Patent ID: 6861532

Claim:
A method of preparing a 2-alkylated cysteine represented by Structural Formula (I): or salts thereof; wherein R 2 is a substituted or unsubstituted alkyl group; comprising the steps of: a.) reacting a compound represented by Structural Formula (II): with a substituted or unsubstituted aryl nitrile of the formula Ar—CN in the presence of a secondary or tertiary amine base, wherein Ar is a substituted or unsubstituted aryl group, thereby forming a substituted thiazoline represented by Structural Formula (III): b.) alkylating the substituted thiazoline with one or more bases and R 2 X, wherein X is a leaving group and R 2 is as defined above; thereby forming an alkylated substituted thiazoline represented by Structural Formula (IV): c.) reacting the alkylated substituted thiazoline with acid, thereby forming the 2-alkylated cysteine represented by Structural Formula (I).