The synthesis of novel chalcone derivatives from N-(4-acetylphenyl)-3-nitrobenzamide, their structural characterization and the investigation of antibacterial activity

Chalcones are 1,3-diphenyl-2-propene-1-one, in which two aromatic rings are linked by a three carbon alpha,beta-unsaturated carbonyl system. Chalcone derivatives are considered to be precursors of flavonoids and isoflavonoids. Chalcones possess conjugated double bonds and a completely delocalized pi-electron system on both benzene rings. Chalcones are synthesized by Claisen-Schmidt condensation of aldehyde and ketone by base catalyzed or acid catalyzed followed by dehydration. In the result of literature studies, it is known that the chalcones show a wide range of pharmacological properties including antibacterial, anticancer, antifungal, antiinflammatory, antitubercular, antitrombosit, antimalarial, antiparasitic, antidiabetic, antileishmanial, antiplatelet activities.In the our present study, it was thought that new chalcone derivatives which was formed linking with the amide group, will be show better antibacterial activity. In this study, N-(4-acetylphenyl)-3-nitrobenzamide [I] which were reacted with 4-aminoacetophenone and 3-nitrobenzoil chloride, was and then this compound were treated with suitable substitue aldehydes in order to obtain new N-(4-{3-[4-substituephenyl]prop-2-enoyl}phenyl)-3-nitrobenzamide [II-XIII] derivatives. All compounds were further evaulated for antibacterial activity against Gram-negative (Pseudomonas aeruginosa, Escherichia coli) ve Gram-positive (Enterococcus faecalis, Staphylococcus aureus) with microdilution process.All reactions was monitored by Thin Layer Chomatography (TLC). The structures of synthesized compounds were identified by UV, IR, 1H NMR, 13C NMR, 1D NMR techniques (DEPT 45, DEPT 90, DEPT 135, APT), 2D NMR techniques (HETCOR, HMBC, COSY) and elemental analysis (C, H, N, S).