Abstract:

Methyl α-[(4-oxoquinazolin-2-yl)thio]acetate (3) is one of the important heterocyclic compounds. It is used as a precursor to synthesize new derivatives of quinazolin-4-one moiety. The compound (4) was synthesized via a series of steps from anthranilic acid. Firstly, the anthranilic acid was converted to its methyl ester (1) by esterification with methanol under acidic condition. The ester (1) was reacted with chloroacetyl chloride to produce methyl α-chloroacetamido benzoate (2). The chloro compound (2) was converted to the to the target precursor (3) by boiling of the chloro compound (2) with ammonium thiocyanate for 12 h. The compound (3) was used as synthon to synthesize new series of five membered ring heterocyclic derivatives, via its conversion to the corresponding acid hydrazide (4). The acid hydrazide (4) was reacted with carbon disulfide under boiling condition to produce 1,3,4-oxadiazole-5-thione derivative (5). The oxadiazole compound (5) was reacted with alkyl halides to afforded the corresponding alkylthio compounds (6-11), and with aromatic aldehydes to afforded the carbinol derivatives (12-18). The synthesized compounds were identified via the physical and spectral data.

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