Patent ID: 7241900

Claim:
A compound of the formula II wherein: R1 maybe hydrogen or can be selected from the group consisting of (C1–C6)-alkyl and (C3–C7)-cycloalkyl, and wherein the alkyl group can be substituted by (C3–C7)-cycloalkyl or can be mono- or polysubstituted by an aryl group, wherein the aryl group can be mono- or polysubstituted by halogen, (C1–C6)-alkyl, (C3–C7)-cycloalkyl, hydroxy and nitro groups; R1 may be an aryl, wherein the aryl group can be mono- or polysubstituted by halogen, (C1–C6)-alkyl, (C3–C7)-cycloalkyl, hydroxy and nitro groups; R1 may further be a protecting group; R2, R3, R4, R5, R6, and R7 may be the same or different and are each selected from the group consisting of hydrogen, (C1–C6)-alkyl, (C3–C7)-cycloalkyl, (C1–C6)-acyl, (C1–C6)-alkoxy, alkoxycarbonyl (COOR1) halogen, benzyloxy, the nitro group, the amino group, the (C1-C4)-mono or dialkyl-substituted amino group, or an aryl group, wherein the aryl group can be mono- or polysubstituted by halogen, (C1–C6)-alkyl, (C3–C7)-cycloalkyl, hydroxy and nitro groups; X and Z may be the same or different and are each selected from the group consisting of O, S and NH; and wherein the stereochemical centers, i,e., the carbons bearing C(X)ZR1 and R7 substituent may have R or S configuration.