ABSTRACT
Aryl / alkyl ketones 1 a-c and 5 a-b were condensed with ethylcyanoacetate or malanonitrile afforded 3 a-c and 7 a-b respectively. Treatment on 3 a-c and 7 a-b with sodium azide and ammonium chloride in presence of dimethylformamide yielded 4 a-c and 8 a-b respectively. All the synthesized compounds have been characterized by the IR, NMR and Mass spectrum spectral data. Compounds 4 a-c and 8 a-b were evaluated for antibacterial activity.
ABSTRACT
3-Thiocyanato-7-hydroxy-2-aryl-4H-chromen-4-one 5 a-e have been synthesized from 1- (2,4-dihydroxyphenyl)-2-chloroethanone 1; this reacted with thiocyanate anion afforded 1-(2,4– dihydroxyphenyl)–2-thiocyanatoethanone 2. Reaction of 2 with substituted benzoyl chlorides under modified Baker-Venkataraman conditions directly afforded the diketones 3 a-g, which on cyclization furnished 4 a-g, saponification of which afforded 3-thiocyanato-7-hydroxy-2-aryl-4H-chromen-4-one 5 ag. All of the synthesized compounds have been established by elemental analysis, IR and NMR spectral data. Compounds 5 a-g was screened for antibacterial activity.