An improved practical synthesis of protected α-amino selenocarboxylates and its application to the synthesis of N-(α-aminoacyl)sulfonamides

An improved practical synthetic method was developed for the preparation of selenocarboxylates of amino acids through the reaction of the corresponding activated esters with sodium hydrogen selenide in alcoholic or aqueous medium. The protected α-amino selenocarboxylates reacted readily with sulfonyl azide to form N-(α-aminoacyl)sulfonamides in high yields. The commonly used protecting groups in amino acid and peptide chemistries are well tolerated under these reaction conditions. No protecting groups are needed for the side chains of Arg, Met, Ser, Tyr, and Trp.