Metal based drugs: design, synthesis and in-vitro antimicrobial screening of Co(II), Ni(II), Cu(II) and Zn(II) complexes with some new carboxamide derived compounds: crystal structures of N-[ethyl(propan-2-yl)carbamothioyl]thiophene-2-carboxamide and its copper(II) complex

Abstract

A new series of compounds derived from thiophene-2-carboxamide were synthesized and characterized by IR, ¹H-NMR and ¹³C-NMR, mass spectrometry and elemental analysis. These compounds were further used to prepare their Co(II), Ni(II), Cu(II) and Zn(II) metal complexes. All metal(II) complexes were air and moisture stable. Physical, spectral and analytical data have shown the Ni(II) and Cu(II) complexes to exhibit distorted square-planar and Co(II) and Zn(II) complexes tetrahedral geometries. The ligand (L¹) and its Cu(II) complex were characterized by the single-crystal X-ray diffraction method. All the ligands and their metal(II) complexes were screened for their in-vitro antimicrobial activity. The antibacterial and antifungal bioactivity data showed that the metal(II) complexes were found to be more potent than the parent ligands against one or more bacterial and fungal strains.

• Antibacterial
• antifungal
• carboxamides
• crystal structures
• metal(II) complexes

Acknowledgements

The authors are thankful to HEJ research Institute of Chemistry, University of Karachi, Pakistan, for providing their help in taking NMR, mass spectral and antibacterial/antifungal data.

Declaration of interest

This work was supported by Collaboration between University of Manchester, UK and Bahauddin Zakariya University, Multan (Pakistan) on Indigenous Fellowship program sponsored by the Higher Education Commission, Government of Pakistan to one of the authors (MH).

Supplementary material available online

Supplementary Tables S1-S8.