QM study the inhibitory effect of Bisulfite Ion on inhibition of carbonic enzyme

The theory of density function, a theory in the framework of quantum mechanics to study the electron structure with basic set B3LYP/6311++G** computation has been used to optimized the structures of bisulfite ion and complex between these inhibitors with active site of α-CA enzyme. The anion of bisulfite is coordinate to the zinc as five ligand in intermediate complex.Acoording to calculated results thiocyanate and isothiocyanate with more negative thermpdynamic functions are more effective than the others drugs to control some dieses like of cancer. PCM method used for solvent effects in all calclutions. Keywords: Anionic inhibitor, Anti-cancer, Carbonic anhydrase, DFT.