Arylpropynals and two equivalents of phloroglucinol react to produce pentacyclic ketals. In addition, 4-methoxydibromocinnamaldehyde also reacted to form procyanidin A-skeleton.

中文翻译：

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快速组装原花青素A骨架

芳基丙炔和两个当量间苯三酚反应生成五环缩酮。另外，4-甲氧基二溴肉桂醛也反应形成原花青素A-骨架。