الفهرس 
A- Chemistry of coumarinyl chalconesOnly 14 pages are availabe for public view
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Abstract
A novel series of fused and pyrazole-based heterocyclic systems like chromenopyran, chromenodiazepine, diazepine, chromenopyrimidine, triazepinethione, benzodiazepine, and pyrimidopyrimidine derivatives, was prepared from the chalcone derivative namely, 3-(3-(1,3-diphenyl-1H-pyrazol-4-yl)acryloyl)-2H-chromen-2-one (cf. Schemes 1-4).
Treating the chalcone 3 with malononitrile in boiling ethanol and piperidine failed to produce 2-amino-3-cyanopyran derivative 4 and afforded the arylidene malononitrile 5 as a sole product which was identical in all respects with an authentic sample prepared from condensation of pyrazole aldehyde 2 with malononitrile at an ambient temperature. In turn, the pyranochromene derivative 6 was obtained upon cyclocondensation of compound 5 with 4-hydroxycoumarin in boiling ethanol and triethylamine. It was worthy that, cyclocondensation reaction of compound 5 with thiourea in boiling ethanol including anhydrous potassium carbonate led to the formation of 6-aminopyrimidin-5-carbonitrile derivative 7 (Scheme 1).
When chalcone 3 was treated with hydrazine in boiling dioxane, chromenodiazepine derivative 9 was obtained instead of 3-coumarinyl-5-pyrazolylpyrazole derivative 8, Derivative 10 was obtained when chalcone 3 refluxed with hydrazine hydrate in glacial acetic acid (Scheme 2). The reaction of chalcone 3 with thiourea was not successful in boiling dioxane while in boiling sodium ethoxide acquired the chromenopyrimidine derivative 12 instead of pyrimidinethione derivative 11 (Scheme 3).
Interaction of chalcone 3 with thiosemicarbazide in boiling dioxane failed to furnish the pyrazole derivative 13 and afforded the triazepinethione derivative 14. In a similar manner, 2-aminoaniline reacted with chalcone 3 in boiling dioxane to provide benzodiazepine derivative 15. In contrast, pyridopyrimidine derivative 17 was obtained instead of pyridopyrimidine derivative 16 upon treating chalcone 3 with 6-aminothiouracil in boiling dioxane including piperidine (Scheme 4). All synthesized compounds were characterized by using IR, 1H NMR, and the mass spectra. DFT study was investigated for the synthesized compounds.