IDO inhibitors

A compound of the formula,

• or a pharmaceutically acceptable salt thereof, wherein
• bond α is a single bond;
• n is 0, 1 or 2;
• each R1 is independently fluoro, chloro, hydroxy, or methoxy;
• R2 is —CH2—RA—, wherein
• RA is —CN, —C(O)R3, —C(O)OR3, —C(O)N(R3)(RC),
• —C(ORB)(R3)(RC), —C(NHRB)(R3)(RC), or —C(═N—ORC)R3, wherein
• RB is hydrogen or C1-6alkyl;
• R3 is
• wherein
• bond a is a single bond or a double bond;
• m is 0, 1, or 2;
• p is 0 or 1;
• and wherein
• when bond a is a single bond, then Z is —C(R36)2—, —C(═R32)—, —N(R35)—, or —O—, wherein
• R35 is hydrogen, C1-6alkyl, —C(O)R, —S(O)2R, —C(O)OR, —C(O)N(R)2, —S(O)2OR, or —S(O)2N(R)2;
• and when bond a is a double bond, then Z is —C(R36)═ or —N═;
• each R36 is independently hydrogen or R31;
• R32 is ═O, ═S, ═N(R), ═N(OR), ═C(R34)2, =(spiro-C3-8cycloalkyl), or =(spiro-(3-10 membered heterocyclyl)), wherein
• each R34 is independently hydrogen, halogen, C1-6alkyl, C1-6haloalkyl, C3-8cycloalkyl, or 3-10 membered heterocyclyl;
• or both R34 taken together with the atom to which they are both attached form a monocyclic C3-8cycloalkyl or monocyclic 3-8 membered heterocyclyl;
• each R31 is independently halogen, cyano, nitro, C1-6alkyl, —C1-6alkyl-R33, C1-6haloalkyl, —OR, —N(R)2, —SR, —C(O)OR, —C(O)N(R)2, —C(O)R, —S(O)R, —S(O)OR, —S(O)N(R)2, —S(O)2R, —S(O)2OR, —S(O)2N(R)2, —OC(O)R, —OC(O)OR, —OC(O)N(R)2, —N(R)C(O)R, —N(R)C(O)OR, —N(R)C(O)N(R)2, wherein
• R33 is cyano, —OR, —N(R)2, —SR, —C(O)OR, —C(O)N(R)2, —C(O)R, —S(O)R, —S(O)OR, —S(O)N(R)2, —S(O)2R, —S(O)2OR, —S(O)2N(R)2, —OC(O)R, —OC(O)OR, —OC(O)N(R)2, —N(R)C(O)R, —N(R)C(O)OR, or —N(R)C(O)N(R)2;
• RC is hydrogen or C1-6alkyl;
• and
• each R is independently hydrogen or R10, wherein
• R10 is C1-6alkyl, C1-6haloalkyl, aryl, heteroaryl, C3-8cycloalkyl, C3-8cycloalkenyl, 3-10 membered heterocyclyl, arylC1-6alkyl, heteroarylC1-6alkyl-, C3-8 cycloalkylC1-6alkyl-, C3-8cycloalkenylC1-6alkyl-, or (3-10 membered heterocyclyl)C1-6alkyl-, each R10 optionally substituted by one, two, three, or four groups that are each independently halogen, cyano, nitro, C1-6alkyl, C1-6haloalkyl, —OR11, —N(R11)2, —SR11, —C(O)OR11, —C(O)N(R11)2, —C(O)R11, —S(O)R11, —S(O)OR11, —S(O)N(R11)2, —S(O)2R11, —S(O)2OR11, —S(O)2N(R11)2, —OC(O)R11, —OC(O)OR11, —OC(O)N(R11)2, —N(R11)C(O)R11, —N(R11)C(O)OR11, —N(R11)C(O)N(R11)2, wherein each R11 is independently hydrogen or C1-6alkyl.