Among a wide variety of heterocycles that have been explored for developing pharmaceutically important molecule, isoxazoline and isothiazoline are one of them. Several nitrogen and sulfur containing heterocycle compounds are useful in pharmaceutical chemistry. All the compounds have been characterized by elemental analysis IR, NMR and Mass spectral data. All the compounds have been screened for their antimicrobial activity to gram positive and gram negative bacterial strains and antifungal activity. The antimicrobial activities of the synthesized compounds have been compared with standard drugs like Amoxicillin, Ciprofloxacin and Griseofulvin.