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Updated: Mar 23, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Two new ortho benzoquinones from Uncaria rhynchophylla
Qian Zhang1, Lei Chen1, Le-Jian Hu1
1Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China.
Abstract:
The present study was designed to determine the chemical constituents of the stems and hooks of Uncaria rhynchophylla. The chemical constituents were isolated and purified from CH2Cl2 fraction by chromatography. Their structures were elucidated by spectroscopic analyses. Their cytotoxicity was tested using MTT method. Two new ortho benzoquinones, 3-diethylamino-5-methoxy-1, 2-benzoquinone (1) and 3-ethylamino-5-methoxy-1, 2-benzoquinone (2), together with a known compound isorhynchophyllic acid (3) were isolated from U. rhynchophylla. These compounds were evaluated for their cytotoxicity against cancer cells A549, HepG2 and A2780. Compounds 1 and 2 were new ortho benzoquinones and showed weak antiproliferative activities on A549, HepG2 and A2780 cells. Compound 3 significantly inhibited the proliferation of A549, HepG2 and A2780 cells with IC50 values being 5.8, 12.8 and 11.8 µmol·L(-1), respectively.
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