The investigation of the inhibition effects of 5 ? amino -1, 3, 4-thiadiazole derivatives on human carbonic anhydrase enzyme

In this study, new carbonic anhydrase inhibitors?s effects on carbonic anhydrase enzyme as candidates for treatment of glaucoma were investigated.Firstly, erythrocyte carbonic anhydrase isoenzymes (HCA-I,HCA-II) from human erythrocyte were separately purifed by affinity chromatography.Later, inhibition effects of these new compounds (11, 12, 13) on human carbonic anhydrase enzymes (HCA) were investigated in vitro. In the studies, it was taken advantage of hydrates and esterase activites for determining of carbonic anhydrase activitates. It was observed that (11, 12, 13) compounds show inhibition effect on HCA hydratase and esterase activity. I50 values were determined by drawing % activity-[I] graphs for drugs showing inhibition effects. For CO2-hydratase activity compounds of (11), (12), (13)inhibition effect ranged from 0,8.10-7 to 1,09.10-7 M for HCA-II with I50 (molarity of inhibitor producing a %50 inhibition of CA activity).As for esterase activity of p-nitrophenyl acetate, (11), (12), (13) compounds had inhibition ranging from 1,0.10-7 to 3,2.10-7 M for HCA-II with I50.