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Updated: May 11, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
A novel multi-component reaction to imidazo[4,5-g]-quinazolines
Li Li1, Qianqian Zhang, Bo Liu
1Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China. annaleelin@imm.ac.cn
Abstract:
The trace impurities discovered after extended storage of a 5-amino- benzimidazole library were determined as imidazo[4,5-g]quinazoline derivatives by extensive spectroscopic data analysis. The formation of this highly aromatic heterocyclic ring involved a novel multi-component reaction, using which several novel compounds were prepared. Its mechanism was deduced as a cascade of chemical transformations, including the formation of a Schiff's base, intramolecular hetero-Diels-Alder reaction, defluorination and dehydrogenation.
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