Newly Isoxazole derivatives were prepared by reaction of chalcones with hydroxylamine hydrochloride in presence of pyridine and newly Benzodizepine derivatives were prepared by reaction of chalcone with o-phenylenediamine in presence of pyridine. First Chalcones were prepared by treatment of 4-acetyl-5-methyl-2-(4-methylphenyl)-2,4- dihydro-3H-pyrazol-3-one with different Substituted aldehyde by claisen-schimidt condensation. The structures of the newly synthesized Isoxazole and Benzodiazepine derivatives have characterized by IR, 1H-NMR, Mass spectroscopy and elemental analysis. The synthesized compounds were evaluated for their antimicrobial activities