PREPARATIONOFSOME2-AMINOISOXAZOLYL- p-QUINONES DERIVATIVES

Abstract

Quinone derivatives are important compounds as they are widely distributed in nature and associated with abroad range of biological activities. Inthis work synthesis ofp-quinone derivativescontiningα,β-unsaturated carbonylor isoxazoleunit was accomplished. Further,intermediate six α,β-unsaturated carbonyl compounds, beside six isoxazole derivatives were prepared.P-aminoacetamidobezene-suphanamido–p-acetophenone was reacted with some aldehydes (benzealdehyde,salicyaldehyde, anisalaldehyde, furfuraldehyde, acetaldehyde, cinnamaldehyde) in basic medium to furnish the corresponding α,β-unsaturated carbonyl derivatives by Clasin–Schemit reaction. The prepared α,β-unsaturated carbonyls weretreated with hydroxylamine hydrochloride giving isoxazolesin a cyclization reaction. Hydrolysis of the acetamidoisoxazole and α,β-unsaturated carbonyl compounds in hydrochloric acid and ethanol yield the corresponding amino derivatives. Quinone derivatives were prepared by the reaction of amino compounds of α,β-unsaturated carbonyls andaminoisoxazoles with different p-quinones (1,4-benzoquinoe, 1,4-naphthaquinone, 2-methyl-1,4-naphthaqunone)in a conjugate addition reaction . The reaction steps and the purity of the products werechecked by using thin layer chromatography (TLC). The chemical structure ofintermediate and final compounds were characterized and confirmed bymeasuring their melting points, FT-IR spectroscopy,UV-Vis and 1H-NMR. The retrosnythetic analysis of the target compounds was discussed in chapter three together with suitable mechanism. The spectral data were discussed in the same chapter. Some of the prepared compounds showed significant activity at the level of 10 µg/µl against some bacteria and fungi.