Antimicrobial study of ruthenium and iridium half-sandwich complexes containing fluorenyl hydrazonothiazole derivative ligands

Abstract

A series of six new hydrazineyl-thiazolyl mononuclear complexes (1–6) of the type [(arene)M(κ² _(N∩N)-L)Cl] (M = Ru, Ir, arene: p-cymene or Cp* (pentamethyl cyclopentadienyl); L = bidentate substituted thiazolyl derivatives) have been synthesized and characterized. The complexes have been isolated as neutral mononuclear N∩N chelating metal complexes. Complexes 1–6 were characterized by IR, UV–Vis, NMR, and ESI-MS spectral methods. The solid-state molecular structures of 3 and 4 were determined using single-crystal X-ray diffraction and the geometry of the complexes are pseudo-octahedral, similar to piano stool structures. The N∩N binding mode is through the azomethine nitrogen and the nitrogen of the thiazole ring, forming a five-membered chelating ring. The synthesized ligands and complexes were then tested for their antibacterial properties against three strains of bacterial microorganisms, Staphylococcus aureus (+ve), Klebsiella pneumoniae (−ve), and Escherichia coli (−ve).

KEYWORDS:

• Ruthenium
• iridium
• hydrazineyl-thiazole
• antibacterial studies

Acknowledgements

The author thanks the Centre for Advanced Studies in Chemistry, NEHU, for the FT-IR analysis and SAIF-NEHU and SAIF-IISc Bangalore for the NMR analysis.

Disclosure statement

No potential conflict of interest was reported by the authors.