الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Synthesis of New Purine Analogues. Coupling of benzene diazonium chloride with sodium salt of 3-hydroxy-1-substituted prop-2-en-1-one 1 afforded the hydrazonoformylketone (3-aryl-3-oxo-2-(phenyl-hydrazono)propanaldehyde) 2a-c. Condensation of compounds 2a-c with 3-aminopyrazole derivatives 3 in the presence of ethanol containing catalytic amount of pipredine or TEA as one step reaction afforded in good yields the solid products-7-aryl-6-phenylazo-2,3-disubstituted-pyrazolo[1,5-a]pyrimidine 7a-x. The structures of compounds 7a-x were confirmed on the basis of elemental analysis and spectroscopic data (IR, MS, 1H-NMR, and 13C-NMR). Similarly, reaction of 3-aryl-3-oxo-2-(phenyl-hydrazono)propanaldehyde 2a-c with hydrazine derivatives in stirring ethanol containing catalytic amounts of triethylamine gave hydrazono pyrazole derivatives 8a-f. The structure of compounds 8a-f were confirmed on the basis of elemental analysis and spectroscopic data (IR, MS, 1H-NMR, and 13C-NMR). Also, 2a-c can be reacted with o-phenylene diamine in stirring ethanol containing catalytic amount of triethylamine to afford the hydrazono derivatives 9 not the diazipine derivatives 10 The structures of compound 9 are the most convenient structure according to the elemental analysis and spectroscopic data. On the other hand, compounds 2a-c were reacted with 2-amino thiazole derivatives 11 to afford the expected thiazoleopyrimidine 13 according to the mechanism of the synthesis of structures 7. But, the elemental analysis and spectroscopic data delivered the structures of compound 12 not 13. Elemental analysis, and spectral data (IR, MS, 1H-NMR, and 13C-NMR) elucidated the structure of the newly compounds. Part II Synthesis of new hydrazonothiazole and hydrazono[1, 3, 4]thiadiazole derivatives. Reaction of (3-aryl-3-oxo-2-(phenyl-hydrazono)propanaldehyd) 2a-c with thiosemicarbazide gave the hydrazonothiosemicarbazide 15 not mercaptotriazole 14 or 2-mercapto-pyrimidine 16. The structures of compounds 15 were confirmed on the basis of elemental analysis and spectroscopic data (IR,1H-NMR and MS). Treatment of compound 15b with hydrazonoyl halides 17 afforded the diazothiazole derivatives 19 not the triazole derivatives 18. The proposed mechanism of the reaction was given as following. Firstly via acylation of the hydrazonothiosemicarbazide 15 by elimination of hydrochloric acid and then cyclized by loses of water molecule to afford thiazole derivatives 19. Secondly via acylation of hydrazonothiosemicarbazide 15 through dehydro-chlorination and then cyclized by loses of H2S molecule to give the triazole derivatives 18. According to the elemental analysis the produced compound contains sulfur atom that fix the first suggestion and the spectroscopic data confirmed the structures of compound 19. Compounds 19 were given via alternative chemical synthesis through the reaction of hydrazonothiosemicarbazide derivatives 15 with a-halo compounds 20 to give the corresponding thiazole derivatives 21, which were subjected to couple with diazonium chlorides to furnish the diazothiazole derivatives 19. The structures of compound 21 were confirmed on the basis of elemental analysis and spectroscopic evidences. Further confirmations of compound 21 were given by coupling with diazonium chlorides to furnish the thiazoles 19. Similar treatment of hydrazonothiosemicarbazide derivatives with hydrazonoyl halides 22 afforded the hydrazonothiazoles-3-one derivatives 23. The structures of compound 23 were confirmed on the basis of elemental analysis and spectroscopic data. The synthetic potential of hydrazonoformylketone 2 was domenstrated via their reaction with carbodithioate 24 to furnish the diazocarbodithioate 25. The structures of compound 25 were elucidated according to elemental analysis and spectroscopic data. Treatment of diazocarbodithioate 25 with hydrazonoyl chloride or nitrilimine 17 or 22 in ethanolic triethylamine solution gave one isolable product according to TLC, upon elemental analysis, and spectroscopic data, the structure of the product was formulated as 1,3,4-thiadiazole derivatives 29 not the triazole derivatives 28. Seems to be the most plausible pathway for the formation of structures 29. The reaction involves initial formation of thiohydrazonate which undergoes intermolecular cyclization as soon as it is formed to yield the intermediate 27 or via 1, 3-dipolar cycloaddition of nitrilimine which was prepared in situ from 17 or 22 with triethylamine. The latter was converted into the final product 29 via elimination of the methyl mercaptan. The structure of compounds 29 was confirmed on the basis of elemental analysis and spectroscopic data (IR, MS, 1H-NMR, and 13C-NMR). Part III Synthesis of new Diazo nicotinonitrile and thienopyridine derivatives. Treatment of hydrazonoformylketone derivatives (3-aryl-3-oxo-2-(phenyl- hydrazono)propanaldehyde) 2a-c, with cyanoacetamides or cyanothioacetamides 30 in stirring ethanol containing catalytic amount of triethylamine gave the condensed 3-nicotinonitrile derivatives 34. Thus, it has been found that two modes of cyclization are feasible, giving a 2-mercapto(oxo)-6-(aryl)-nicotinonitrile 34a-f or 2-mercapto-(oxo)-4-(aryl)-nicotinonitrile isomer 33. The structures of compound 34 were confirmed on the basis of elemental analysis and spectroscopic data (IR, 1H-NMR, 13C-NMR and MS). Treatment of compounds 34a-c with alkyl iodide in methanolic potassium hydroxide yielded the corresponding S-alkylated derivatives 35a-f. Treatment of compounds 35a-f with hydrazine derivatives in ethanol containing catalytic amount of piperidines yielded 3-aminopyrazolo[3,4-b]pyridines (36a-f). Reaction of compounds 34a-c with halo derivatives in stirring ethanol for one hour at room temperature afforded the 3-amino-5-diazotheino[2,3-b]pyridine derivatives 38a-r. Compounds 38a-r were elucidated by using (IR, 1H-NMR and MS) spectra.