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Abstract Cyanoacetamide in heterocyclic chemistry: Synthesis of new heterocycles with anticipated biological activity This part describes the utility of 2-cyanoacetamide-N-(2-hydroxy ethyl) (1) in the synthesis of many heterocyclic compounds such as pyridine, imidazole, benzothiazole, chromon and thiazole derivatives. This was achieved through the following reactions: 1. Aminopyridone derivative 2 could be obtained through condensation of 2-cyanoacetamide-N-(2-hydroxyethyl) 1 with benzylidene malononitrile under basic conditions. 2. Compound 2 reacted with thionyl chloride to give the corresponding chloro derivative 3 which could be cyclized by refluxing in dimethylformamide in the presence of anhydrous sodium carbonate to give finally the imidazolo pyridine compound 4. 3. Compound 5 has been obtained via the reaction of ethanolamine and benzothiazole acetyl ethyl ester which then reacted with ethylacetoacetate, in glacial acetic acid as a solvent, in presence of ammonium acetate to produce compound 6. 4. Coumarine derivatives 7a, b were obtained when 1 was allowed to react with an equimolecular amount of salicylaldehyde and/or visnaginaldehyde in boiling ethanol in the presence of triethylamine. 5. Thioglycolic acid reacted with 2-cyanoacetamide-N-(2-hydroxyethyl) 1 in dioxane to give thiazole derivative 8. 6. Similarly, compound 8 was allowed to react with salicylaldehyde to give the Coumarine derivatives 9. 7. Other thiazole derivative 10 could be obtained upon reacting compound 8 with equimolar amounts of benzylidene malononitrile under basic conditions. Summary IV 8. The oxime and hydrazone derivatives 11a, b have been obtained via the reaction of 1 with NaNO2 / HCl or phenyl diazonium chloride respectively. 9. Therefore, several new products 2-11 were prepared and many of these compounds have been biologically examined as antibacterial and antifungal. It was found that some of them showed good results where the more activity was associated with certain specific structural characteristics. The assigned structures of the new products were established by analytical and spectroscopic data, such as IR, 1H-NMR, mass spectra and elemental analyses. Cyanoacetyl urea in heterocyclic Synthesis: New uracils used as antioxidants in synthetic rubber This part describes the synthesis of some new uracil derivatives through one step reaction as follows: 1-Cyano acetyl urea 11, as a precursor, was prepared in a good yield from cheap and available chemicals. 2-Treatment of compound 11 with triethylorthoformate and aryl amine derivatives in dioxane affording the uracil derivatives 13a-d. 3-Samiliraly, compound 15 and 17could also be obtained upon reacting cyromazine 14 and / or 4-aminoantipyrene 16 respectively, with triethylorthoformate in dioxane. 4-When, replacement of the cyano group in compound 11 by benzothiazole has been carried out, the interesting benzothiazole uracil derivatives 13e, f were obtained in an excellent yield. Some of the new synthesized compounds were evaluated as antioxidants in synthetic rubber mixes (styrene butadiene rubber) and this evaluation confirmed by phisco-mechincal properties of vulcanizates and scanning electron microscope. The assigned structures of the new products were established by analytical and spectroscopic data, such as IR, 1H-NMR, mass spectra and elemental analyses. |