Microwave –Assisted Synthesis and Characterization of New Heteroaromatic Aldehyde / Ketone- (β-D-ribofuranosyl) thiosemicarbazones

Abstract

A novel synthesis of eleven hetroaromatic aldehyde / ketone of 2- (2,3,5- Tri-O-benzoyl-β-Dribofuranosyl) thiosemicarbazones derivatives (4) have been synthesized by condensation of 2-( 2,3,5- Tri-O-benzoyl-β-D-ribofuranosyl )thiosemicarbazide( 2) with an heteroaromatic aldehyde or ketone (3) ,and then debenzoylated of the resulting product to produce 2-(β-Dribofuranosyl) thiosemicarbazone (5). The synthesis was carried out in ethanol at reflux temperature either by modified domestic microwave oven irradiation or conventional heating (heating mental). Microwave technique gave improved yield in less reaction time All compounds (5a-k) were elucidated by FTIR , 1H-NMR , and elemental analysis .The antibacterial activity of these compounds were tested in vitro by the disk diffusion assay against Escherichia coli as Gram-negative bacteria and Staphylococcus aureus as Grampositive bacteria. Compounds display remarkable antibacterial activity as compared to amoxicillin.