#195 Synthesis, characterization and antifungal activity of azo coupled dihydropyrimidinones

Abstract

DHPM scaffold were reported to exhibit versatile biological activities. These derivatives possess antimicrobial property which reviewed from the literature. These is a very few study carried out on azo coupled dihydropyrimidinones. So the study focused towards the synthesis of azo coupled DHPMs and the synthesized compounds evaluated for antifungal actions against A. flavus. Synthesis of DHPMs from cyclocondensation between dicarbonyl compounds, diamide, aromatic aldehydes in acidic conditions. Diazonium salt of aromatic amine prepared which then coupled with DHPMs. The synthesized compounds checked to know the composition of elements present. Characterization of compounds done by IR, proton NMR and Mass spectral techniques. Evaluation of in-vitro antifungal activity by well diffusion method. Synthesis of 3, 4-dihydropyrimidinones from cyclocondensation multicomponent one pot synthesis from dicarbonyl compound (acetyl acetone), diamide (urea) and aromatic aldehyde in ethanol in presence of concentrated hydrochloric acid under reflux for 4 h. Synthesis of aryl diazonium salt from 4-nitro aniline. Coupling of aryl diazonium salt with dihydropyrimidinone in presence of 10% NaOH solution. Purification of the synthesized azo coupled DHPM compounds using suitable solvent. The synthesized DHPMs compounds were characterized by IR, NMR, Mass spectral analysis. The azo coupled dihydropyrimidinones compounds were tested for antifungal activity against A. flavus. Antifungal actions of tested compounds were indicated by the zone of inhibition. From the test results, it was found to be all the compounds inhibit the growth of A. flavus. The maximum activity produced by the synthesized azo coupled compounds may be due to the presence of electron donating groups present in the DHPM scaffold coupled with azo derivatives of electron withdrawing group. This study investigated with synthesis, characterization and In-vitro anti-fungal evaluation of azo coupled 3, 4-dihydropyrimidine-2-ones derivatives against A. flavus strain. The compound were synthesized by three steps process. DHPMs prepared from one pot multicomponent condensation of acetyl acetone, urea and various substituted aldehydes in ethanol in presence of Concentrated HCl. All synthesized compounds were obtained in moderate yield. The melting point of synthesized compounds were determined in open capillary method. Purity of compounds checked by thin layer chromatography using silica gel Gas stationary phase and hexane and ethyl acetate as mobile phase. All the compounds were obtained in pure state. The synthesized compounds are characterized by IR, ¹H-NMR and Mass spectral analysis for elemental analysis. The synthesized compounds in-vitro antifungal activity was evaluated against the A. flavus. This study concluded that the azo coupled dihydropyrimidinones possess good antifungal activity against A. flavus cause the aspergillosis.