NEW HYDROXYL PROTECTING GROUPS OF A SAFETY-CATCH TYPE REMOVABLE BY TEDUCTIVE ACIDOLYSIS

Abstract

New hydroxyl protecting group of a safety-catch type, i.e., 4-methylsulfinylbenzyloxycarbonyl (Msz) group for Tyr and 4-methylsulfinylbenzyl (Msob) ether for Thr, have been developed. O-Msz and O-Msob groups are stable under both acidic and basic conditions and can be removed by a one-pot reaction involving reductive acidolysis using tetrachlorosilane-trifluoroacetic acid (TFA)-scavengers. Using these new protecting groups, a 17 residue-peptide, γ-endorphin, was successfully synthesized by the efficient solid phase method.