The utility of 4-isothiocyanato phenylsulfaonamide in the synthesis of some novel thiosemicarbazide, 1,3,4-thiadiazole, pyrazole, pyrazolo[3,4-b]pyridine, 2-oxopyridine and chromene derivatives is reported. All these compounds were characterized by infrared spectroscopy, 1H NMR, mass spectra and elemental analysis. These compounds were screened for their antimicrobial activity.