Chemistry of some Quinoline Derivatives With Anticipated Biological Activity

Abstract

It is known that several Quinolines and their derivatives possess different pharmacological activities especially their applications as antimicrobial agents. Nowadays, there is a need to synthesize a new series of quinolines less toxic and more effective against different microorganisms. Therefore, the present thesis deals with the synthesis of some quinoline derivatives including alkyl, ester, hydrazide, hydrazone, thiosemicarbazide, triazole, and other biologically active moieties.

The starting compound 3-acetyl-4- methyl-2-quinolinone [I] was prepared by simple method through tihe fusion of o-amino acetophenone and ethyl acetoacetate in the presence of triethyl amine.

The starting compound [I] underwent alkylation with ethyl chloro acetate yielding ethyl [3-acetyl-4-methyl-2-quinolinone-yl] acetate [2] and ethyl [3-acetyl-4-methyl-2-quinoline-2-yl] acetate [3].

Treatment of the two esters [2], [3] with hydrazine hydrate afforded the [3-acetyl-4-methyl-2-quinolinone-1-yl] acetyl hydrazine [5].

The hydrazide derivatives [4] and [S]were considered as starting materials for the synthesis of some new derivatives.

The hydrazide [4] was condensed with some aldehyde and isatine giving the corresponding hydrazones [6,7,8] and [9] respectively.

Ammonium thiocyanate was reacted with hydrazide [4] in acidified aqueous medium giving thiosemicarbazide derivative [IO].

The thiosemicarbazide derivative [I I] was obtained from the reaction of [4] with phenyl isothiocy:anate, which was cyclized in presence ofNaOH to give the triazolo quinoline derivative [I2].