Peptide Synthesis in Aqueous Solution. IV. Preparation and Properties of [p-(Benzyloxycarbonyloxy)phenyl]dimethylsulfonium Methyl Sulfate (Z-ODSP), [p-(t-Butoxycarbonyloxy)phenyl]dimethylsulfonium Methyl Sulfate (Boc-ODSP) and [p-(9-Fluorenylmethyloxycarbonyloxy)phenyl]dimethylsulfonium Methyl Sulfate (Fmoc-ODSP) as Water-Soluble N-Acylating Reagents

Abstract

Abstract In order to increase the applications of the water-soluble active ester method, water-soluble acylating reagents, [p-(benzyloxycarbonyloxy)phenyl]dimethylsulfonium methyl sulfate, [p-(t-butoxycarbonyloxy)phenyl]dimethylsulfonium methyl sulfate and [p-(9-fluorenylmethyloxycarbonyloxy)phenyl]dimethylsulfonium methyl sulfate, were synthesized from of p-hydroxyphenyldimethylsulfonium methyl sulfate. These compounds had high solubility (more than 30%) in water and were found to act as excellent water-soluble acylating reagents for the synthesis of N-benzyloxycarbonyl, N-t-butoxycarbonyl, N-9-fluorenylmethyloxycarbonyl amino acid derivatives in aqueous solution. They converted dipeptides to N-acyl-dipeptides in aqueous media as well as amino acids. In addition, they were found to be efficient reagents for protecting the side chains of lysine, ornithine, and cysteine.