SYNTHESIS OF SOME SELECTED KNOEVENAGEL CONDENSATION COMPOUNDS USING AMBERLITE IRC 86: CHARACTERIZATION AND ANTIMICROBIAL ACTIVITIES

Abstract

Six arylidine derivatives of malononitrile and meldrum's acid namely, 5-(4- (dimethylamino)benzaylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (X1), 2-(4-(dimethylamino) benzylidene) malononitrile (X2), 5-((furan-2-yl)methylene)-2,2-dimethyl-1,3-dioxane-4,6-dione (Y1), 2-((furan-2-yl)methylene)malononitrile (Y2), 5-benzylidene-2,2-dimethyl-1,3-dioxane-4,6- dione (Z1) and 2- benzylidene malononitrile (Z2), were synthesized by knovegagel condensation using piperazine supported Amberlite IRC 86 catalyst. The reaction was clean with shorter reaction time, mild reaction condition, simple workup procedure, eco-friendly and good yields. Structures of the synthesized compounds were proposed by different spectroscopic techniques such as 1H NMR 13C NMR and ESI-MS. All the compounds were assayed in vitro by paper disc diffusion method for their antimicrobial activities against Gram positive (Staphilococus aureous) and Gram negative (Escherichia coli) bacteria and Aspergillus niger and Fusarium fungi. Most of them were found to exhibit promising activity towards the tested microorganisms, when compared to standard drugs.