Patent ID: 7700612

Claim:
A di-ester compound having the following structure: wherein R 1 , R 2 , R 3 , and R 4 , which can be the same or different, are hydrogen, halogen, C 1 -C 20 alkyl, C 1 -C 8 alkoxyl, C 4 -C 20 aryl or C 1 -C 20 silyl, R, which can be the same or different, is C 2 -C 30 alkyl, C 2 -C 22 alkenyl, C 4 -C 30 aryl, (CH 2 ) n OR 5 , (CH 2 ) n SR 5 , (CH 2 ) n NR 5 R 6 or (CH 2 ) n COR 7 , R 5 and R 6 , which can be the same or different, are C 1 -C 8 alkyl or C 2 -C 6 alkenyl, R 7 is hydroxy, C 1 -C 20 alkyl, C 1 -C 6 alkenyl, C 1 -C 6 alkoxy, C 4 -C 20 aryl, or NR 8 R 9 , R 8 and R 9 , which can be the same or different, are C 1 -C 6 alkyl, and n is an integer of 1 to 8, or a pharmaceutically acceptable salt thereof.