Patent ID: 8686145

Claim:
A process for preparing a compound of formula I: comprising: a) reacting a compound of formula II: with a compound of formula III: R 2 â€”COOHâ€ƒâ€ƒ(III), and a compound of formula IV: R 3 â€”NCâ€ƒâ€ƒ(IV), under such conditions that a compound of formula I is formed, wherein R 1 represents a substituted or unsubstituted alkyl, alkenyl, alkynyl, aromatic or non-aromatic, mono-, di- or tricyclic, or heterocyclic group, R 2 represents a substituted or unsubstituted alkyl, alkenyl, alkynyl, aromatic or non-aromatic, mono-, di- or tricyclic, or heterocyclic group, and R 3 represents a substituted or unsubstituted alkyl, alkenyl, or alkynyl group, or a reversibly attached protective group.