Patent ID: 7323601

Claim:
A compound of the formula I, or a pharmaceutically acceptable salt, prodrug or isomer thereof: wherein X 1 is H, R 1 , R 2 , OR 2 , NR 1 R 2 , or S(O) a R 2 , where a is an integer selected from 0, 1, 2, or 3; X 2 is H, R 3 , R 4 , OR 4 , NR 3 R 4 , or S(O) a R 4 , where a is an integer selected from 0, 1, 2, or 3; X 3 is (CH 2 ) b , where b is an integer selected from 0, 1, 2, 3, or 4; X 4 is (CH 2 ) c , where c is an integer selected from 0, 1, 2, 3, or 4; R 1 is a straight-chain or branched alkyl having 12 to 20 carbon atoms or a straight-chain or branched alkenyl group having 12 to 20 carbon atoms; R 2 is H, a straight-chain or branched alkyl having 12 to 20 carbon atoms or a straight-chain or branched alkenyl group having 12 to 20 carbon atoms; R 3 is a straight-chain alkyl group having 1 to 3 carbon atoms, or a branched or cyclic alkyl group having 3 carbon atoms; R 4 is H, a straight-chain alkyl group having 1 to 3 carbon atoms, or a branched or cyclic alkyl group having 3 carbon atoms; R 5 is (CH 2 ) m where m is an integer selected from 0, 1, 2, 3, or 4; Z is H, X 5 is N or As; R 6 and R 7 are each independently hydrogen, a straight-chain alkyl group having 1 to 3 carbon atoms, or a branched or cyclic alkyl group having 3 carbon atoms; and R 8 is hydrogen, a straight-chain alkyl group having 1 to 3 carbon atoms or a branched or cyclic alkyl group having 3 carbon atoms.