Patent ID: 7135483

Claim:
A compound having the structure; wherein: (a) A 1 and A 2 are each, independently, selected from the group consisting of a hydrogen atom and a group having the structure: with the proviso that at A 1 and A 2 are not both hydrogen atoms, and wherein: (i) each R 1 is independently selected from the group consisting of a hydrogen atom and a hydroxyl group; (ii) x is 0 or 1; (iii) each R 2 is independently selected from the group consisting of; wherein; (a) a is 2 to 10; (b) b is 2 to 10; (c) c is 1 to 3; (d) d is 1 to 3; and (e) R 12 and R 13 are each independently selected from the group consisting of hydrocarbon groups and substituted hydrocarbon groups; and (iv) D 1 is —C(O)—; and, (v) D 2 is —NH—; and (b) A 3 has the structure: wherein: (i) each R 1 is independently selected from the group consisting of a hydrogen atom and a hydroxyl group; (ii) t is from 0 to 6; (iii) D 4 is —CH(R 1 )—; (iv) D 5 is —OR 6 ; and (v) R 6 is selected from the group consisting of a carbocyclic group, a substituted carbocyclic group, an aromatic group, and a substituted aromatic group.