Synthesis, Antimicrobial and Anticancer Activities of 5-(4-Substituted-Phenyl)-1,3,4- Thiadiazole-2-Amines

Abstract

A series of 5-(4-substituted phenyl)-1,3,4-thiadiazole-2-amines (4a-h) were prepared from dehydrocyclization of 4-substituted benzoyl thiosemicarbazides (3a-h) using concentrated sulphuric acid. The chemical structures of compounds were elucidated by Infra-red, NMR, Mass spectral and elemental analyses. Antibacterial activities of these compounds against Staphylococcus aureus, Bacillus substilis, Eschereria coli and Pseudomonas aeruginosa using Ciprofloxacin while antifungal activities against Aspergillus niger and Candida albicans using Fluconazole as standard drugs were performed. Minimum inhibitory concentrations and anticancer activity of potent compounds was determined. The results indicate that compounds 4(a), 4(b) and 4(c) possess significant antibacterial activity whereas compounds 4(f) and 4(g) possess significant antifungal activity among the series of synthesized thiadiazoles comparing with standard drugs. Further, the results of anticancer studies on breast cancer cell line suggested that some potent antimicrobials i.e. 4(c), 4(f) and 4(g) associated with moderate to good anticancer activity. Thus, it may be found that synthesized compounds have good antibacterial activity and moderate antifungal activity. However, these compounds could be further screened for the antibacterial activities against a battery of bacteria to achieve their broad spectrum profile and also used to screen cytotoxic effect against other cancer cell lines.