A New Synthesis of Glutathione via the Thiazoline Peptide

Article abstract of DOI:10.1246/bcsj.53.2592

A convenient synthesis of glutathione (GSH) by the use of minimal protecting groups was investigated.N-Formyl-L-2-amino-4-cyanobutyric acid ethyl ester was condensed with ethyl L-cysteinylglycinate to give (4R)-2-<(3S)-3-ethoxycarbonyl-3-(formylamino)propyl>-4-(ethoxycarbonylmethylcarbamoyl)-2-thiazoline.This compound was saponified in aqueous acetone at -15- -20 deg C and subsequently treated with dilute H2SO4 (pH 4) to yield formylglutathione, whose formyl group was then hydrolyzed with 0.5 M (1M = 1 mol dm^-3) H2SO4 to give free GSH.For purification, this was changed to a copper thiolate, which was then decomposed with H2S to afford pure GSH.