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Updated: Jul 13, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Synthesis, X-ray structure, and pharmacological activity of some 6,6-disubstituted chromeno[4,3-b]- and chromeno-
Mohamed I Hegab1, Abdel-Samee M Abdel-Fattah, Nabil M Yousef
1Department of Chemistry, Cairo University, Cairo, Egypt. mihegab65@yahoo.com
Abstract:
Some chromeno[4,3-b]quinolines 4a-i were obtained from beta-chloro carboxyaldehydes 3a-c with different aniline derivatives namely, aniline, 4-fluoroaniline, and 2-aminophenol. Surprisingly, 3a-c reacted with 2-aminothiophenol and afforded the chromeno[3,4-c]quinoline derivatives 5a-c. Single-crystal X-ray diffraction studies of 4e and 5b provided good support for the established structure. Compounds 4b and 5b showed significant anti-inflammatory and ulcerogenic score activities compared to that of indomethacin.
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