From Dragon's Blood, a resin produced by plants of the genus Daemonorops (Palmae), six new A-type flavanoid deoxyproanthocyanidins have been isolated. Their structure and stereochemistry, established by chemical degradation and extensive NMR analysis, is consistent with a mechanism of formation common to other constituents of the resin, which involves oxidation of a 6-methylflavan to a quinonemethide, followed by coupling with another flavan moiety.

中文翻译：

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龙血成分。5. Dracoflavans B1，B2，C1，C2，D1和D2，新的A型脱氧原花色素。

从龙血（Daemonorops（Palmae）属植物产生的树脂）中，分离出了六个新的A型黄酮类脱氧原花色素。通过化学降解和广泛的NMR分析确定的它们的结构和立体化学与该树脂其他成分共有的形成机理一致，该机理涉及将6-甲基黄烷氧化为醌甲基，然后与另一个黄烷部分偶联。