Newly synthesized triazole-based Schiff base ligands and their Co(II) complexes as antimicrobial and anticancer agents: Chemical synthesis, structure and biological investigations

Abstract The new Schiff base ligands 4-(2′/3′/4′-nitrobenzelideneimino)-3-methyl/ethyl-5-mercapto-1,2,4-triazole and their Co(II) metal complexes were synthesized and characterized by elemental analysis, magnetic moment measurements, thermal studies, electronic absorption and NMR spectroscopy. The ligands were synthesized by condensation of 4-amino-5-mercapto-3-methyl/ethyl-1,2,4-triazole with 2/3/4-nitrobenzaldehyde. On the basis of electronic absorption spectral data and magnetic susceptibility measurements, the octahedral geometry has been proposed for all the Co(II) complexes. Further, the ligands and Co(II) complexes have been screened for their antimicrobial activities against bacteria (Staphylococcus aureus, Pseudomonas aeruginosa) and fungi (Aspergillus niger and Candida albicans). Furthermore, the synthesized compounds were also screened for anticancer activity on human cancer cell lines such as breast (MCF7), lung (NCI-H226), prostate (PC-3) and ovary (OVCAR-3) by sulforhodamine-B (SRB) colorimetric assay.