Patent ID: 8669264

Claim:
A compound of the following structure: or salts, hydrates or solvates thereof; wherein, at least one of R 1 -R 5 or R 8 is an independently selected electron withdrawing group; R 6 is an independently selected electron withdrawing group selected from the group consisting of F, I, nitro, acyl, formyl, an alkylsulfonyl having from 1 to 4 carbon atoms, an arylsulfonyl having from 6 to 15 carbon atoms, a fluoromethyl, and cyano group; R 7 is an independently selected electron withdrawing group selected from the group consisting of F, Br, I, nitro, acyl, formyl, an alkylsulfonyl having from 1 to 4 carbon atoms, an arylsulfonyl having from 6 to 15 carbon atoms, a fluoromethyl, and cyano group; and, the remainder of R 1 -R 7 or R 8 is hydrogen, a (C 1 -C 4 ) alkyl group, or a substituted (C 1 -C 4 ) alkyl group.