Enhancer of zeste homolog 2 inhibitors

A compound according to Formula (III)(a):

• wherein:
• R1 and R2 are each independently (C1-C4)alkoxy, (C1-C4)alkyl, or halo(C1-C4)alkyl;
• R3 is hydrogen;
• R4 is (C1-C3)alkyl or halogen;
• R5 is (C3-C8)cycloalkyl(C1-C2)alkyl- or heterocycloalkyl(C1-C2)alkyl-, each of which is optionally substituted 1, 2, or 3 times, independently, by halogen, —ORa, —NRaRb, —NHCO2Ra, nitro, (C1-C3)alkyl, RaRbN(C1-C3)alkyl-, RaO(C1-C3)alkyl-, (C3-C8)cycloalkyl, cyano, —CO2Ra, —C(O)NRaRb, —SO2NRaRb, heterocycloalkyl, aryl, or heteroaryl, wherein said (C3-C8)cycloalkyl, heterocycloalkyl, aryl, or heteroaryl is optionally substituted 1 or 2 times, independently, by halogen, (C1-C4)alkyl, halo(C1-C4)alkyl, —CO(C1-C4)alkyl, —CO2(C1-C4)alkyl, —NRaRb, —NHCO2Ra, hydroxyl, oxo, (C1-C4)alkoxy, or (C1-C4)alkoxy(C1-C4)alkyl-;
• R6 is selected from the group consisting of hydrogen, —SO2(C1-C4)alkyl, halogen, (C1-C6)alkyl, (C1-C4)alkoxy, phenyl, heteroaryl, and cyano, wherein said phenyl or heteroaryl group is optionally substituted 1 or 2 times, independently, by (C1-C4)alkoxy, —NRaRb, RaRbN(C1-C4)alkyl-, (C1-C4)alkylheterocycloalkyl-, halogen, (C1-C4)alkyl, (C3-C8)cycloalkyl, or heterocycloalkyl;
• and
• Ra and Rb are each independently hydrogen, (C1-C4)alkyl, (C1-C4)alkoxy(C1-C4)alkyl-, (C3-C10)cycloalkyl, heterocycloalkyl, aryl, aryl(C1-C4)alkyl-, heteroaryl(C1-C4)alkyl-, or heteroaryl, wherein any said cycloalkyl, heterocycloalkyl, aryl, or heteroaryl group is optionally substituted 1, 2, or 3 times, independently, by halogen, hydroxyl, (C1-C4)alkoxy, amino, —NH(C1-C4)alkyl, —N((C1-C4)alkyl)2, (C1-C4)alkyl, halo(C1-C4)alkyl, —CO2H, —CO2(C1-C4)alkyl, —CONH2, —CONH(C1-C4)alkyl, —CON((C1-C4)alkyl)2, —SO2(C1-C4)alkyl, —SO2NH2, —SO2NH(C1-C4)alkyl, or —SO2N((C1-C4)alkyl)2;
• or Ra and Rb taken together with the nitrogen to which they are attached represent a 5-8 membered saturated or unsaturated ring, optionally containing an additional heteroatom selected from oxygen, nitrogen, and sulfur, wherein said ring is optionally substituted 1, 2, or 3 times, independently, by (C1-C4)alkyl, halo(C1-C4)alkyl, amino, —NH(C1-C4)alkyl, —N((C1-C4)alkyl)2, hydroxyl, oxo, (C1-C4)alkoxy, or (C1-C4)alkoxy(C1-C4)alkyl-, wherein said ring is optionally fused to a (C3-C8)cycloalkyl, heterocycloalkyl, aryl, or heteroaryl ring;
• or Ra and Rb taken together with the nitrogen to which they are attached represent a 6- to 10-membered bridged bicyclic ring system optionally fused to a (C3-C8)cycloalkyl, heterocycloalkyl, aryl, or heteroaryl ring;
• or a pharmaceutically acceptable salt thereof.