluoros or a C3-C6 cycloalkylidene ring,
(e) (C1-C6 alkoxy)C1-C6 alkyl- optionally substituted with 1-3 fluoros,
(f) (R 1 R 2 N)C1-C6 alkyl-, wherein said alkyl portion is optionally substituted with OH and wherein R 1 and R 2 are independently H or C1-C6 alkyl (optionally substituted with 1-3 fluoros);
(g) hetAr 1 C1-C3 alkyl-, wherein hetAr 1 is a 5-6 membered heteroaryl ring having 1-3 ring heteroatoms independently selected from N, O and S and is optionally substituted with one or more independently selected C1-C6 alkyl substituents; or
(i) (hetCyc a )C1-C3 alkyl-,
hetCyc a - is a 4-6 membered heterocyclic ring having 1-2 ring heteroatoms independently selected from N and O and optionally substituted with one or more substituents independently selected from OH, C1-C6 alkyl (optionally substituted with 1-3 fluoros), hydroxyC1-C6 alkyl-, C1-C6 alkoxy, (C1-C6 alkyl)C(═O)—, (C1-C6 alkoxy)C1-C6 alkyl- and fluoro, or wherein hetCyc a is substituted with oxo;
Ring D is (i) a saturated 4-7 membered heterocyclic ring having two ring nitrogen atoms, or (ii) a saturated 7-9 membered bridged heterocyclic ring having two ring nitrogen atoms and optionally having a third ring heteroatom which is oxygen, wherein each of said rings is optionally substituted with (a) one to four groups independently selected from halogen, OH, C1-C3 alkyl which is optionally substituted with 1-3 fluoros, or C1-C3 alkoxy which is optionally substituted with 1-3 fluoros, (b) a C3-C6 cycloalkylidene ring, or (c) an oxo group;
E is
(h) Ar 1 C1-C6 alkyl-,
(j) hetAr 2 C1-C6 alkyl-, wherein the alkyl portion is optionally substituted with 1-3 fluoros, or
(l) hetAr 2 C(═O)—,
Ar 1 is phenyl optionally substituted with one or more substituents independently selected from the group consisting of halogen, CN, C1-C6 alkyl (optionally substituted with 1-3 fluoros), C1-C6 alkoxy (optionally substituted with 1-3 fluoros), R e R f N— wherein R e and R f are independently H or C1-C6 alkyl, (R p R q N)C1-C6 alkoxy- wherein R P and R q are independently H or C1-C6 alkyl, and (hetAr a )C1-C6 alkyl- wherein hetAr a is a 5-6 membered heteroaryl ring having 1-2 ring nitrogen atoms, or Ar 1 is a phenyl ring fused to a 5-6 membered heterocyclic ring having 1-2 ring heteroatoms independently selected from N and 0; and
hetAr 2 is a 5-6 membered heteroaryl ring having 1-3 ring heteroatoms independently selected from N, O and S or a 9-10 membered bicyclic heteroaryl ring having 1-3 ring nitrogen atoms, wherein hetAr 2 is optionally substituted with one or more substituents independently selected from the group consisting of halogen, CN, C1-C6 alkyl (optionally substituted with 1-3 fluoros), C1-C6 alkoxy (optionally substituted with 1-3 fluoros), (C1-C6 alkoxy)C1-C6 alkyl-(optionally substituted with 1-3 fluoros), R e R f N— wherein R e and R f are independently H or C1-C6 alkyl, OH, (C1-C6 alkoxy)C1-C6 alkoxy- and C3-C6 cycloalkyl.

2. A compound according to claim 1 , wherein Ring D is

wherein the wavy line indicates the point of attachment to the ring comprising X 1 , X 2 , X 3 and X 4 , and the asterisk indicates the point of attachment to the E group, and wherein said ring is optionally substituted with (a) one to four groups independently selected from halogen, OH, C1-C3 alkyl which is optionally substituted with 1-3 fluoros, or C1-C3 alkoxy which is optionally substituted with 1-3 fluoros, (b) a C3-C6 cycloalkylidene ring, or (c) an oxo group.

3. A compound according to claim 2 , wherein E is:
(h) Ar 1 C1-C6 alkyl-, or
(j) hetAr 2 C1-C6 alkyl- wherein said alkyl portion is optionally substituted with 1-3 fluoros.

4. A compound according to claim 1 , wherein Ring D is

wherein the wavy line indicates the point of attachment to the ring comprising X 1 , X 2 , X 3 and X 4 , and the asterisk indicates the point of attachment to the E group, and wherein said ring is optionally substituted with (a) one to four groups independently selected from halogen, OH, C1-C3 alkyl which is optionally substituted with 1-3 fluoros, or C1-C3 alkoxy which is optionally substituted with 1-3 fluoros, (b) a C3-C6 cycloalkylidene ring, or (c) an oxo group.

5. A compound according to claim 4 , wherein E is
(j) hetAr 2 C1-C6 alkyl- wherein said alkyl portion is optionally substituted with 1-3 fluoros, or
(l) hetAr 2 C(═O)—.

6. A compound according to claim 3 , wherein B is
(c) hydroxyC2-C6 alkyl- wherein the alkyl portion is optionally substituted with a C3-C6 cycloalkylidene ring,
(e) (C1-C6 alkoxy)C1-C6 alkyl- optionally substituted with 1-3 fluoros, or
(i) (hetCyc a )C1-C3 alkyl-.

7. A compound according to claim 5 , wherein B is
(b) C1-C6 alkyl optionally substituted with 1-3 fluoros, or
(c) hydroxyC2-C6 alkyl- wherein the alkyl portion is optionally substituted with a C3-C6 cycloalkylidene ring,
(f) (R 1 R 2 N)C1-C6 alkyl-, wherein said alkyl portion is optionally substituted with OH and wherein R 1 and R 2 are independently H or C1-C6 alkyl (optionally substituted with 1-3 fluoros);
(g) hetAr 1 C1-C3 alkyl-, wherein hetAr 1 is a 5-6 membered heteroaryl ring having 1-3 ring heteroatoms independently selected from N, O and S and is optionally substituted with one or more independently selected C1-C6 alkyl substituents; or
(i) (hetCyc a )C1-C3 alkyl-.

8. A compound according to claim 1 , wherein X 1 is N, and X 2 , X 3 and X 4 are CH.

9. A compound according to claim 1 , wherein the compound of Formula I is selected from the group consisting of:
4-(6-(4-benzylpiperazin-1-yl)pyridin-3-yl)-6-(2-morpholinoethoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile;
6-(2-hydroxyethoxy)-4-(6-(6-((6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile;
(R)-6-(2-hydroxypropoxy)-4-(6-(4-((6-methoxypyridin-3-yl)methyl)piperazin-1-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile;
6-(2-hydroxy-2-methylpropoxy)-4-(6-(6-((6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile;
6-(2-methoxyethoxy)-4-(6-(4-((6-methoxypyridin-3-yl)methyl)piperazin-1-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile;
6-(2-hydroxy-2-methylpropoxy)-4-(6-(6-(6-methoxynicotinoyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile;
6-(2-(dimethylamino)ethoxy)-4-(6-(6-((6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile;
4-(6-(6-((6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)-6-(2-morpholinoethoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile;
4-(6-(6-((6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyridin-3-yl)-6-((l-methyl-1H-imidazol-4-yl)methoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile; and
6-ethoxy-4-(5-(6-((5-fluoro-6-methoxypyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptan-3-yl)pyrazin-2-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile;

or a pharmaceutically acceptable salt thereof.

Assignees

• Array Biopharma Inc
• Array Biopharma Inc

Inventors

• Andrews Steven W
• Aronow Sean
• Blake James F
• Brandhuber Barbara J
• Cook Adam
• Haas Julia
• Jiang Yutong
• Kolakowski Gabrielle R
• Mcfaddin Elizabeth A
• Mckenney Megan L
• Mcnulty Oren T
• Metcalf Andrew T
• Moreno David A
• Tang Tony P
• Ren Li

Classifications

• A61K31/506

  not condensed and containing further heterocyclic rings · CPC title

• A61K31/5377

  not condensed and containing further heterocyclic rings, e.g. timolol · CPC title

• A61P35/02

  specific for leukemia · CPC title

• A61P1/12

  Antidiarrhoeals · CPC title

• A61K31/444

  containing a six-membered ring with nitrogen as a ring heteroatom, e.g. amrinone · CPC title