The N-phosphobiotin route: a possible new pathway for biotin coenzyme

Abstract

The formation of N-acylureas from N-phosphorylated ureas under very mild conditions is presented as a possible route to formation of carboxybiotin from biotin in biotin-mediated enzymatic carboxylations in which an N-phosphobiotin is the activated form. The detailed mechanistic pathway for the model reaction indicates that an intermediate acylphosphate is formed, the rate-determining step being nucleophilic attack of the ureido anion or its enol on this acylphosphate. In no case was an O-phosphorylated intermediate (of the O-phosphobiotin type) involved.