Preparation, Analysis and Antibacterial Evaluation of Some New 1,3,5-Trisubstituted Pyrazole Derivatives

The goal of this study was to develop, synthesise, and characterise a novel 1,3,5-trisubstituted-2-pyrazoline derivative, as well as test its antibacterial activity. The reaction of chalcone derivatives with succinic hydrazide in the presence of pyridine yielded the 1,3,5-tri-substituted-2-pyrazolines derivatives. The IR, 1HNMR, and mass spectral analyses were used to characterise a total of 20 substances. Antibacterial activity of the compounds was tested on five Gm+Ve bacterial strains (Staphylococcus aureus, S. Faecalis, Bacillus Substilis, P. Vulgaris, and B. Pumilus) and two Gm-Ve bacterial strains (Staphylococcus aureus, S. Faecalis, Bacillus Substilis, P. Vulgaris, and B. Pumilus) and two Gm-Ve i.e. Escherichia Coli, Klebsiella Penumoniae in two different concentration i.e. 50 and 100 µg/ml by Agar-diffusion method using Cup-plate method. Standard antimicrobial drugs were Norfloxacin and Ciprofloxacin. The antibacterial activity of substances against Gm+Ve bacterial strains (Staphylococcus Aureus, Staphylococcus Faecalis, Bacillus Substilis, Pseudomonas Vulgaris, and B. Pumilus) suggested the following order of action: BR-3 >BR-2>BR-1>CL-4>BR-4>CL-3> CL-2>CL-5>CL-6>ME-3>ME-2>ME-4>ME-5>ME-6>ME-7>CL-7>CL-8>CL-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME The chemicals of the BR-1 to BR-4 series have the most action. ME-8, CL-8, CL-7, CL-1, ME-5, ME-6, and ME-1 have light activity, whereas CL-2, CL-5, ME-4, CL-6, ME-3, ME-2, and ME-7 have moderate activity. The compounds BR-3, BR-2, BR-1, CL-4, BR-4, and CL-3 have been shown to have excellent action. The result data of antibacterial activity suggested that Cl, Br, F, and Nitro substitution at third and Fifth position may enhance the antbacterial activity of the compounds but the methyl and methoxy substitution may resulted in reduction of the activity.