Patent ID: 7728104

Claim:
A process for preparing a hydrochloride salt of a compound of formula I: the process comprising, (a) combining vancomycin, or a salt thereof, with a compound of formula II: in the presence of 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 IV: or a salt thereof; wherein steps (a), (b), (c) and (d) are conducted in the same reaction mixture without isolation of the intermediate from step (a), (b) or (c); (e) reacting the compound of formula IV, or a salt thereof, with formaldehyde and a compound of formula V: in the presence of a base; (f) acidifying the reaction mixture from step (e) to a pH in the range of from 2 to 3 with hydrochloric acid; and (g) adding acetonitrile to the reaction mixture from step (F) to precipitate a hydrochloride salt of the compound of formula I.