Investigation of the Effect of Some Optically Active Imine Compounds on the Enzyme Activities of hCA-I and hCA-II under In Vitro Conditions: An Experimental and Theoretical Study

Abstract

Inhibitors of carbonic anhydrase (hCA; EC 4.2.1.1) are used as medicines for many diseases. Therefore, they are very important. In this study, a known series of Schiff bases were synthesized and their effects on the activities of hCA-I and hCA-II, which are cytosolic isoenzymes of carbonic anhydrase, were investigated under in vitro conditions. The synthesized compounds (H1, H2, H3, and H4) were found to cause inhibition on enzyme activities of hCA-1 and hCA-II. IC50 values of H1, H2, H3, and H4 compounds were 140, 88, 201, and 271 M for hCA-I enzyme activity and 134, 251, 79, and 604 M for hCA-II enzyme activity, respectively. The synthesized Schiff bases were characterized by several methods, including H-1 NMR, FT-IR, elemental analysis, and polarimetric measurements. Correlation coefficient square values (R-2) of comparison of the theoretical and experimental H-1 NMR shifts for H1, H2, H3, and H4 compounds were found as 0.9781, 0.9814, 0.9758, and 0.8635, respectively.