5 or 8-substituted imidazo[1,5-a]pyridines as indoleamine and/or tryptophane 2,3-dioxygenases

A compound having the structure of Formula (IB):

• or a stereoisomer thereof, or a pharmaceutically acceptable salt thereof,
• wherein:
• n is 0, 1, 2, 3, or 4;
• Ra and Rb are each independently hydrogen, halogen, C1-8 alkyl, C1-8 haloalkyl, C2-8 alkenyl, C2-8 alkynyl, C3-8 cycloalkyl, heterocyclyl, aryl, or heteroaryl;
• R1 is hydrogen, halogen, C1-8 alkyl or C1-8 haloalkyl;
• R2 and R3 are each independently hydrogen, halogen, OR7, NR7R8, COR7, SO2R7, C(═O)OR7, C(═O)NR7R8, C1-8 alkyl, C2-8 alkenyl, C2-8 alkynyl, C3-8 cycloalkyl, heterocyclyl, aryl, or heteroaryl, wherein said C1-8 alkyl, C2-8 alkenyl, C2-8 alkynyl, C3-8 cycloalkyl, heterocyclyl, aryl, and heteroaryl are each independently optionally substituted with at least one substituent R9;
• R4, R5 and R6 are each independently hydrogen, halogen, C1-8 alkyl, C2-8 alkenyl, C2-8 alkynyl, C3-8 cycloalkyl, C1-8 haloalkyl, aryl, heterocyclyl, heteroaryl, —CN, —OR7, or —SR7, wherein said C1-8 alkyl, C2-8 alkenyl, C2-8 alkynyl, C3-8 cycloalkyl, C1-8 haloalkyl, aryl, heterocyclyl, and heteroaryl are each independently optionally substituted with at least one substituted R9,
• provided that at least one of R4 and R5 is not hydrogen;
• RC is C3-10 cycloalkyl, heterocyclyl or heteroaryl, each optionally substituted with at least one substituent R9;
• R7 and R8 are each independently hydrogen, C1-8 alkyl, C1-8 haloalkyl, C3-8 cycloalkyl, heterocyclyl, aryl, or heteroaryl optionally substituted with at least one substituent R9;
• or R7 and R8 together with the nitrogen atom to which they are attached form a heterocyclyl or heteroaryl ring which optionally comprises a further hetero atom selected from nitrogen, oxygen or sulfur atom, and is optionally substituted with at least one substituent R9;
• R9 is hydrogen, halogen, C1-4 haloalkyl, C1-4 alkyl, C2-8 alkenyl, C3-6 cycloalkyl, aryl, heteroaryl, heterocyclyl, alkynyl, oxo, —C1-4 alkyl-NR′R″, —CN, —OR′, —NR′R″, —COR′, —CO2R′, —CONR′R″, —C(═NR′)NR″R′″, nitro, —NR′COR″, —NR′CONR′R″, —NR′CO2R″, —SO2R′, —SO2aryl, —NR′SO2NR″R′″, NR′SO2R″, or —NR′SO2aryl, wherein said C1-4 alkyl, C1-4 haloalkyl, C3-6 cycloalkyl, aryl, heteroaryl, and heterocyclyl group are each independently optionally substituted by one, two or three substituents selected from halo, hydroxyl, C1-4 alkyl and C1-4 haloalkyl;
• and
• R′, R″, and R′″ are each independently H, C1-4 haloalkyl, C1-4 alkyl, C2-4 alkenyl, C2-4 alkynyl, C3-6 cycloalkyl, heterocyclyl, aryl, or heteroaryl, each of which is optionally substituted by one or more halogen, C1-4 haloalkyl or C1-4 alkyl, or (R′ and R″), and/or (R″ and R′″) together with the atoms to which they are attached, form a ring selected from heterocyclyl optionally substituted by halogen, C1-4 haloalkyl or C1-4 alkyl and heteroaryl rings optionally substituted by halogen, C1-4 haloalkyl or C1-4 alkyl.