A kinetic study of the hydrolysis of N-acetyl dehydroalanine methyl ester.

Hydrolysis rates of N-acetyl dehydroalanine methyl ester (methyl 2-acetamidoacrylate) and related model compounds were measured in aqueous, organic and mixed aqueous media. Adding dimethylsulfoxide (DMSO) to water, retarded hydrolysis of the ester by a factor of 2 to 500, depending on the pH of the medium and concentration of DMSO. Ethanol also slowed hydrolysis, but the effect was not so pronounced. Related studies show that the acetamido group C-N bond of sodium 2-acetamido-acrylate is hydrolyzed only about 1/130 as fast as the ester group C-O bond. Aqueous dimethyl sulfoxide should by a useful medium for synthesis of peptide, amino acid and protein derivatives of N-acetyl dehydroalanine methyl ester.