Two tetranortriterpenoids with new skeletons, xylomexicanins I and J (1 and 2), were isolated during the investigation of chemical constituents from seeds of the Chinese mangrove, Xylocarpus granatum. Xylomexicanin I (1) is an unprecedented limonoid with bridged B- and C-rings. A biosynthesis pathway for 1 from xylomexicanin F is proposed.

中文翻译：

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Xylomexicanins I和J：来自木果木的带有异常B / C环的柠檬苦素

在研究红树林种子木果种子化学成分的过程中，分离出了两个具有新骨架的四降三萜类化合物，即木糖喜树碱I和J（1和2）。Xylomexicanin I（1）是一种前所未有的柠檬苦素，具有桥连的B环和C环。提出了木糖美西宁F的1的生物合成途径。