A compound, wherein the compound is either a compound of formula: or a pharmaceutically acceptable salt thereof, wherein: R 3 is halogen; X is N or CH; Y is C or N; and Z is C or N, wherein Y and Z are not both N, and when both Z and Y are C, the bond " " is a double bond, and R 1 and R 2 are taken together with the atoms to which they are bound to form a 3- to 10-membered aromatic or non-aromatic monocyclic ring having 0-3 heteroatoms or heteroatom groups independently selected from N, NH, O, S, SO, and SO 2, wherein said ring is substituted with 0-3 R, and wherein said ring is optionally fused to a C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or a 3- to 10- membered heterocyclyl, wherein said C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or 3- to 10- membered heterocyclyl is substituted with 0-3 R, wherein each occurrence of R is independently selected from methyl, ethyl, propyl, isopropyl, CH 2 CF 3, CF 3, cyclopropyl, F, Cl, Br, OH, methoxy and CN; or when one of Z and Y is N, the other is C, the bond " " is a single bond, and R 1 and R 2 are taken together with the atoms to which they are bound to form a 3- to 10-membered aromatic or non-aromatic monocyclic ring having 0-3 heteroatoms or heteroatom groups independently selected from N, NH, O, S, SO, and SO 2, wherein said ring is substituted with 0-3 R, and wherein said ring is optionally fused to a C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or a 3- to 10- membered heterocyclyl, wherein said C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or a 3- to 10- membered heterocyclyl is substituted with 0-3 R, wherein each occurrence of R is independently selected from methyl, ethyl, propyl, isopropyl, CH 2 CF 3, CF 3, cyclopropyl, F, Cl, Br, OH, methoxy and CN. R 3 is halogen; X is N or CH; Y is C or N; and Z is C or N, wherein Y and Z are not both N, and when both Z and Y are C, the bond " " is a double bond, and R 1 and R 2 are taken together with the atoms to which they are bound to form a 3- to 10-membered aromatic or non-aromatic monocyclic ring having 0-3 heteroatoms or heteroatom groups independently selected from N, NH, O, S, SO, and SO 2, wherein said ring is substituted with 0-3 R, and wherein said ring is optionally fused to a C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or a 3- to 10- membered heterocyclyl, wherein said C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or 3- to 10- membered heterocyclyl is substituted with 0-3 R, wherein each occurrence of R is independently selected from methyl, ethyl, propyl, isopropyl, CH 2 CF 3, CF 3, cyclopropyl, F, Cl, Br, OH, methoxy and CN; or when both Z and Y are C, the bond " " is a double bond, and R 1 and R 2 are taken together with the atoms to which they are bound to form a 3- to 10-membered aromatic or non-aromatic monocyclic ring having 0-3 heteroatoms or heteroatom groups independently selected from N, NH, O, S, SO, and SO 2, wherein said ring is substituted with 0-3 R, and wherein said ring is optionally fused to a C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or a 3- to 10- membered heterocyclyl, wherein said C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or 3- to 10- membered heterocyclyl is substituted with 0-3 R, wherein each occurrence of R is independently selected from methyl, ethyl, propyl, isopropyl, CH 2 CF 3, CF 3, cyclopropyl, F, Cl, Br, OH, methoxy and CN; or when one of Z and Y is N, the other is C, the bond " " is a single bond, and R 1 and R 2 are taken together with the atoms to which they are bound to form a 3- to 10-membered aromatic or non-aromatic monocyclic ring having 0-3 heteroatoms or heteroatom groups independently selected from N, NH, O, S, SO, and SO 2, wherein said ring is substituted with 0-3 R, and wherein said ring is optionally fused to a C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or a 3- to 10- membered heterocyclyl, wherein said C 6-10 aryl, 5- to 10- membered heteroaryl, C 3-10 cycloalkyl, or a 3- to 10- membered heterocyclyl is substituted with 0-3 R, wherein each occurrence of R is independently selected from methyl, ethyl, propyl, isopropyl, CH 2 CF 3, CF 3, cyclopropyl, F, Cl, Br, OH, methoxy and CN.