Antimicrobial activities of heterocycles derived from thienylchalcones

Thiophene analogues of chalcones were synthesized in good yields by condensation of 2-acetylthiophene and salicylaldehydes. Solvent-free Michael addition of cyclohexanone to 2-thienylchalcones devoid of hydroxyl groups yielded 1,5-diketones. The chalcones and 1,5-diketones were utilised as synthons for flavans, 6H-benzo[c]chromen-6-ones, tetrahydro-2H-chromens, tetrahydroquinolines and diazepines. The methods utilised were short and efficient in good yields and operational simplicity. The synthesized heterocyclic compounds were characterised by IR, NMR and HR-MS spectral data and screened for their antimicrobial activity against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Candida albicans. The compounds demonstrated moderate to good antibacterial and antifungal activities. The synthesis of new heterocyclic compounds with an antimicrobial activity argument this study.