Patent ID: 7015305

Claim:
A process for preparing a compound of formula I: wherein R 1 is selected from the group consisting of C 1-10 alkylene, C 2-10 alkenylene and C 2-10 alkynylene; R 2 is selected from the group consisting of C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, C 3-8 cycloalkyl, C 5-8 cycloalkenyl, C 6-10 aryl, C 2-9 heteroaryl, C 2-9 heterocyclic, —R a -Cy 1 , —R a -Ar 1 -Ar 2 , —R a -Ar 1 -R b -Ar 2 , —R a -Ar 1 -O—R b -Ar 2 ; R a is selected from the group consisting of C 1-10 alkylene, C 1-10 alkenylene and C 1-10 alkynylene; R b is selected from the group consisting of C 1-6 alkylene, C 1-6 alkenylene and C 1-6 alkynylene; Cy 1 is selected from the group consisting of C 3-8 cycloalkyl, C 5-8 cycloalkenyl, C 6-10 aryl, C 2-9 heteroaryl, C 2-9 heterocyclic; Ar 1 and Ar 2 are independently selected from C 6-10 aryl and C 2-9 heteroaryl; wherein each aryl, heteroaryl and heterocyclic group is optionally substituted with 1 to 3 substituents independently selected from the group consisting of C 1-6 alkyl, C 1-6 alkoxy, halo, hydroxy, nitro and trifluoromethyl, and each heteroaryl and heterocyclic group contains from 1 to 3 heteroatoms selected from nitrogen, oxygen or sulfur; or salts thereof; the process comprising: (a) combining vancomycin or a salt thereof, with a compound of formula II: wherein R 1 and R 2 are as defined herein; and R 3 is a amine-labile protecting group; in the presence of a base to form a reaction mixture; (b) acidifying the reaction mixture from step (a) with an acid; (c) contacting the reaction mixture from step (b) with a reducing agent; (d) contacting the reaction mixture from step (c) with an amine, to provide a compound of formula I or a salt thereof.