A compound of formula I-a or I-b, or a pharmaceutically acceptable salt thereof, wherein: Ring B is R 1 is -CH 3, -CF 3, -CN, -OCH 3, or -OCF 3; each R 2 is independently -H, -R, halogen, -haloalkyl, -OR, -SR, -CN, -NO 2, -SO 2 R, -SOR, -C R, -CO 2 R, -C N 2, -NRC R, -NRC N 2, -NRSO 2 R, or -N 2; each R 3 is independently -H, -R, halogen, -haloalkyl, -OR, -SR, -CN, -NO 2, -SO 2 R, -SOR, -C R, -CO 2 R, -C N 2, -NRC R, -NRC N 2, -NRSO 2 R, or -N 2; X is -CH 2 -; Y is C(R 4) 2 or NR 4; each R 4 is independently -H, -R, halogen, -haloalkyl, -OR, -SR, -CN, -NO 2, -SO 2 R, -SOR, -C R, -CO 2 R, -C N 2, -C R, -C NR 2, -NRC R, -NRC N 2, - NRSO 2 R, or -N 2; R 5 is independently methyl, ethyl, ethyl, propyl, i-propyl, butyl, s-butyl, t-butyl, straight or branched pentyl, or straight or branched hexyl; each of which is optionally substituted; each R is independently hydrogen, C 1-6 aliphatic, C 3-10 aryl, a 3-8 membered saturated or partially unsaturated carbocyclic ring, a 3-7 membered heterocylic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a 5-6 membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; each of which is optionally substituted; or two R groups on the same atom are taken together with the atom to which they are attached to form a C 3-10 aryl, a 3-8 membered saturated or partially unsaturated carbocyclic ring, a 3-7 membered heterocylic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a 5-6 membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; each of which is optionally substituted; k is 1; n is 0, 1, or 2; p is 0, 1, or 2 r is 0; and t is 1. Ring B is R 1 is -CH 3, -CF 3, -CN, -OCH 3, or -OCF 3; each R 2 is independently -H, -R, halogen, -haloalkyl, -OR, -SR, -CN, -NO 2, -SO 2 R, -SOR, -C R, -CO 2 R, -C N 2, -NRC R, -NRC N 2, -NRSO 2 R, or -N 2; each R 3 is independently -H, -R, halogen, -haloalkyl, -OR, -SR, -CN, -NO 2, -SO 2 R, -SOR, -C R, -CO 2 R, -C N 2, -NRC R, -NRC N 2, -NRSO 2 R, or -N 2; X is -CH 2 -; Y is C(R 4) 2 or NR 4; each R 4 is independently -H, -R, halogen, -haloalkyl, -OR, -SR, -CN, -NO 2, -SO 2 R, -SOR, -C R, -CO 2 R, -C N 2, -C R, -C NR 2, -NRC R, -NRC N 2, - NRSO 2 R, or -N 2; R 5 is independently methyl, ethyl, ethyl, propyl, i-propyl, butyl, s-butyl, t-butyl, straight or branched pentyl, or straight or branched hexyl; each of which is optionally substituted; each R is independently hydrogen, C 1-6 aliphatic, C 3-10 aryl, a 3-8 membered saturated or partially unsaturated carbocyclic ring, a 3-7 membered heterocylic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a 5-6 membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; each of which is optionally substituted; or two R groups on the same atom are taken together with the atom to which they are attached to form a C 3-10 aryl, a 3-8 membered saturated or partially unsaturated carbocyclic ring, a 3-7 membered heterocylic ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a 5-6 membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; each of which is optionally substituted; k is 1; n is 0, 1, or 2; p is 0, 1, or 2 r is 0; and t is 1.