Patent ID: 6855695

Claim:
A compound or its pharmaceutically acceptable salt of the structure: Where R is —CH 3 or —CH 2 CH 2 Cl; R′ is C 1 -C 7 alkyl or —CH 2 CH 2 Cl; one of R 2 or R 4 , but not both, is selected from OPO 3 H 2 , NO 2 , OCO(Glu), NHCO(Glu) and NHR 7 and the other of R 2 or R 4 which is unassigned, and R 3 , R 5 and R 6 , are, independently selected from H, F, Cl, Br, I, OH, OPO 3 H 2 , OCH 3 , CF 3 , OCF 3 , NO 2 , CN, SO 2 CH 3 , SO 2 CF 3 , COCH 3 , COOCH 3 , SCH 3 , SF 5 , NHR 8 , N(R 9 ) 2 and C 1 -C 7 alkyl, with the proviso that at least two of R 2 , R 3 , R 4 , R 5 and R 6 are H; R 7 is H, glutamyl or a polyglutamic acid polypeptide residue —OCH(NHR 7a )CH 2 CH 2 CO 2 H where R 7a is glutamyl or a polyglutamic acid polypeptide residue having from 1 to 50 peptide linkages; R 8 is H or C 1 -C 7 alkyl; and R 9 is CH 3 or CH 2 CH 3 .