Patent ID: 8450307

Claim:
A compound of formula I: wherein, independently for each occurrence, A is a monocyclic ring of 4-7 atoms containing 0-2 heteroatoms, a bicyclic ring of 8-12 atoms containing 0-4 heteroatoms or a tricyclic ring of 8-12 atoms containing 0-6 heteroatoms wherein the rings are independently aliphatic, aromatic, heteroaryl or heterocyclic in nature, the heteroatoms are selected from N, S or O and the rings are optionally substituted with one or more groups selected from C 1-4 alkyl, OR″, CN, OCF 3 , F, Cl, Br, I; wherein R″ is H, alkyl, aralkyl, or heteroaralkyl; R is wherein, independently for each occurrence, R 1 is H, alkyl, or aryl; R 2 and R 3 taken together form a spirocyclic ring, wherein the spirocyclic ring is a 3-10 membered cycloalkyl ring, or a 3-10 membered saturated or unsaturated heterocyclic ring containing 1-4 heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur; R 5 is H, alkyl, or aryl; R 6 is H, alkyl, or aryl; and L 1 is O or H 2 ; or a pharmaceutically acceptable salt thereof.