Synthesis, crystal structures, and antimicrobial activity of copper(II) complexes derived from N′-(1-(pyridin-2-yl)ethylidene)isonicotinohydrazide

Abstract

Two mononuclear copper(II) compounds, [Cu(HL)₂](ClO₄)₂ · (H₂L)ClO₄ · 3H₂O (1) and [CuL₂] (2), where L is the monoanionic form of N′-(1-(pyridin-2-yl)ethylidene)isonicotinohydrazide (HL), have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination. Compound 1 contains a [Cu(HL)₂]²⁺ complex cation, a H₂L⁺ cation, three perchlorate anions, and three water molecules of crystallization. Compound 2 contains one neutral [CuL₂] complex molecule. The Cu atoms in the complexes are in octahedral coordination, with the hydrazone ligands coordinate to the Cu atoms through the pyridine N, imine N, and enolate O atoms. The effect of the compounds on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans was studied.

Keywords:

• Hydrazone
• copper complex
• crystal structure
• antimicrobial activity

Additional information

Funding

This research was supported by the Top-class foundation of Pingdingshan University (no. PXY-BSQD-2018006 and PXY-PYJJ-2018002).