Synthesis and antimicrobial activity of some tetramethylenethieno[2,3-d]pyrimidine derivatives

A series of tetramethylenethieno[2,3-d]pyrimidine derivatives has been synthesized and tested for its antimicrobial properties. All the synthesized compounds were found to exhibit in vitro antibacterial and/or antifungal activity. The highest activity was elicited by 4-benzolhydrazino-5,6-tetramethylenethieno[2,3-d]pyrimidine (9) showing MIC value of 7.81 micrograms/ml against E. Coli and C. albicans, while its MBC value was half that of nystatin. Compound 16 was almost as potent as nystatin exhibiting a minimum bactericidal concentration (MBC) value of 15.62 micrograms/ml.