Original enzyme-catalyzed synthesis of chalcones: Utilization of hydrolase promiscuity

Abstract

E-chalcone was obtained with very high stereoselectivity for the first time by an enzyme-catalyzed Claisen-Schmidt condensation between benzaldehyde and acetophenone. From a set of lipases, only that from hog pancreas demonstrated promiscuity, catalyzing the reaction in the presence of imidazole as a promoter. Another enzyme, acylase from Aspergillus melleus (3.5.1.14) also proved to be active in the synthesis of E-chalcone under the same reaction conditions. This acylase along with the recombinant D-aminoacylase (3.5.1.81) catalyzed also the reaction between acetophenone and p-nitrobenzaldehyde. Such “green” approach to synthesis of chalcones is of great interest, because of their important applications as formula ingredients in pharmaceutical, food and cosmetic industry.

Keywords

• Claisen-Schmidt condensation
• enzyme promiscuity
• Lipase-catalyzed synthesis