N‐ACYLSUCCINIMIDES AS ACYLATING AGENTS FOR PROTEINS: SYNTHESIS, HYDROLYSIS AND AMINOLYSIS

Abstract

N‐Acylsuccinimides have been examined as potential acylating agents. Three different methods used to synthesize a number of these reagents are described. The rates of hydrolysis of N‐acetyl, N‐propionyl, N‐n‐butyryl, N‐i‐butyryl and N‐n‐valeryl succinimides and the rates at which they react with n‐butylamine in aqueous solution are reported. These N‐acylsuccinimides are soluble in water, relatively slow to hydrolyse and yet sufficiently reactive to acylate amines in aqueous solution, even in weak acid solutions. The hydrolysis of N‐acetylsuccinimide follows two pathways, giving, as primary products, either N‐acetylsuccinamic acid or acetic acid and succinimide. The relative amounts of these hydrolysis products, which were determined by NMR spectroscopy, varies with the pH of hydrolysis.