Patent ID: 7795450

Claim:
A compound of the formula: wherein: R 1 , R 2 and R 5 are independently selected from the group consisting of H and C 1 -C 2 alkyl; R 3 and R 4 are selected from C 2 -C 8 alkyl; R 6 is the L-isomer (amino acid convention) of R 7 —(CH 2 ) n —HC(NH 2 )—CO—; wherein n is an integer from 0 to 3; R 7 is selected from the group consisting of unsubstituted heteroaryl and monosubstituted heteroaryl, wherein said heteroaryl is indolyl, and said substituent is hydroxy, halo, amino, nitro, methyl or acetoxy; X is independently selected in each instance from the group consisting of trans, trans>C═CH—HC═C<, trans>C═C<, and >C*H—(CH 2 ) m —HC*<, where “*” indicates a chiral carbon atom and R 3 and R 4 are oriented L- and D- (amino acid convention) at these respective chiral centers; and m=0, 1 or 2, or a pharmaceutically acceptable salt, solvate or prodrug thereof.