Patent ID: 7129261

Claim:
A compound having the structure: or a pharmaceutically acceptable salt thereof; wherein X and Z are members independently selected from O, S and NR 23 wherein R 23 is a member selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, and acyl; R 1 is H, substituted or unsubstituted lower alkyl, or C(O)R , wherein R 8 is a member selected from NR 9 R 10 and OR 9 , in which R 9 , and R 10 are members independently selected from H, substituted or unsubstituted alkyl and substituted or unsubstituted heteroalkyl; R 2 is H or lower alkyl; R 3 is a member selected from (═O), and OR 11 , wherein R 11 is a member selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, acyl, C(O)R 12 R 13 , C(O)OR 12 , C(O)NR 12 R 13 , P(O)(OR 12 ) 2 , C(O)CHR 12 R 13 , and SiR 12 R 13 R 14 , in which R 12 , R 13 , and R 14 are members independently selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl and substituted or unsubstituted aryl, wherein R 12 and R 13 together with the nitrogen atom to which they are attached are optionally joined to form a substituted or unsubstituted heterocycloalkyl ring system having from 4 to 6 members, optionally containing two or more heteroatoms; R 4 and R 5 are members independently selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heterocycloalkyl, halogen, NO 2 , NR 15 R 16 , NC(O)R 15 , OC(O)NR 15 R 16 , OC(O)OR 15 , C(O)R 15 , OR 15 wherein R 15 R 16 are independently selected from H, substituted or unsubstituted alkyl, substituted or unsubstituted heteroalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, and substituted or unsubstituted heterocycloalkyl, wherein R 15 and R 16 together with the nitrogen atom to which they are attached are optionally joined to form a substituted or unsubstituted heterocycloalkyl ring system having from 4 to 6 members, optionally containing two or more heteroatoms; R 6 is a single bond which is either present or absent and when present R 6 and R 7 are joined to form a cyclopropyl ring; and R 7 is CH 2 —X 1 or —CH 2 — joined in said cyclopropyl ring with R 6 , wherein X 1 is a leaving group; wherein at least one of R 4 , R 5 , R 11 , R 12 , R 13 , R 15 , and R 16 has one or more cleavable groups, wherein the cleavable group is selected from peptides, amino acids, and disulfides.