Microwave irradiation and COMU: a potent combination for solid-phase peptide synthesis

Here we demonstrate the compatibility of Oxyma-based uronium-type coupling reagent COMU with microwave-assisted peptide synthesizers. Consistent with previous reports, COMU displayed higher efficiency than benzotriazole classical immonium salts HATU and HBTU in the demanding synthesis of the Aib derivative of Leu-Enkephalin pentapeptide and did not yield Oxyma-based byproducts. Thus, the combination of microwave irradiation and COMU resulted in a similar performance in considerably shorter time to that achieved by manual synthesis.