syntheses, characterization and biological evaluation of some new (2e)-1-(4’-bromophenyl)-3-(4-(diphenylamino)phenyl)prop-2-en-1-one chalcones and their analogues

Eight novel triphenylamine chalcones with different substitution patterns were successfully synthesized using the conventional claisen- schmidt condensation reaction in the basic medium at room temperature, and purified by recrystallization method using ethanol, the percentage yield of the compounds were between 30 – 92 %. the synthesis of the target chalcones involves a nucleophilic enolate attack on the electrophilic carbonyl carbon of 4-(diphenylamino) benzaldehyde resulting in the formation of a new carbon-carbon bond. the triphenylamine chalcones were characterized by means of ft-ir and nmr spectroscopic analyses. the antimicrobial screening against different pathogens revealed that, all synthesized compounds showed marked activity against the tested microbe. (e)-3-(4-(diphenylamino) phenyl)-1-(3'-nitrophenyl) prop-2-en-1-one (1b) showed the highest zone of inhibition against aspergillus niger, measuring 30 mm. the minimum inhibitory concentration (mic) results revealed that, (e)- 1-(4'-bromophenyl)-3-(4-(diphenylamino)phenyl)pr op-2-en-1-one (1a), (e)-3-(4-(diphenylamino)phenyl)-1-(3'-nitrophenyl) prop-2-en-1-one (1b), (e)-1-(4-chlorophenyl)-3-(4-diphenylamino) phenyl)prop-2-en-1- one (1c), (e) -3- (4-diphenylami- no) phenyl)-1-(4'-fluorophenyl) prop-2- en-1-one (1d) and (e)-4-(3-(diphenylamino) phenyl)-1-(4-fluorophenyl)- 2-methylbut-3-en-1-one (2d) had the lowest mic and inhibit the growth of aspergillus niger at 12.5 μg/ml. all the synthesized compounds showed an mbc/mfc effect against escherichia coli, pseudomonas aeruginosa, bacillus subtilis, candida albicans, and aspergillus niger at 50 μg/ml.