Patent ID: 7235587

Claim:
A compound of formula (I): wherein A and B are the same or different and are selected from the group consisting of oxygen, amino and sulfur; R 1 and R 3 are the same or different and are selected from the group consisting of C 1 -C 30 alkyl, C 2 -C 30 alkylene, C 2 -C 30 alkyne, C 3 -C 8 cycloalkyl, C 1 -C 30 substituted alkyl, C 3 -C 8 substituted cycloalkyl, C 2 -C 30 substituted alkylene, C 2 -C 30 substituted alkyne, aryl, substituted aryl, heteroaryl, heterocycloalkyl, substituted heteroaryl and substituted heterocycloalkyl; R 2 is selected from the group consisting of C 1 -C 30 alkyl, C 2 -C 30 alkylene, C 2 -C 30 alkyne, C 3 -C 8 cycloalkyl, C 1 -C 30 substituted alkyl, C 3 -C 8 substituted cycloalkyl, C 2 -C 30 substituted alkylene, C 2 -C 30 substituted alkyne; R 4 , R 5 , R 6 and R 7 are the same or different and are selected from the group consisting of C 1 -C 30 alkyl, C 2 -C 30 alkylene, C 2 -C 30 alkyne, C 3 -C 8 cycloalkyl, C 1 -C 30 substituted alkyl, C 3 -C 8 substituted cycloalkyl, C 2 -C 30 substituted alkylene, C 2 -C 30 substituted alkyne, aryl, substituted aryl, heteroaryl, heterocycloalkyl, substituted heteroaryl, substituted heterocycloalkyl, hydroxyl, ester, carboxy, cyano, amino, amido, sulfur and halo; and a, b, c and d are each in the range of 0 to 4.