Patent ID: 7186797

Claim:
A compound having the formula: wherein R 1 is (CH 2 ) n , where n is an integer from 0 to 12; R 2a and R 2b are independently (CH 2 ) m , C(O)NH—(CH 2 ) x , CH 2 —NH—(CH 2 ) y , (CH 2 ) z —C(O), or not present, where m, x, and z are integers from 0 to 12 and y is an integer from 1 to 12; R 3 is independently C(O)—(CH 2 ) p , where p is an integer of 0 to 12, C(O)CH(CH 3 ), C(O)C(CH 3 ) 2 , or is not present; R 4 is H, alkyl, or a negative charge and the salts thereof; X is N, CH, P, or triazine; W′ is a linear or branched alkyl chain having one or more carbon atoms; and R 5 is halogen, 1° amine, 2° amine, 3° amine, hydroxyl, thiol, carboxylic acid, sulfonic acid, or activated ester.