Patent ID: 7009049

Claim:
A method for the synthesis of an enantiomerically pure compound of Formula 107/203: where: R 1 is hydrogen, alkyl, aryl, alkylaryl, heteroaryl, alkylheteroaryl, substituted alkyl, substituted aryl, substituted alkylaryl, substituted heteroaryl or substituted alkylheteroaryl; R 2 is alkyl, oxaalkyl, aryl, alkylaryl, heteroaryl, alkytheteroaryl, substituted alkyl, substituted aryl, substituted alkylaryl, substituted heteroaryl or substituted alkylheteroaryl, R 5 , R 6 , R 7 and R 8 are independently hydrogen, hydroxy, alkyl, alkoxy, halogen, fluoroalkyl, nitro, cyano, substituted alkyl, amino, alkylamino, dialkylamino, alkylsulfonyl, alkylsulfonamido, sulfonamidoalkyl, sulfonamidoaryl, alkylthio, carboxyalkyl, carboxamido, aminocarbonyl, aryl or heretoaryl; and X is hydrogen or a protecting group, said method comprising the steps of: A) contacting isobutyl chloroformate with an enantiomerically pure compound of Formula 101: B) contacting the product of step A with a compound of Formula 103: to yield a compound of Formula 104: C) converting the compound of Formula 104 to a compound of Formula 105; D) contacting the compound of Formula 105 with an amine of the formula R 1 NH 2 to yield a compound of Formula 106 and E) contacting the compound of Formula 106 with a cyclo-dehydration reagent chosen from lithium hydroxide monohydrate, HMDS, phosphorous oxychloride, oxalyl chloride, thionyl chloride, Brugess' reagent, Ph 3 P/l 2 , and Vilsmeier reagent to yield the compound of Formula 107/203.