THE SYNTHESIS OF ALANYL-α-AMINOPROPIONITRILES-( Dl-dl , L-DL , and L-L ) BY DEHYDRATING THE CORRESPONDING N-o-NITROPHENYLSULFENYLALANYLALANINE AMIDES

N-o-Nitrophenylsulfenylalanylalanine amides(Dl-dl, L-DL, and L-L) were dehydrated In POCl3-pyridine without affecting their N-protecting groups. The N-protected dipeptide nitriles obtained were treated with anhydrous HCl in ethyl acetate to give the hydrochlorides of the corresponding dipeptide nitriles. The results of ion exchange chromatography of these products Indicated that the optical purity of the α-aminopropionitrile group was well retained.