Dihydropyrido[2,3-d]pyrimidinone compounds as CDK2 inhibitors

1. A compound of Formula (I):

or a pharmaceutically acceptable salt thereof, wherein:

R 1 is selected from H, C 1-6 alkyl, and C 1-6 haloalkyl;

R 2 is selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, 5-10 membered heteroaryl-C 1-4 alkyl, C(═O)R b , C(═O)NR c R d , C(═O)OR a , C(═NR e )R b , C(═NR e )NR c R d , S(═O)R b , S(═O)NR c R d , NR c S(═O) 2 R b , NR c S(═O) 2 NR c R d , S(═O) 2 R b , and S(═O) 2 NR c R d , wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R 2A substituents;

each R a , R c , and R d is independently selected from H, C 1-6 alkyl, C 1-6 haloalkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R 2A substituents;

each R b is independently selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl, each of which are optionally substituted with 1, 2, 3, or 4 independently selected R 2A substituents;

each R e is independently selected from H, CN, OH, C 1-4 alkyl, and C 1-4 alkoxy;

each R f is independently selected from H, C 1-4 alkyl, and C 1-4 haloalkyl;

R 3 is selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R 3A substituents;

R 4 , R 5 , R 6 , and R 7 have the definitions in Group (a) or (b):

Group (a):

R 4 and R 5 are independently selected from halo, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

or, alternatively, R 4 and R 5 , together with the carbon atom to which they are attached, form a 3, 4, 5, 6, or 7 membered cycloalkyl ring or a 3, 4, 5, 6, or 7 membered heterocycloalkyl ring, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

R 6 and R 7 are independently selected from H, D, halo, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

or, alternatively, R 6 and R 7 , together with the carbon atom to which they are attached, form a 3, 4, 5, 6, or 7 membered cycloalkyl ring or a 3, 4, 5, 6, or 7 membered heterocycloalkyl ring, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

Group (b):

R 4 and R 5 are independently selected from H, halo, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

or, alternatively, R 4 and R 5 , together with the carbon atom to which they are attached, form a 3, 4, 5, 6, or 7 membered cycloalkyl ring or a 3, 4, 5, 6, or 7 membered heterocycloalkyl ring, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

R 6 and R 7 are independently selected from halo, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, and C 3-6 cycloalkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

or, alternatively, R 6 and R 7 , together with the carbon atom to which they are attached, form a 3, 4, 5, 6, or 7 membered cycloalkyl ring or a 3, 4, 5, 6, or 7 membered heterocycloalkyl ring, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

each R 2A is independently selected from H, D, halo, CN, NO 2 , C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, 5-10 membered heteroaryl-C 1-4 alkyl, OR a1 , SR a1 , C(═O)R b1 , C(═O)NR c1 R d1 , C(═O)OR a1 , OC(═O)R b1 , OC(═O)NR c1 R d1 , NR c1 R d1 , NR c1 C(═O)R b1 , NR c1 C(═O)OR b1 , NR c1 C(═O)NR c1 R d1 , C(═NR e )R b1 , C(═NR e )NR c1 R d1 , NR c1 C(═NR e ) NR c1 R d1 , NHOR a1 , NR c1 S(═O)R b1 , NR c1 S(═O)NR c1 R d1 , S(═O)R b1 , S(═O)NR c1 R d1 , NR c1 S(═O) 2 R b1 , NR c1 S(═O) 2 NR c1 R d1 , S(═O) 2 R b1 , S(═O)(═NR f )R b1 , and S(═O) 2 NR c1 R d1 , wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R 2B substituents;

each R a1 , R c1 , and R d1 is independently selected from H, C 1-6 alkyl, C 1-6 haloalkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R 2B substituents;

each R b1 is independently selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl, each of which are optionally substituted with 1, 2, 3, or 4 independently selected R 2B substituents;

each R 3A is independently selected from H, D, halo, CN, NO 2 , C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, 5-10 membered heteroaryl-C 1-4 alkyl, OR a2 , SR a2 , C(═O)R b2 , C(═O)NR c2 R d2 , C(═O)OR a2 , OC(═O)R b2 , OC(═O)NR c2 R d2 ,NR c2 R d2 , NR c2 C(═O)R b2 , NR c2 C(═O)OR b2 , NR c2 C(═O)NR c2 R d2 , C(═NR e )R b2 , C(═NR e )NR c2 R d2 , NR c2 C(═NR e )NR c2 R d2 , NHOR a2 , NR c2 S(═O)R b2 , NR c2 S(═O)NR c2 R d2 , S(═O)R b2 , S(═O)NR c2 R d2 , NR c2 S(═O) 2 R b2 , NR c2 S(═O) 2 NR c2 R d2 , S(═O) 2 R b2 , S(═O)(═NR f )R b2 , and S(═O) 2 NR c2 R d2 , wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R 3B substituents;

each R a2 , R c2 , and R d2 is independently selected from H, C 1-6 alkyl, C 1-6 haloalkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R 3B substituents;

each R b2 is independently selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-10 cycloalkyl, C 6-10 aryl, 4-10 membered heterocycloalkyl, 5-10 membered heteroaryl, C 3-10 cycloalkyl-C 1-4 alkyl, C 6-10 aryl-C 1-4 alkyl, 4-10 membered heterocycloalkyl-C 1-4 alkyl, and 5-10 membered heteroaryl-C 1-4 alkyl, each of which are optionally substituted with 1, 2, 3, or 4 independently selected R 3B substituents;

each R 2B and R 3B is independently selected from H, D, halo, CN, NO 2 , C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, 5-6 membered heteroaryl-C 1-4 alkyl, OR a23 , SR a23 , C(═O)R b23 , C(═O)NR c23 R d23 , C(═O)OR a23 , OC(═O)R b23 , OC(═O)NR c23 R d23 , NR c23 R d23 , NR c23 C(═O)R b23 , NR c23 C(═O)OR b23 , NR c23 C(═O)NR c23 R d23 , C(═NR e )R b23 , C(═NR e )NR c23 R d23 , NR c23 C(═NR e )NR c23 R d23 , NHOR a23 , NR c23 S(═O)R b23 , NR c23 S(═O)NR c23 R d23 , S(═O)R b23 , S(═O)NR c23 R d23 , NR c23 S(═O) 2 R b23 , NR c23 S(═O) 2 NR c23 R d23 , S(═O) 2 R b23 , S(═O)(═NR f )R b23 , and S(═O) 2 NR c23 R d23 , wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

each R a23 , R c23 , and R d23 is independently selected from H, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, wherein said C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl are each optionally substituted with 1, 2, 3, or 4 independently selected R G substituents;

each R b23 is independently selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, each of which are optionally substituted with 1, 2, 3, or 4 independently selected R G substituents; and

each R G is independently selected from OH, NO 2 , CN, halo, C 1-3 alkyl, C 2-3 alkenyl, C 2-3 alkynyl, C 1-3 haloalkyl, cyano-C 1-3 alkyl, HO—C 1-3 alkyl, C 1-3 alkoxy-C 1-3 alkyl, C 1-3 alkoxy, C 1-3 haloalkoxy, amino, C 1-3 alkylamino, di(C 1-3 alkyl)amino, thio, C 1-3 alkylthio, C 1-3 alkylsulfinyl, C 1-3 alkylsulfonyl, carbamyl, C 1-3 alkylcarbamyl, di(C 1-3 alkyl)carbamyl, carboxy, C 1-3 alkylcarbonyl, C 1-3 alkoxycarbonyl, C 1-3 alkylcarbonyloxy, C 1-3 alkylcarbonylamino, C 1-3 alkoxycarbonylamino, C 1-3 alkylaminocarbonyloxy, C 1-3 alkylsulfonylamino, aminosulfonyl, C 1-3 alkylaminosulfonyl, di(C 1-3 alkyl)aminosulfonyl, aminosulfonylamino, C 1-3 alkylaminosulfonylamino, di(C 1-3 alkyl)aminosulfonylamino, aminocarbonylamino, C 1-3 alkylaminocarbonylamino, and di(C 1-3 alkyl)aminocarbonylamino;

wherein “heterocycloalkyl” refers to monocyclic heterocycles or polycyclic heterocycles having 2, 3, or 4 fused, spirocyclic, or bridged rings, wherein at least one of the rings of the polycyclic heterocycle is a non-aromatic ring (saturated or partially unsaturated ring), wherein 1, 2, 3, or 4 of the ring-forming carbon atoms of the monocyclic heterocycle or polycyclic heterocycle is replaced by a heteroatom independently selected from N, O, S, and B; wherein the heterocycloalkyl group can contain one or more aromatic rings fused to (having a bond in common with) the non-aromatic heterocyclic ring; wherein the ring-forming carbon atoms and heteroatoms of the heterocycloalkyl group can be optionally substituted by one or more oxo or sulfido (C(O), S(O), C(S), or S(O) 2 ); and wherein the heterocycloalkyl group can have one or more oxidized ring members; and

wherein “heteroaryl” refers to monocyclic aromatic heterocycles or polycyclic aromatic heterocycles having 2, 3, or 4 fused rings, wherein the monocyclic aromatic heterocycle or polycyclic aromatic heterocycle has 1, 2, 3, or 4 heteroatom ring members independently selected from N, O, S and B, and wherein any ring-forming N in a heteroaryl moiety can be an N-oxide.

2. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 1 is H.

3. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 2 is selected from C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R 2A substituents.

4. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 2 is selected from 4-7 membered heterocycloalkyl and phenyl, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R 2A substituents.

5. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 2 is selected from piperidin-4-yl and phenyl, each of which is substituted with 1 R 2A substituent.

6. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein each R 2A is independently selected from halo, CN, NO 2 , C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, OR a1 , SR a1 , C(═O)R b1 , C(═O)NR c1 R d1 , C(═O)OR a1 , OC(═O)R b1 , OC(═O)NR c1 R d1 , NR c1 R d1 , NR c1 C(═O)R b1 , NR c1 C(═O)OR b1 , NR c1 C(═O)NR c1 R d1 , NHOR a1 , NR c1 S(═O) 2 R b1 , NR c1 S(═O) 2 NR c1 R d1 , S(═O) 2 R b1 , and S(═O) 2 NR c1 R d1 ;

each R a1 , R c1 , and R d1 is independently selected from H, C 1-6 alkyl, and C 1-6 haloalkyl; and

each R b1 is independently selected from C 1-6 alkyl and C 1-6 haloalkyl.

7. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein at least one R 2A is selected from S(═O) 2 R b1 and S(═O) 2 NR c1 R d1 , wherein R b1 is C 1-3 alkyl; and R c1 and R d1 are each independently selected from H and C 1-3 alkyl.

8. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein each R 2A is independently selected from S(═O) 2 CH 3 and S(═O) 2 NH 2 .

9. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 3 is selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R 3A substituents.

10. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 3 is selected from C 1-6 alkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, each of which is optionally substituted with 1 or 2 independently selected R 3A substituents.

11. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 3 optionally substituted with 1, 2, 3, or 4 independently selected R 3A substituents is selected from 1,1-difluorobutan-2-yl, cyclopentyl, phenyl, tetrahydrofuran-3-yl, and (1-methyl-1H-pyrazol-5-yl)methyl.

12. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein each R 3A is independently selected from halo, CN, NO 2 , C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, OR a2 , SR a2 , C(═O)R b2 , C(═O)NR c2 R d2 , C(═O)OR a2 , OC(═O)R b2 OC(═O)NR c2 R d2 , NR c2 R d2 , NR c2 C(═O)R b2 , NR c2 C(═O)OR b2 , NR c2 C(═O)NR c2 R d2 , NHOR a2 , NR c2 S(═O) 2 R b2 , NR c2 S(═O) 2 NR c2 R d2 , S(═O) 2 R b2 , and S(═O) 2 NR c2 R d2 ;

each R a2 , R c2 , and R d2 is independently selected from H, C 1-6 alkyl, and C 1-6 haloalkyl; and

each R b2 is independently selected from C 1-6 alkyl and C 1-6 haloalkyl.

13. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein each R 3A is independently selected from H, halo, C 1-6 alkyl, and C 1-6 haloalkyl.

14. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 4 and R 5 are each independently selected from C 1-6 alkyl and C 1-6 haloalkyl; or, alternatively, R 4 and R 5 , together with the carbon atom to which they are attached form a 3, 4, 5, or 6 membered cycloalkyl ring.

15. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 4 and R 5 are each independently C 1-6 alkyl.

16. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 4 and R 5 are each methyl.

17. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 4 and R 5 are each methyl; or R 4 and R 5 , together with the carbon atom to which they are attached, form a cyclopropyl ring.

18. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 6 and R 7 are each independently selected from H, C 1-6 alkyl and C 1-6 haloalkyl.

19. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein R 6 and R 7 are each H.

20. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein:

R 1 is H;

R 2 is selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R 2A substituents;

R 3 is selected from C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, 5-6 membered heteroaryl, C 3-7 cycloalkyl-C 1-4 alkyl, phenyl-C 1-4 alkyl, 4-7 membered heterocycloalkyl-C 1-4 alkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R 3A substituents;

R 4 and R 5 are each independently selected from C 1-6 alkyl and C 1-6 haloalkyl;

or, alternatively, R 4 and R 5 , together with the carbon atom to which they are attached form a 3, 4, 5, or 6 membered cycloalkyl ring;

R 6 and R 7 are each independently selected from H and C 1-6 alkyl;

each R 2A is independently selected from halo, CN, NO 2 , C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, OR a1 , SR a1 , C(═O)R b1 , C(═O)NR c1 R d1 , C(═O)OR a1 , OC(═O)R b1 , OC(═O)NR c1 R d1 , NR c1 R d1 , NR c1 C(═O)R b1 , NR c1 C(═O)OR b1 , NR c1 C(═O)NR c1 R d1 , NHOR a1 , NR c1 S(═O) 2 R b1 , NR c1 S(═O) 2 NR c1 R d1 , S(═O) 2 R b1 , and S(═O) 2 NR c1 R d1 ;

each R a1 , R c1 , and R d1 is independently selected from H, C 1-6 alkyl, and C 1-6 haloalkyl;

each R b1 is independently selected from C 1-6 alkyl and C 1-6 haloalkyl;

each R 3A is independently selected from halo, CN, NO 2 , C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 1-6 haloalkyl, OR a2 , SR a2 , C(═O)R b2 , C(═O)NR c2 R d2 , C(═O)OR a2 , OC(═O)R b2 OC(═O)NR c2 R d2 , NR c2 R d2 , NR c2 C(═O)R b2 , NR c2 C(═O)OR b2 , NR c2 C(═O)NR c2 R d2 , NHOR a2 , NR c2 S(═O) 2 R b2 , NR c2 S(═O) 2 NR c2 R d2 , S(═O) 2 R b2 , and S(═O) 2 NR c2 R d2 ;

each R a2 , R c2 , and R d2 is independently selected from H, C 1-6 alkyl, and C 1-6 haloalkyl; and

each R b2 is independently selected from C 1-6 alkyl and C 1-6 haloalkyl.

21. The compound of claim 1 , or a pharmaceutically acceptable salt thereof, wherein:

R 1 is H;

R 2 is selected from 4-7 membered heterocycloalkyl and phenyl, each of which are substituted by 1 R 2A group;

R 2A is S(═O) 2 R b1 or S(═O) 2 NR c1 R d1 ;

R b1 is C 1-3 alkyl;

R c1 and R d1 are each independently selected from H and C 1-3 alkyl;

R 3 is selected from C 1-6 alkyl, C 3-7 cycloalkyl, phenyl, 4-7 membered heterocycloalkyl, and 5-6 membered heteroaryl-C 1-4 alkyl, each of which is optionally substituted with 1, 2, 3, or 4 independently selected R 3A substituents;

each R 3A is independently selected from H, halo, C 1-6 alkyl, and C 1-6 haloalkyl;

R 4 and R 5 are each methyl;

or R 4 and R 5 , together with the carbon atom to which they are attached form, form a cyclopropyl ring; and

R 6 and R 7 are each H.

22. The compound of claim 1 , selected from:

4-((8-cyclopentyl-6,6-dimethyl-7-oxo-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidin-2-yl)amino)benzenesulfonamide;

8-cyclopentyl-6,6-dimethyl-2-((1-(methylsulfonyl)piperidin-4-yl)amino)-5,8-dihydropyrido[2,3-d]pyrimidin-7(6H)-one; and

6,6-dimethyl-2-((1-(methylsulfonyl)piperidin-4-yl)amino)-8-phenyl-5,8-dihydropyrido[2,3-d]pyrimidin-7(6H)-one;

or a pharmaceutically acceptable salt thereof.

23. The compound of claim 1 , selected from:

8-(1,1-difluorobutan-2-yl)-6,6-dimethyl-2-((1-(methylsulfonyl)piperidin-4-yl)amino)-5,8-dihydropyrido[2,3-d]pyrimidin-7(6H)-one;

6,6-dimethyl-8-((1-methyl-1H-pyrazol-5-yl)methyl)-2-((1-(methylsulfonyl)piperidin-4-yl)amino)-5,8-dihydropyrido[2,3-d]pyrimidin-7(6H)-one; and

6,6-dimethyl-2-((1-(methylsulfonyl)piperidin-4-yl)amino)-8-(tetrahydrofuran-3-yl)-5,8-dihydropyrido[2,3-d]pyrimidin-7(6H)-one;

or a pharmaceutically acceptable salt thereof.

24. A pharmaceutical composition comprising a compound of claim 1 , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.