(E)-3-(4-Oxo-4H-quinazolin-3-yl)-2-propenoic acids, a new series of antiallergy agents
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Updated: Oct 7, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Abstract:
A series of substituted (E)-3-(4-oxo-4H-quinazolin-3-yl)-2-propenoic acids was prepared and evaluated in the rat passive cutaneous anaphylaxis (PCA) test for antiallergic activity. Alkoxy, alkylthio, and isopropyl substituents at the 6- or 8-positions provided highly potent compounds. Conversion to the Z isomer, reduction of the side chain double bond, or reduction of the quinazoline ring resulted in substantial loss of activity. Among the analogues that exhibited oral activity in the PCA test, (E)-3-[6-(methylthio)-4-oxo-4H-quinazolin-3-yl]-2-propenoic acid (5i) was the most potent.
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