Microwave assisted solvent-free mannich bases: synthesis, characterization and effects of these compounds on HCA I and HCA II isozymes

Abstract

Mannich bases (2a–d) of aromatic amines were synthesized by using a conventional microwave technique under solvent-free conditions and characterized by IR and NMR (1H and 13C) and elemental analysis. The inhibitory effects of the synthesized Mannich bases were examined in vitro by using hydratase and esterase assays on carbonic anhydrase I and II isozymes (hCA, EC 4.2.1.1) purified from human erythrocyte cells. Acetazolamide was used as the control compound. The values of IC50, the half-maximum inhibitory concentration, were found for hydratase and esterase activities. Only two compounds (2b and 2d) exhibited poor hCA I and hCA II inhibition effects on esterase activity. In contrast, compounds 2a and 2c could be used as carbonic anhydrase activators as a result of the increased esterase activity of hCA I and hCA II isozymes.

Keywords

• Activator
• carbonic anhydrase
• glaucoma
• isozyme