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1,2,3-Benzotriazine is an important class of organic compounds due to their diverse pharmacological activities . The biological activities as well as the chemistry of 1,2,3-benzotriazine derivatives are reviewed.This investigation describes the synthesis of 1,2,3-benzotriazine derivatives containing hexahydroquinolone moiety Va-m as structural analogues to norfloxacin and ciprofloxacin which are used clinically as antibiotics.The key intermediate 2-(4-oxo(3H)-1,2,3-benzotriazin-3-yl)aceto-hydrazide (II) is prepared via two step reaction .The first involves the reaction of diazotized methyl anthranilate with ethyl glycinate hydrochloride to give compound I . Hydrazinolysis of the later affords compound II.Reaction of compound II with 5,5-dimethyl-1,3-cyclohexanedione (dimedone) yields N’-(5,5-dimethyl-3-oxocyclohex-1-enyl)-2-(4-oxo(3H)-1,2,3-benzotriazin-3-yl) acetohydrazide (III) . Cyclization of compound III with different 3-aryl-2-substitutedacrylonitriles IVa-m gives hexahydroquinolines Va-m . However, the acridinediones VIa-e are synthesized by heating two molar amounts of enaminodimedone III with the appropriate 3-aryl-2-cyano-acrylonitrile in acetic acid containing few drops of TMA.The synthesis of N-(4-oxo(3H)-1,2,3-benzotriazin-3-ylacetyl) hydrazones (VIIa-g) ,starting from the hydrazide (II) and certain carbonyl compounds in ethanol is also investigated.Moreover, this thesis deals with the preparation of 1,2,3-benzotriazine derivatives as new anti-inflammatory agents .The construction of 1,2,3-benzotriazine bearing thiosemicarbazide VIII is achieved through the reaction of compound II with phenyl isothiocyanate. The thiosemicarbazide derivative VIII is converted to the corresponding 1,3,4-thiadiazole IX, 1,3-thiazole X, and 1,3,4-oxadiazole XI, through the reaction with different reagents as concentrated sulphuric acid , phenacyl bromide , dicyclohexylcarbodiimide (DCC) respectively.Moreover , cyclization of compound II with 2,5-hexanedione in acetic acid affords N-(2,5-dimethyl-1H-pyrrol-1-yl)-2-(4-oxo(3H)-1,2,3-benzotriazin-3-yl) acetamide (XII).Besides , condensation of the hydrazide II with acetylacetone and benzoylacetone in ethanol respectively affords 3-[2-(3,5-disubstituted-1H-pyrazol-1-yl)-2-oxoethyl]-4-oxo(3H)-1,2,3-benzotriazines (XIIIa,b) which show promising anti-inflammatory activity.In addition , 2-(4-oxo(3H)-1,2,3-benzotriazin-3-yl)-N-arylacetamides (XVIa-f) are synthesized by heating 1,2,3-benzotriazin-4(3H)-one (7) with 2-chloro-N-arylacetamides XVa-f in dimethylformamide (DMF) containing anhydrous potassium carbonate .Screening for the antimicrobial activity of compounds Va-m is performed against ciprofloxacin as standard. The tested compounds exhibit a significant antimicrobial activity against G+ve bacteria more than the standard , but they are less potent than the standard ciprofloxacin against G-ve bacteria . Neither ciprofloxacin nor the tested compounds exhibit any antifungal activity .The anti-inflammatory activity of seven compounds Va , IX , XII , XIIIa , XIIIb , XVIa and XVId is also inspected . The results reveal that the tested compounds not only possess a marked anti-inflammatory activity but also, less ulcerogenic side effect . Although the tested compounds have lower anti-inflammatory activity than the standard indomethacin , they exhibit less ulcerogenic effect . However they are still more ulcerogenic than the selective Cox-2 inhibitor celecoxib .IntroductionBiological Activities of 1,2,3-Benzotriazine .Literature review indicated that , substituted 1,2,3-Benzotriazines are associated with a wide range of biological activities.1- Anti-inflammatory activity.In 1967 , some of the synthesized 3-substituted-1,2,3-benzotriazin-4(3H)-ones (1) were reported to have (2) effective anti-inflammatory ,antipyretic and analgesic
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