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PubMed · 15921435

Quinones from Chirita eburnea.

Xiang-Hai Cai·Xiao-Dong Luo·Jun Zhou·Xiao-Jiang Hao
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Abstract

Five new quinone derivatives, (R)-7-hydroxy-alpha-dunnione (1), (R)-8-hydroxy-alpha-dunnione (2), (R)-7,8-dihydroxy-alpha-dunnione (3), (R)-7-methoxy-6,8-dihydroxy-alpha-dunnione (4), and 1,7-dihydroxy-2-hydroxymethylanthraquinone (5), along with seven known compounds, were isolated from Chirita eburnea. All structures were elucidated by spectroscopic techniques (NMR, MS, UV, and IR). The EtOAc fraction of the EtOH extract and compounds 3 and 4 showed free radical (DPPH) scavenging activity, with IC50 values of 101.7 +/- 5.2 microg/mL, 124.82 +/- 8.4 microM, and 45.72 +/- 3.6 microM, respectively, compared with 86.91 +/-6.8 microM for ascorbate.

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AlgorithmsBiphenyl CompoundsDrugs, Chinese HerbalFree Radical ScavengersMagnoliopsidaMolecular StructureNuclear Magnetic Resonance, BiomolecularPicratesPlants, MedicinalQuinonesStereoisomerismJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

Xiang-Hai Cai, Xiao-Dong Luo, Jun Zhou, Xiao-Jiang Hao. 2005. Quinones from Chirita eburnea.. https://doi.org/10.1021/np049632f

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