Patent ID: 7923013

Claim:
A compound represented by the structure of formula 1: wherein, R=COOR 1 or CH 2 OR 1 ; R 1 =H or an alkyl group; R 2 =H or SO 3 − ; R 3 =H or OH; R 3 ′=H or OH; R 4 and R 4 ′ are independently chosen from (a) H, (b) alkyl; (c) alkenyl; and (d) oxaalkyl; R 5 =OH, acetamido or a halogen atom; or a pharmaceutically acceptable salt thereof, wherein if R=CH 2 OR 1 where R 1 is H, then R 2 ═SO 3 − , and wherein if R=CH 2 OR 1 , R 2 ═H, R 3 is OH and R 3 ′ is H, then R 5 =acetamido or a halogen atom.