SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF INDOLE DERIVATIVE BEARING THE PYRAZOLE MOIETY

Series of 1 of  1-[(3,5 diphenyl substituted ) -4,5-dihydro-1H-pyrazol-1-yl]-2-(3H-indol-3-yl) ethan-1-one (5a-5j)  derivatives were synthesized by the reaction between indole 3 acetic acid hydrazide and various chalcones (3a-3j). The Chalcones were prepared by Claisen-Schmidt condensation reaction in which substituted aromatic aldehydes was treated with simple acetophenone(aromatic ketones) in presence of 20% base(NaOH) and indole 3 acetic acid hydrazide was prepared by reaction between 3 indole acetic acid with hydrazide. The synthesized new compounds were identified by spectral studies and elemental analysis, and were evaluated in vitro for their antimicrobial activity using standard agar diffusion method and using four bacterial strains (Bacillus, Pseudomonas, Escherichia coli and Staphylococcus) and two fungal strains (Sclerotium rolfsii & Macrophomina phaseolina) most of compounds such 5c.5a,5b,5f,5g  i.e 1-[5-(4-Chloro phenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl] – 2 – (3H-indol-3-yl) ethan-1-one (5c), 1-(3, 5-diphenyl-4,5-dihydro-1H-pyrazol-1-yl) -2-(3H-indol-3-yl) ethan-1-one (5a), 1-[5-(4-methoxyphenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl]-2-(3H-indol-3-yl) ethan – 1-one( 5b), 1-[5-(4 dimethyl amino phenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl]-2-(3H-indol-3-yl)ethan-1-one(5e), 1-[5-(4 Hydroxyl 3 Methoxy  phenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl]-2-(3H-indol-3-yl)ethan-1-one(5g). Shows good activity against gram positive and gram negative bacteria. All the compound exhibits moderate to average antifungal activity.