Synthesis, characterization, crystal structure of the coordination polymer Zn(II) with thiosemicarbazone of glyoxalic acid and their inhibitory properties against some metabolic enzymes

A new coordination polymer Zn(II) with thiosemicarbazone glyoxalic acid H(2)GAT was obtained in this study. According to the X-ray diffraction data, the coordination of the Zn(II) ion is carried out by one sulfur atom, in the thiol form, one nitrogen atom of the azomethine group and two oxygen atoms of the carboxylate groups, one of which belongs to neighbouring complex molecule. The oxygen atom of the water molecule completes Zn(II) ion environment to a distorted square-pyramidal structure. The binding of the monomer complex into polimer occurs through the bridge oxygen atom of carboxylate group. This complex is effective inhibitor of the alpha-glycosidase, butyrylcholinesterase (BChE), cytosolic carbonic anhydrase I and II isoforms (hCA I and II), and acetylcholinesterase enzymes (AChE) enzymes with Ki values of 1.45 +/- 0.23 mu M for hCA I, 2.04 +/- 0.11 mu M for hCA II, 3.47 +/- 0.88 mu M for alpha-glycosidase, 0.47 +/- 0.10 mu M for BChE, and 0.58 +/- 0.13 mu M for AChE, respectively

Synthesis, characterization, crystal structure, electrochemical studies and biological evaluation of metal complexes with thiosemicarbazone of glyoxylic acid

Cobalt and nickel nitrates form with thiosemicarbazone of glyoxylic acid (H(2)GAT) complexes of empirical composition Co(C3H4N3O2S)(2)center dot 2H(2)O, Ni(C3H4N3O2S)(2)center dot 2H(2)O and Ni(C3H6N3O2S)(2). X-ray diffraction studies have shown that the Co(HGAT)(2)center dot 2H(2)O, Ni(HGAT)(2)center dot 2H(2)O complexes are mononuclear, in which the coordination around the metal is octahedral, made up of two sulfur atoms, two nitrogen atoms and two oxygen atoms from two ligands. By the interaction of NiCl2 center dot H2O with 2-[2-(aminothioxomethyl)hydrazinyl] acetic acid (H(2)TAA) instead of the expected the metal thiosemicarbazonate complex with the hydrogenated on the azomethine group ligand was obtained. The redox properties of these compounds were also investigated by voltammetry on Pt in dimethylsulfoxide/tetrabutylammonium perchlorate. These thiosemicarbazone of glyoxylic acid derivatives had effective inhibition against alpha-glycosidase, cytosolic carbonic anhydrase I and II isoenzymes, butyrylcholinesterase and acetylcholinesterase. K-i values were found as 26.12-36.58 nM for hCA I, 20.73-40.78 nM for hCA II, 184.30-642.18 nM for AChE, 123.67-342.37 nM for BChE, and 14.66-45.62 nM for alpha-glycosidase. (C) 2018 Elsevier Ltd. All rights reserved