AN IMPROVED PROCESS FOR PREPARATION OF ALANINE-NCA

摘要

Alanine-N-carboxy anhydride (Tyrosine-NCA, I) is one of the four amino acid building blocks used in the preparation of glatiramer acetate. The present invention describes a process for preparation of alanine-NCA by industrially convenient, environmentally friendly and safe process involving the reaction of triphosgene and tyrosine. Alanine-NCA obtained by this process is > 99.0% pure with <0.01% chloride content and substantially free from tyrosine impurity.