Instituto de Productos Naturales y Agrobiología, C.S.I.C., Avda. Astrofísico F. Sánchez 3, 38206-La Laguna, Tenerife, Canary Islands, Spain.
Instituto de Productos Naturales y Agrobiología, C.S.I.C., Avda. Astrofísico F. Sánchez 3, 38206-La Laguna, Tenerife, Canary Islands, Spain.
Phytochemistry. 2022 Sep;201:113289. doi: 10.1016/j.phytochem.2022.113289. Epub 2022 Jun 20.
Mono- and di-substituted tricycloalternarenes form a group of meroterpenes isolated from epiphytic fungi. In this work, we have made thirteen proposals to correct erroneous structures of disubstituted tricycloalternarenes, also known as guignardones. Thus, in this group of compounds, structures of guignardones K, L, M, W, tricycloalternarene B, 15-hydroxy-tricycloalternarene 5 b, guignardiaene D, magnardones F-H and coibanols A-C, have been revised. Moreover, we have also explained why there are only two types of disubstituted tricycloalternarenes in nature, one with a -CH-O- β-bridge between C-6 and C-4 (6R,4S-configuration), and the other with a -CH-O- α-bridge between C-4 and C-6 (4R,6S-configuration). Finally, the relative and absolute configurations of phyllostictone A and the absolute structure of phyllostictone D have been established by comparison with those of magnardones I and D, respectively.
单取代和二取代三环倍半萜烯是一类从附生真菌中分离得到的混合萜类化合物。在这项工作中，我们对二取代三环倍半萜烯（也称为 Guignardones）的错误结构提出了十三个修正建议。因此，在这组化合物中，Guignardone K、L、M、W、三环倍半萜烯 B、15-羟基三环倍半萜烯 5b、Guignardiaene D、Magnardones F-H 和 Coibanols A-C 的结构都得到了修正。此外，我们还解释了为什么自然界中只有两种类型的二取代三环倍半萜烯，一种是在 C-6 和 C-4 之间具有-CH-O-β 桥（6R，4S-构型），另一种是在 C-4 和 C-6 之间具有-CH-O-α 桥（4R，6S-构型）。最后，通过与 Magnardones I 和 D 的比较，确定了 Phyllostictone A 的相对和绝对构型以及 Phyllostictone D 的绝对结构。
