Biotransformation of β-Mangostin by an Endophytic Fungus of Garcinia mangostana to Furnish Xanthenes with an Unprecedented Heterocyclic Skeleton
Biotransformation of β-Mangostin by an Endophytic Fungus of Garcinia mangostana to Furnish Xanthenes with an Unprecedented Heterocyclic Skeleton
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DOI：
10.1021/acs.jnatprod.8b00519
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发表时间：
2018-10-01
影响因子：
5.1
通讯作者：
Andersen, Raymond J.
中科院分区：
文献类型：
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作者：
Arunrattiyakorn, Panarat;Kuno, Mayuso;Andersen, Raymond J.
内生真菌菲氏炭角菌（Xylaria feijeensis GM 06）对β-倒捻子素（1）进行生物转化，得到了具有六环杂环骨架的六环稠合氧杂蒽。将β-芒果苷（1）转化为两种非对映异构体对，芒果苷A [（1）-2a/（+）-2 B）]和芒果苷B [（-）-3a/（+）-3 B）]。通过NMR和MS分析确定了转化产物的化学结构，并通过单晶X射线衍射分析确定了芒果苷A的结构为[（-）-2a/（+）-2b）]。以2a和2b的ECD谱为模型，根据计算和测量的ECD数据，确定了3a和3b的绝对构型。本文所述的真菌生物转化提供了将丰富的非手性植物天然产物支架转化为新的手性杂环支架的有效方法，所述新的手性杂环支架代表用于生物活性筛选的扩大的化学多样性。
Biotransformation of beta-mangostin (1) by the endophytic fungus Xylaria feejeensis GM06 afforded hexacyclic ring-fused xanthenes with an unprecedented hexacyclic heterocylic skeleton. beta-Mangostin (1) was transformed to two diastereomeric pairs of enantiomers, mangostafeejin A [(1)-2a/(+)-2b)] and mangostafeejin B [(-)-3a/(+)-3b)]. The chemical structures of the transformation products were' elucidated by analysis of NMR and MS data, and the structure of mangostafeejin A [(-)-2a/(+)-2b)] was confirmed by single-crystal X-ray diffraction analysis. The absolute configurations of 3a and 3b were established on the basis of calculated and measured ECD data using the ECD spectra of 2a and 2b as models. The fungal biotransformation described herein provides an effective method to convert an abundant achiral plant natural product scaffold into new chiral heterocyclic scaffolds representing expanded chemical diversity for biological activity screening.