Patent ID: 8389555

Claim:
A compound of formula (I): wherein R 1 is selected from the group consisting of substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted alkoxy, substituted or unsubstituted amino, substituted or unsubstituted carbocyclic ring, and substituted or unsubstituted heterocyclic ring; and R 2 comprises a polar moiety, P, and at least one linking group, Z, linking the polar moiety, P, to the nitrogen of the NR 1 group; and wherein said at least one linking group, Z, is selected from one or more of the group consisting of substituted or unsubstituted C 2 -C 6 alkylene, substituted or unsubstituted C 2 -C 6 alkenylene, substituted or unsubstituted C 2 -C 6 alkynylene, substituted or unsubstituted carbocyclic ring, and substituted or unsubstituted heterocyclic ring; and wherein said polar moiety, P, comprises a heteroatom selected from the group consisting of oxygen, sulfur, and nitrogen.