Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506-0055, United States.
State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China.
J Nat Prod. 2020 Jun 26;83(6):2041-2044. doi: 10.1021/acs.jnatprod.0c00306. Epub 2020 Jun 4.
Previously, Lin et al. reported the isolation and structural determination of two triterpenoids, garcinielliptin oxide (GO) and garcinielliptone E (GE). Their unusual structural features, which remained unparalleled in subsequent decades despite the intervening discovery of hundreds of other polycyclic polyprenylated acylphloroglucinols (PPAPs), caused us to question the originally assigned structures, so GO was reisolated from , and its NMR spectra were reacquired. In this Note, we revise the structures of GO and the related GE via NMR analysis, biosynthetic considerations, and chemical conversion. Garcinielliptone T, a new PPAP, was also isolated and characterized. GO exhibited weak inhibitory activity against acetylcholinesterase with an IC value of 20.7 μM.
先前，Lin 等人报道了两种三萜类化合物，garcinielliptin 氧化物（GO）和 garcinielliptone E（GE）的分离和结构确定。尽管在随后的几十年中发现了数百种其他多环多聚异戊二烯基酰基间苯三酚（PPAPs），但它们不寻常的结构特征仍然无与伦比，这促使我们对最初分配的结构产生了质疑，因此从 Garcinia parvifolia 中重新分离出 GO，并重新获得了其 NMR 谱。在本说明中，我们通过 NMR 分析、生物合成考虑和化学转化来修正 GO 和相关 GE 的结构。还分离和表征了一种新的 PPAP，garcinielliptone T。GO 对乙酰胆碱酯酶表现出微弱的抑制活性，IC 值为 20.7 μM。
