Synthesis and biological studies of bis (thiadiazole/triazole) by sonication

5,5-Dimethylcyclohexane-1,3-dione was treated with semicarbazide to yield its acid hydrazide, which on further reaction under ultrasound condition with aryl isothiocyanates gave 1,3-bis-imino-[1-(carboxy)-4-substituted phenylthiosemicarbazide]-5,5-dimethylcyclohexane. This compound in acidic medium gave 1,3-bis-imino-[5-(substituted) phenylamino-1,3,4-thiadiazol-2-yl-]-5,5-dimethylcyclohexane, whereas in basic medium 1,3-bis-imino-[4-(substituted) phenyl-5-mercapto-1,2,4-triazol-3-yl-]-5,5-dimethylcyclohexane was obtained. The synthesized compounds were investigated for their antibacterial activities. The results indicated that the compounds show convincing activities against Gram-positive bacteria (S. aureus, C. diphtheriae and S. cerevisiae) when compared with standard drug (ampicillin trihydrate). These compounds were also synthesized by conventional method and their structures have been elucidated on the basis of spectral analyses and chemical reactions.