Synthesis and antimicrobial activities of some novel thieno [2,3-d]- Pyrimidin-4(3H)-One derivatives

Pain and inflammation are simultaneous responses in bacterial infections. In current clinical practice, the agents like antimicrobial drug are prescribed concurrently. A POCl3 catalyzed, efficient, one-step and solvent-free synthesis of novel thieno [2, 3-d] pyrimidin-4(3H)-one derivatives from 2-amino-4,5-substitutedthiophene-3-carbonitrile has been developed using various aliphatic acid under conventional heating and microwave irradiation. The formation of compounds was confirmed using elemental analysis and spectroscopic techniques like FTIR, 1H NMR and Mass spectroscopy. All synthesized compounds have been screened for their antimicrobial activity against Escherichia coli (Gram –ve strain), Bacillus subtilis (Gram +ve strain) for antibacterial activity and antifungal activities against Aspergillus niger and Candida albicans. The result showed that synthesized compounds exhibit weak, moderate and good antimicrobial activity. It was observed that the compounds 2a, 2c, 2d, 2e, 2f, 2g, 2j and 2k showed good antimicrobial activity whereas compounds 2b, 2i, 2j showed significant antimicrobial activity compared with standard drug Streptomycin and Amphotericin B respectively. Keyword:POCl3, Thieno[2, 3-d]pyrimidin-4 (3H)-one, Antimicrobial activity, Streptomycin and Amphotericin B