الفهرس 
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Abstract
PART I UTILITY OF 2- (BENZO[D]THIAZOL-2-YL)-3-ARYLACRYLONITRILES OF HETEROCYCLIC SYNTHESIS Acetonitrile derivatives are convenient precursors, which have been extensively utilized, in heterocyclic synthesis. Thus Microwave enhanced synthesis of 2-(benzo[d] thiazol-2-yl)-3-arylacrylonitriles 3a-iwas carried outunder solvent-free conditions using different substituted arylaldehydes 2.Microwave irradiation synthesis under solvent-free conditions of 2-(benzo[d]thiazol-2-yl)-3-arylacrylonitriles )3a-f.(In the present work, we report results aimed to exploring the synthetic potentialities of this reagent and demonstrate results of our trials to produce in the same way other functionally substituted acrylonitriles.It has been found that a mixture of 3f or 3g and activated nitrile 4was heated in ethanol (3f) or dimethylformamide (3g) containing catalytic amount of triethylamine, the reaction yielded1-amino-3-(2-hydroxynaphthalen-1-yl)-3H-benzo[4,5]thiazolo[3,2-a]pyridine-2,4-dicarbonitrile (8a), 1-amino-3-(pyridin-4-yl)-3H-benzo[4,5]thiazolo[3,2-a]pyridine-2,4-dicarbonitrile (8b),1-amino-2-(benzo[d]thiazol-2-yl)-3-(2-hydroxynaphthalen-1-yl)-3H-benzo[4,5]thiazolo[3,2-a]pyridine-4-carbonitrile (8c)and1-amino-2-(benzo[d]thiazol-2-yl)-3-(pyridin-4-yl)-3H-benzo[4,5]thiazolo[3,2-a]pyridine-4-carbonitrile (8d). On treatment 3f, g with ethyl cyanoacetate, 3f behave different behavior than 3g. For 3f, it reactwith ethyl cyanoacetatevia Michael addition of ethyl cyanoacetate to 3f forming the intermediate9which underwent tautomerization from imine form to enamaine form10. The intermediate 10undergo interamolecular cyclization by nucleophilic addition of NH to cyano group forming imino form 11which is converted to final isolable productethyl1-amino-4-cyano-3-(2-hydroxynaphthalen-1-yl)-3H-benzo[4,5]thiazolo[3,2-a]pyridine-2-carboxylate(12).On the other hand, when 3g reactwith ethyl cyanoacetate in boiling ethanol containing catalytic amount of triethylamine to afford 1-hydroxy-3-(pyridin-4-yl)-3H-benzo[4,5]thiazolo[3,2-a]pyridine-2,4-dicarbonitrile (18) as final product. Furthermore, cyanoacetamide, reacts with 3f in refluxing dimethylformamide containing catalytic amount of triethylamine to yield a 1-amino-4-cyano-3-(2-hydroxynaphthalen-1-yl)-3H-benzo[4,5]thiazolo[3,2-a]pyridine-2-carboxamide (23) product of molecular formula C23H16N4O2S (M+412).The pyrazole ring containing benzothiazole moiety26a,b was synthesized by treatment compound 3f, g with hydrazine hydrate.Compound 3gwas used as key intermediate for synthesis isoxazoline and pyrimidine derivative by reaction 3gwith hydroxylamine hydrochloride and guandine nitrate to give 4-(benzo[d]thiazol-2-yl)-3-(pyridin-4-yl)isoxazol-5-amine (27) and 5-(benzo[d]thiazol-2-yl)-6-(pyridin-4-yl)pyrimidine-2,4-diamine (28). PART II SYNTHESIS OF SOME NOVEL AZO COUMARIN DYES CONTAINING BENZOTHIAZOLE MOIETY. Over the years, azo compounds constitute one of the largest classes of industrially synthesized organic compounds, potent in drug and cosmetics. Compound 3cact as a versatile material for synthesis of new 3-(5-(arylazo)-2-hydroxyphenyl)-2-(benzo[d]thiazol-2-yl)acrylonitrile(29a-h)azodyes.Synthesis of 3-(5-(arylazo)-2-hydroxyphenyl)-2-(benzo[d]thiazol-2-yl)acrylonitrile(29a-h).Boiling compounds 29a-h in absolute ethanol containing catalytic amounts of triethylamine for long time afforded 3-(benzo[d]thiazol-2-yl)-6-arylazo-2H-chromen-2-one (31a-h ) via interamolecuar cyclization to form 2-imino-chromene derivatives 30a-h which gave 31a-h on hydrolysis.Synthesis of 3-(benzo[d]thiazol-2-yl)-6-arylazo-2H-chromen-2-one (31a-h).
The formation of 3-(benzo[d]thiazol-2-yl)-6-arylazo-2H-chromen-2-one (31a-h) was elucidated based on their analytical and spectroscopic data. PART II BIOLOGICAL EVALUATION OF NEW SYNTHIZED COMPOUNDS 1-Antioxidant activity: It can be suggested that all compounds except 7, 12 and 16 exhibit moderate to very strong antioxidant activity. The compounds 3c, 3e, 3h, 26a and 8b gave very strong antioxidant activity. 2-Cytotoxic ScreeningThe In vitro Cytotoxicity IC50 (µmol/L)of the new synthesized compounds were studied using the 5-fluorouracil as reference drug, including MCF-7 (breast) and HePG2 (liver)All compounds showed cytotoxity against MCF-7 (breast) and HePG2 (liver), except compounds 12, 8a.Compounds 26a, 3e showed very strong cytotoxity against MCF-7 (breast)andHePG2 (liver), even compound 26a showed cytoxicity more strong than standard drug 5-FC. In addition, compounds 3h has strong cytotoxity activity against MCF-7 (breast), while 8b has strong cytotoxity activity againstHePG2 (liver). Compounds 3c, 8d and 26b exhibit very strong cytotoxity activity against both MCF-7 and HePG2.