Patent ID: 7091351

Claim:
A compound of formula III: wherein R 2 and R 3 are each independently H, (C 1 –C 3 )alkyl, halogen, (C 1 –C 3 )alkoxy, halo(C 1 –C 3 )alkyl, cyano, (C 2 –C 6 )alkanoyloxy or nitro; X 2 and X 3 are each independently OH 2 ; or no ligand is present on X 3 ; or taken together X 2 and X 3 form N,N-bidentate group consisting of N,N-bipyridine, N,N-bipyrimidine and phenanthroline, wherein the N,N-bidentate can be substituted with up to two groups that are independently (C 1 –C 3 )alkyl, halogen, (C 1 –C 3 )alkoxy, halo(C 1 –C 3 )alkyl, cyano, (C 1 –C 6 )alkanoyloxy, or nitro; Y is OH 2 or OSO 3 ; and Z is O, CH 2 , or CH 2 —CH 2 ; or a pharmaceutically acceptable salt thereof.