The Facile Production of N -Methyl Amino Acids via Oxazolidinones

A range of oxazolidinones derived from N -carbamoyl a-amino acids were prepared by an efficient method as key intermediates in the synthesis of N -methyl amino acids and peptides. The method was readily applied to most a-amino acids except those with basic side chains. The oxazolidinones were converted by reductive cleavage into N -methyl a-amino acids.