Synthesis and characterization of complexes of a novel proton transfer salt and their inhibition studies on carbonic anhydrase isoenzymes

Abstract

A novel proton transfer compound (HClABT)⁺(HDPC.H₂DPC)⁻ (1) and its Fe(III), Co(II), Ni(II) and two different Cu(II) complexes (2–6) have been prepared and characterized by spectroscopic techniques. Additionally, single crystal X-ray diffraction techniques were applied to all complexes. All compounds, including acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibition effects on human hCA I and hCA II for their hydratase and esterase activities. Although there is no inhibition for hydratase activities, all compounds have inhibited the esterase activities of hCA I and II. The comparison of the inhibition studies of 1–6 to parent compounds, ClABT and H₂DPC, indicates that 1–6 have superior inhibitory effects. The inhibition effects of 2–6 are also compared to the inhibitory properties of the simple metal complexes of ClABT and H₂DPC, revealing an improved transfection profile. Data have been analysed by using a one-way analysis of variance for multiple comparisons.

• 2-Amino-6-chlorobenzothiazole
• 2,6-pyridinedicarboxylic acid
• carbonic anhydrase
• proton transfer
• statistical analyses

Acknowledgements

The authors would like to thank the Medicinal Plants and Medicine Research Center of Anadolu University Eskişehir for allowing to use the X-ray facility.

Declaration of interest

The authors acknowledge the support provided by Dumlupýnar University Research Fund (grant No. 2012/16).

Supplementary material available online

Supplementary Tables and Figures S1--S7