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An international journal for chemical science
RESEARCH ARTICLE

Antimicrobial Properties of Mono- and Di-fac-rhenium Tricarbonyl 2-Pyridyl-1,2,3-triazole Complexes

Sreedhar V. Kumar A B , Warrick K. C. Lo A , Heather J. L. Brooks B , Lyall R. Hanton A and James D. Crowley A C
+ Author Affiliations
- Author Affiliations

A Department of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand.

B Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.

C Corresponding author. Email: jcrowley@chemistry.otago.ac.nz

Australian Journal of Chemistry 69(5) 489-498 https://doi.org/10.1071/CH15433
Submitted: 18 July 2015  Accepted: 25 August 2015   Published: 9 October 2015

Abstract

A family of mono- and di-fac-rhenium tricarbonyl 2-pyridyl-1,2,3-triazole complexes with different aliphatic and aromatic substituents was synthesized in good-to-excellent yields (46–99 %). The complexes were characterized by 1H and 13C NMR spectroscopy, infrared spectroscopy, electronic (UV-visible) spectroscopy, high-resolution electrospray mass spectrometry, and elemental analyses. In four examples, the solid-state structures of the rhenium(i) complexes were confirmed by X-ray crystallography. The family of the mono- and di-rhenium(i) complexes and the corresponding 2-pyridyl-1,2,3-triazole was tested for antimicrobial activity in vitro against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) microorganisms. Agar-based disk diffusion assays indicated that most of the rhenium(i) complexes were active against Staphylococcus aureus and that the cationic rhenium(i) complexes were more active than the related neutral systems. However, in all cases, the minimum inhibitory concentrations for all the complexes were modest (i.e. 16–1024 µg mL–1).


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