A compound according to formula: or a pharmaceutically acceptable salt thereof, wherein R 1 is pyridyl optionally substituted at a substitutable position with one or more of R 8; wherein R 8 is halogen, -CN, -OH, -SH, -NO 2, -NH 2, -NH(C 1 -C 6 alkyl), -N(C 1 -C 6 alkyl) 2, -NH(C 1 -C 6 alkyl)-OH, -NH(C 1 -C 6 alkyl)-(C 1 -C 6 alkoxy), -C 1 -C 6 alkoxy-OH, -C 1 -C 6 alkoxy-(C 1 -C 6 alkoxy),C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkyl, C 1 -C 6 haloalkoxy, hydroxy(C 1 -C 6 alkyl), (C 1 -C 6 alkoxy)C 1 -C 6 alkyl, amino(C 1 -C 6 alkyl), -S(C 1 -C 6 alkyl), -CO 2 H, -CO 2 (C 1 -C 6 alkyl), -C (C 1 -C 6 alkyl), -SO 2 (C 1 -C 6 alkyl), -SO 2 NH 2, -SO 2 NH(C 1 -C 6 alkyl), -SO 2 N(C 1 -C 6 alkyl), -CON OR 80 where R 80 is hydrogen or a hydroxy protecting group, -CONH 2, -CONH(C 1 -C 6 alkyl), -CON(C 1 -C 6 alkyl) 2, -NHCO(C 1 -C 6 alkyl), -C(=NH)NH 2, -C(=NH)NH-NH 2, -C(=NOH)NH 2, or -NHCO 2 (C 1 -C 6 alkyl) wherein each alkyl, alkenyl, alkynyl, alkoxy is optionally substituted at a substitutable carbon with - CO 2 (C 1 -C 6)alkyl or -CON OR 80; R 7 is hydrogen or C 1 -C 8 alkyl optionally substituted with C 1 -C 4 alkoxycarbonyl; R 2 is hydrogen, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 1 -C 6 haloalkyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkoxy, C 3 -C 8 cycloalkyl, aryl, heteroaryl, heterocyclyl, (C 3 -C 8 cycloalkyl)C 1 -C 6 alkyl, (aryl)C 1 -C 6 alkyl, (heteroaryl)C 1 -C 6 alkyl, (heterocyclyl)C 1 -C 6 alkyl, (aryloxy)C 1 -C 6 alkyl, or (heteroaryloxy)C 1 -C 6 alkyl, wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, or heterocyclyl group is optionally substituted at a substitutable position with one or more of R 10; wherein R 10 is halogen, -CN, -OH, -NO 2, -NH 2, -NH(C 1 -C 6 alkyl), -N(C 1 -C 6 alkyl) 2, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkoxy, hydroxy(C 1 -C 6 alkyl), (C 1 -C 6 alkoxy)C 1 -C 6 alkyl, amino(C 1 -C 6 alkyl), -CO 2 H, -CO 2 (C 1 -C 6 alkyl), -SO 2 (C 1 -C 6 alkyl), -CONH 2, -CONH(C 1 -C 6 alkyl), -CON(C 1 -C 6 alkyl) 2, -CON OR 80, -NHCO(C 1 -C 6 alkyl), or -NHCO 2 (C 1 -C 6 alkyl), wherein each alkyl, alkenyl, alkynyl, alkoxy is optionally substituted at a substitutable carbon with one R 102, where R 102 is -COR 104 where R 104 is -(C 1 -C 6)alkoxy, -NHOR 80, or - NR 7 R 110, where R 110 is aryl or heteroaryl, each of which is optionally substituted with up to three of halogen, -CN, -OH, -SH, -NO 2, -NH 2, -NH(C 1 -C 6 alkyl), -N(C 1 -C 6 alkyl) 2, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkyl, C 1 -C 6 haloalkoxy, hydroxy(C 1 -C 6 alkyl), (C 1 -C 6 alkoxy)C 1 -C 6 alkyl, amino(C 1 -C 6 alkyl), or -S(C 1 -C 6 alkyl); R 3 is hydrogen, halogen, -CN, -OH, -SH, -NO 2, -NH 2, -NH(C 1 -C 6 alkyl), -N(C 1 -C 6 alkyl) 2, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 1 -C 6 haloalkyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkoxy, C 3 -C 8 cycloalkyl, aryl, heteroaryl, heterocyclyl, (aryl)C 1 -C 6 alkyl, or (heteroaryl)C 1 -C 6 alkyl; A is -N(R 7)C -, -N(R 7)C O-, -C N(R 7)-, -N(R 7)C N(R 7)-, -OC N(R 7)-, -S 2 N(R 7)-, -OS 2 N(R,)-, -N(R 7)S 2 -, or -OS 2 O-; each R 5 is independently hydrogen, halogen, -CN, -OH, -SH, -NO 2, -NH 2, -NH(C 1 -C 6 alkyl), -N(C 1 -C 6 alkyl) 2, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 1 -C 6 haloalkyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkoxy, hydroxy(C 1 -C 6 alkyl), (C 1 -C 6 alkoxy)C 1 -C 6 alkyl, amino(C 1 -C 6 alkyl), C 3 -C 8 cycloalkyl, aryl, heteroaryl, heterocyclyl, (aryl)C 1 -C 6 alkyl, or (heteroaryl)C 1 -C 6 alkyl wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, or heterocyclyl group is optionally substituted at a substitutable position with one or more of R 10; each Z is independently N or CR 6, provided only one Z is N; and each R 6 is independently hydrogen, halogen, -CN, -OH, -SH, -NO 2, -NH 2, -NH(C 1 -C 6 alkyl), -N(C 1 -C 6 alkyl) 2, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 1 -C 6 haloalkyl, C 1 -C 6 alkoxy, C 1 -C 6 haloalkoxy, hydroxy(C 1 -C 6 alkyl), (C 1 -C 6 alkoxy)C 1 -C 6 alkyl, amino(C 1 -C 6 alkyl), C 3 -C 8 cycloalkyl, aryl, heteroaryl, heterocyclyl, (aryl)C 1 -C 6 alkyl, or (heteroaryl)C 1 -C 6 alkyl wherein each alkyl, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, or heterocyclyl group is optionally substituted at a substitutable position with one or more of R 10.