A compound represented by formula or a pharmaceutically acceptable salt thereof: wherein: X is N, and Z is CH; R 1 is selected from the group consisting of Y, aryl substituted by Y, and alkyl substituted by Y; Y is -CO 2 H, -C NH 2, -C NH(C 1 -C 6)alkyl, -C N((C 1 -C 6)alkyl) 2, -C NH(aryl), C N(aryl)((C 1 -C 6)alkyl), C N(aryl) 2, -C NH((C 1 -C 6)haloalkyl), -S 2 NH 2,-S 2 NH((C 1 -C 6)alkyl), -S 2 NH((C 1 -C 6)haloalkyl), -S 2 NH(aryl), -S 2 NHC (C 1 -C 6)alkyl, -S 2 NHC (C 1 -C 6)haloalkyl, -S 2 NHC aryl, -N S 2 (C 1 -C 6)alkyl,-N S 2 aryl, -N S 2 (C 1 -C 6)haloalkyl, -NHC ((C 1 -C 6)alkyl), -NHC ((C 1 -C 6)haloalkyl), -NHC (aryl), -NHC NH(C 1 -C 6)alkyl, -NHC NHaryl, -C N S 2 (C 1 -C 6)alkyl, -C N S 2 aryl, C N S 2 ((C 1 -C 6)haloalkyl), or 1 H -tetrazolyl; R 2 and R 3 are each independently selected from the group consisting of H and aryl; R 4, R 5, R 6, and R 7 are each H; wherein R 8 is halo; m is 1; n is 0; further wherein any occurrence of (C 1 -C 6)alkyl, aryl(C 1 -C 6)alkyl, aryl, (C 3 -C 6)cycloalkyl, (C 1 -C 6)alkoxyl, (C 1 -C 6)haloalkyl, (C 1 -C 6)hydroxyalkyl, heteroaryl, or heteroaryl(C 1 -C 6)alkyl is optionally and independently substituted by one or more substituents selected from the group consisting of halo, (C 1 -C 6)alkyl, (C 1 -C 6)haloalkyl, aryl, -NH 2, -NH((C 1 -C 6)alkyl),-N((C 1 -C 6)alkyl) 2, -OH, (C 3 -C 6)cycloalkyl, (C 1 -C 6)alkoxyl, (C 1 -C 6)haloalkoxyl, -SH,-S((C 1 -C 6)alkyl), (C 1 -C 6)hydroxyalkyl, and (C 1 -C 6)alkoxy(C 1 -C 6)alkyl, -CN, -CF 3,-C NH 2, -C NH(R 12), -C N(R 12) 2, -N C (R 12), -N(R 12)C (R 12), -S 2 NH 2, -S 2 NH(R 12), -S 2 N(R 12) 2, -N S 2 (R 12), -N(R 12)S 2 (R 12), -NHC NH 2,-NHC NH(R 12), and -NHC N(R 12) 2; and each occurrence of R 12 is independently selected from the group consisting of (C 1 -C 6)alkyl), aryl, and aryl(C 1 -C 6)alkyl. X is N, and Z is CH; R 1 is selected from the group consisting of Y, aryl substituted by Y, and alkyl substituted by Y; Y is -CO 2 H, -C NH 2, -C NH(C 1 -C 6)alkyl, -C N((C 1 -C 6)alkyl) 2, -C NH(aryl), C N(aryl)((C 1 -C 6)alkyl), C N(aryl) 2, -C NH((C 1 -C 6)haloalkyl), -S 2 NH 2,-S 2 NH((C 1 -C 6)alkyl), -S 2 NH((C 1 -C 6)haloalkyl), -S 2 NH(aryl), -S 2 NHC (C 1 -C 6)alkyl, -S 2 NHC (C 1 -C 6)haloalkyl, -S 2 NHC aryl, -N S 2 (C 1 -C 6)alkyl,-N S 2 aryl, -N S 2 (C 1 -C 6)haloalkyl, -NHC ((C 1 -C 6)alkyl), -NHC ((C 1 -C 6)haloalkyl), -NHC (aryl), -NHC NH(C 1 -C 6)alkyl, -NHC NHaryl, -C N S 2 (C 1 -C 6)alkyl, -C N S 2 aryl, C N S 2 ((C 1 -C 6)haloalkyl), or 1 H -tetrazolyl; R 2 and R 3 are each independently selected from the group consisting of H and aryl; R 4, R 5, R 6, and R 7 are each H; wherein R 8 is halo; m is 1; n is 0; further wherein any occurrence of (C 1 -C 6)alkyl, aryl(C 1 -C 6)alkyl, aryl, (C 3 -C 6)cycloalkyl, (C 1 -C 6)alkoxyl, (C 1 -C 6)haloalkyl, (C 1 -C 6)hydroxyalkyl, heteroaryl, or heteroaryl(C 1 -C 6)alkyl is optionally and independently substituted by one or more substituents selected from the group consisting of halo, (C 1 -C 6)alkyl, (C 1 -C 6)haloalkyl, aryl, -NH 2, -NH((C 1 -C 6)alkyl),-N((C 1 -C 6)alkyl) 2, -OH, (C 3 -C 6)cycloalkyl, (C 1 -C 6)alkoxyl, (C 1 -C 6)haloalkoxyl, -SH,-S((C 1 -C 6)alkyl), (C 1 -C 6)hydroxyalkyl, and (C 1 -C 6)alkoxy(C 1 -C 6)alkyl, -CN, -CF 3,-C NH 2, -C NH(R 12), -C N(R 12) 2, -N C (R 12), -N(R 12)C (R 12), -S 2 NH 2, -S 2 NH(R 12), -S 2 N(R 12) 2, -N S 2 (R 12), -N(R 12)S 2 (R 12), -NHC NH 2,-NHC NH(R 12), and -NHC N(R 12) 2; and each occurrence of R 12 is independently selected from the group consisting of (C 1 -C 6)alkyl), aryl, and aryl(C 1 -C 6)alkyl.