Patent ID: 7091195

Claim:
A compound having a structure: wherein R 1 is selected from the group consisting of CO(C 1 –C 6 alkyl)NR 4 R 5 , COCH(C 6 H 5 )NR 4 R 5 , CO(C 1-6 alkyl)O(CH 2 CH 2 O) n C 1-3 alkyl, CH 2 OCO 2 C 1-6 alkyl, and CH 2 OCOC 1-6 alkyl, R 2 is selected from the group consisting of CH 2 C 6 H 5 , C 1 –C 6 alkylNR 4 R 5 , CH 2 OCOC 1 –C 6 alkyl, PO(OH) 2 , SO 3 H, CH(C 6 H 5 )NR 4 R 5 , (C 1 –C 6 alkyl)CO 2 R 4 , and (C 1 –C 6 alkyl)O(CH 2 CH 2 O)nC 1-3 alkyl, R 4 and R 5 , independently, are selected from the group consisting of hydrogen, C 1 –C 6 alkyl, CO(C 1 –C 6 alkyl), and aryl, or R 4 and R 5 can be taken together to form a 5 to 7 membered ring, and n is 1 to 10; and pharmaceutically acceptable salts thereof.