Patent ID: 7300940

Claim:
A compound having the formula in which: X is a member selected from the group consisting of NH, O, and S; n is zero or a positive integer; R 1 is a member selected from the group consisting of CH 2 , NH, O, and S; R 2 is a member selected from the group consisting of CHR 7 , NR 7 , O, and S, in which R 7 is H or alkyl; R 3 and R 4 are members independently selected from the group consisting of H, alkyl, aryl, arylalkyl, cycloalkyl, cycloalkylalkyl, alkyl-substituted aryl, (alkyl-substituted aryl)alkyl, hydroxy-substituted alkyl, hydroxy-substituted aryl, and (hydroxy-substituted aryl)alkyl; R 5 is a member selected from the group consisting of CH 2 , NH, O, and S; R 6 is a member selected from the group consisting of H and C(═Y)—R 8 —R 9 , in which: Y is a member selected from the group consisting of NH, O, and S; R 8 is a member selected from the group consisting of CHR 10 , NR 10 , O, and S, in which R 10 is either H or alkyl; and R 9 is a member selected from the group consisting of H, alkyl, aryl, arylalkyl, cycloalkyl, cycloalkylalkyl, alkyl-substituted aryl, (alkyl-substituted aryl)alkyl, hydroxy-substituted alkyl, hydroxy-substituted aryl, and (hydroxy-substituted aryl)alkyl.