Abstract
As an effort to synthesize new heterocyclic compounds, which would be expected to have a pharmacological and biological activities, we report here the reactivity of 1-(2,4-dimethoxyphenyl)-3-aryl-2-propen-1-ones (Ia&b), as Michael acceptors under different conditions, towards different Michael donors namely, pyrazolin-5-one, 2-cyanomethylthiazolidin-4-one, thiobarbituric acid, cyclohexanone, and ethyl cyanoacetate affording the adducts bispyrazolo[5,4-b]-4H-pyranes III, 5-oxopyrazolin-4-yl-propan-1-ones IV, 2-(4-oxothiazolidine-2-yl)-5-oxopentano-carbonitrile XI, 4-oxo-4H-pyranol[2,3-d]tetrahydropyrimidin-2-thiones XVI, cyclohexano[b]-4H-pyran XVII, ethyl-5-oxo-pentanoate XVIII, and 1-aroyl-2-arylcyclopropanes XIX respectively. Fusion of XI with excess ammonium acetate yielded 2-aminopyridine derivative XII and 2-aminotetrahydropyridine derivative XIII. Diazotization of XII by treatment with HNO2 at 0°C produced the diazonium chloride derivative XIV which underwent coupling reaction with phenolic compounds to yield the azo-disperse dyes XV. Alkaline hydrolysis of XVIII afforded the corresponding acid XX which reacted with hydrazines by fusion to yield the diazapinone derivatives XXI. The structures of the products obtained were confirmed by elemental analysis, infrared, 1H-NMR, 13C-NMR, and mass spectra. The biological activity for some synthesized products are screened.
The authors would like to express their appreciation to Prof. Dr. K. P. Zeller, Institute fur Organische Chemie, Tubingen University, Tubingen, Germany for performing some 1H- and 13C-NMR, and mass spectra. Many thanks to Prof. Dr. Zahraa Karam El-Din, Microbiology Department, Faculty of Science, Ain Shams University for achievement of biological activities evaluation of some newly synthesized compounds.