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Abstract Pyrazole is one of the most important nuclei, since it is incorporated in several drugs used in treatment of different diseases. Different compounds contamg pyrazole nucleus are used as antibacterial, antiviral, anti-inflammatory and antipyretic properties. Therefore, we were interested to synthesize a new series of compounds containing pyrazole, Benzoxazmone and naphthalene sulphonyl nuclei bearing a carbohydrate moiety which might increase its biological activity. Synthesis of4-Oxo-2-phenyl-N-[l-aryliden-2-yl methylene] 4-H-3J benzoxazine-6-sulphonylhydrozone derivatives 4a-c via reaction of 2-phenyl-l,3,4-benzoxazinone 1 with cholrosulphonic acid to give the corresponding acid chloride 2 which under reaction with hydrazine hydrate in ethanol afforded hydrazide 3. Condensation of 3 with thiophen-2-carboxyaldehyde, furan-2-carboxyaldehyde and D-glucose in ethanol with drops of glacial acetic acid as catalyst gives the corresponding hydrazone derivatives 4a-c. Equimolar amounts of 4a,b and malononitrile were heated under reflux in ethanol with catalytic amount of triethylarmne to give two isomers of 5-amino-4-cyano-3-arylpyrazole derivatives 5a,b (Scheme-1). Synthesis of 2-(Benzoylammo)-N-4-[(2-aryliden-2-yl methylene)] aroylhydrazone derivatives 8a-f via reaction of corresponding hydrazide 7 with thiophene-2-carboxyaldehyde, furan-2-carboxyaldehyde and sugar-aldehydes namely; D-glucose, D-xylose, D-galactose and D-arabinose in ethanol in the presence of acetic acid as catalyst. Reaction of 8a-d with equimolar amounts of malononitrile under reflux in ethanol with catalytic amount of triethylamine gave 5-amino-4-cyano-3-arylpyrazol derivatives 9a,b and 5-amino-4-cyano-C-nucleosides 9c,d respectively. (Scheme-2). |