Abstract :
In the present work we synthesized some novel Chalcones or ?, ?-unsaturated ketones with an aim to obtain some new potent antibacterial and antioxidant agents. The ?, ?-unsaturated ketones were synthesized by base catalysed Claisen-Schmidt condensation of ketones having ?, ?’ hydrogens with various aldehydes. The new series of ?, ?-unsaturated ketones were synthesized by reacting ?-ethylcyclohexanone with different substituted benzaldehydes. The classes of the synthesized compounds are: ?, ?’-Bis(substitutedarylidene)-?-ethylcyclohexanones [1a-h]. The formation of the compounds [1a-h] is indicated by their UV spectra. The functional groups in the compounds [1a-h] are characterized by their IR spectra. The number and positions of protons in the compounds [1a], [1b], [1c], [1d], [1e], [1g]and[1h] are confirmed by their 1H-NMR spectra. The structures of compounds [3a-h] are confirmed by their Mass spectra. The structures of the compounds [1a-h] are further confirmed by their elemental analysis. All the synthesized compounds were screened for their in vitro antibacterial properties against human pathogenic Gram positive and Gram negative bacteria. Ampicillin was used as the standard. The observations reveal that ?,?’-Bis(5-bromo-2-methoxybenzylidene)- ?-ethylcyclohexanone [1c] exhibits highest activity against Staphylococcus aureus. ?,?’-Bis(m-chlorobenzylidene)- ?-ethylcyclohexanone [1g] has highest activity against Escherichia coli. All the synthesized compounds were also screened for their antioxidant activity usingascorbic acid as the standard by DPPH method.
Keyword :
Chalcones, Antioxidant Activity, ?, ?-Unsaturated Ketones