Synthesis and antimicrobial activity of some 1,3,5-tri substituted pyrazolines

Synthesis and antimicrobial activity of a number of chalcones, 1Hpyrazolines and N-phenyl pyrazolines are described.Anumber of Chalcones (2a-i) were prepared by condensing N-(3-acetylphenyl)-2,3-dichlorobenzamide (1) with different aromatic aldehydes in ethanolic NaOH solution. Cycloaddition of these chalcones (2a-i) was carried out with hydrazine hydrate and phenyl hydrazine furnished 1H-pyrazolines (3a-i), and Nphenyl Pyrazolines (4a-i) respectively. All newly synthesized compounds were characterized by elemental analysis, IR, 1H-NMR, and Mass spectral studies, purity of each compound were checked by TLC using precoated silica gel plate. The synthesized compounds have been screened for their antimicrobial activities against various gram positive and gram negative bacteria and fungi. MIC of each compound was determined.