Kaumil Navnitbhai Modi, Sanjay D. Panchal and Prof. Dr. Dhrubo Jyoti Sen
2-oxo-4,6-diphenyl-2,6-dihydropyrazolo [1,5-a] [1,3,5] triazine-7- carbonyl ring system has been synthesised by the reaction between phenyl hydrazine and ethyl acetoacetate produced pyrazolone moiety which on benzoylation produced benzoyl derivative which on condensation with urea produced 7-methyl-4,6- diphenylpyrazolo-[1,5-a][1,3,5]triazin-2(6H)-one ring which on alkaline oxidation with KMnO4/KOH produced carboxylic moiety. Treatment with thionyl chloride of produced acid chloride derivative. This on condensation with Mannich base produced by benzaldehyde and p-chloro benzaldehyde with urea/thiourea/guanidine produced the desired moiety. The synthesised compounds were characterised by N% and spectral datas and antimicrobial and antifungal screening has been performed by zone of inhibition studies and MIC calculation with standard antibiotic/antifungal drug against (gram+ve) and (gram– ve) bacteria and fungal strains on agar media after 24 hours incubation at 37°C for antimicrobial activity and 24°C for antifungal activity. Gram positive: Staphylococcus aureus ATCC 9144, Bacillus subtilis ATCC 6633, Gram negative: Escherichia coli ATCC 25922, Fungal strain: Candida albicans ATCC 10231 It has been observed that the Compound-6c (X=NH) showed maximum antibacterial activity against Escherichia coli, Compound-6a (X=O) against Bacillus subtilis and Compound- 6e (X=S) against Staphylococcus aureus. Oxygen and Sulphur has two lone pairs whereas Nitrogen has one lone pair of electrons but the electronegativity of Oxygen (X=O; 3.5), electronegativity of Sulphur (X=S; 2.4) and electronegativity of Nitrogen (X=N+H; 3.1+2.2=5.3). MIC value of all the compounds have been found as 250Hg as Minimum Inhibitory Concentration by serial dilution method and MIC of Ampicillin is 25Hg and for Fluconazole is 5.5Hg. Keywords: Pyrazolo-triazine, Antibacterial, Antifungal, Benzoylation