Phosphinyl- and Phosphinothioylamino Acids and Peptides. VI. The Protection of the Hydroxyl Function in the Tyrosine Side-chain by the Dimethylphosphinothioyl Group

Article abstract of DOI:10.1246/bcsj.55.204

The use of the dimethylphosphinothioyl (Mpt) group for the protection of the hydroxyl function in the tyrosine side-chain was studied. N,O-Bis(Mpt)tyrosine was obtained directly by a Schotten-Baumann-type reaction of Mpt-Cl with tyrosine. The O-Mpt group was stable under acidic conditions, and it could be removed easily by alkaline hydrolysis or ester-exchange reaction. The usefulness of this new protecting group for the peptide synthesis was shown in the solid-phase synthesis of 2,L-Leu⁵>-enkephalin(H-L-Tyr-D-Ala-Gly-L-Phe-L-Leu-OH) and its N-allyl derivative.