Novel Four-Step Synthesis of Thioxo-quinazolino[3,4-a]quinazolinone Derivatives

Abstract

A novel synthesis of thioxo-quinazolino[3,4-a]quinazolinone framework was developed through a four-step reaction starting from isatoic anhydride. The resulting 2-aminobenzamides from the reaction of isatoic anhydride and different amines underwent coupling–cyclization reaction with 2-nitrobenzaldehydes, reduction of nitro group, and then cyclization reaction with carbon disulfide (CS₂). All steps were carried out under easy and user-friendly conditions in a short time without using expensive catalysts or reagents.

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GRAPHICAL ABSTRACT

Keywords:

• Carbon disulfide (CS₂)
• heterocycles
• 2-nitrobenzaldehydes
• thioxo-quinazolino[3,4-a]quinazolinone

ACKNOWLEDGMENTS

This research was supported by grants from the research council of Tehran University of Medical Sciences, Iran National Science Foundation (INSF), and Iran National Elite Foundation (INEF).

Notes

^a Isolated yields.