Xie Hang, Shi Qing, Miao Yu-Meng, Sun Xin-Yu, Huang Jin-Chang, Lei Chun, Mu Qing, Li Jing-Ya, Hou Ai-Jun
School of Pharmacy, Fudan University, Shanghai, 201203, People's Republic of China.
Shanghai Frontiers Science Center of Drug Target Identification and Delivery, School of Pharmaceutical Sciences, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China.
Phytochemistry. 2025 Sep;237:114537. doi: 10.1016/j.phytochem.2025.114537. Epub 2025 May 18.
Ten enantiomeric pairs of meroterpenoids were isolated from Rhododendron capitatum Maxim. Among them, (+/-)-capitanoids A-F, (+)-ranhuadujuanine B, (-)-rubiginosin G, and (-)-anthopogochromene B are undescribed compounds. Their structures were fully established by spectroscopic techniques, X-ray crystallographic analyses, modified Mosher's method, and ECD calculation. (+/-)-Capitanoid A are the first pair of meroterpenoids possessing an unusual 6/7/5 heterocyclic system characterized by a 1,2,3,3a, 10,10a-hexahydrobenzo [b]cyclopenta[e][1,4]dioxepine motif. (+/-)-Capitanoid F are a pair of meroterpenoids with a tris-normonoterpene moiety that are discovered from the genus Rhododendron for the first time. (+/-)-Rubiginosin G, (+/-)-anthopogochromene B, and (-)-rhodonoid B showed inhibition in hypoxia-inducible factor-1α (HIF-1α) responsive element (HRE) luciferase assay. Furthermore, (+)-anthopogochromene B and (-)-rhodonoid B exhibited suppressive effects on macrophage-mediated inflammatory response by downregulating the pro-inflammatory factor IL-1β expression level and secretion.
从头花杜鹃中分离出了十对映体类倍半萜。其中，(±)-头花杜鹃素A - F、(+)-髯花杜鹃宁B、(-)-锈红菌素G和(-)-花菖蒲色烯B为未报道过的化合物。通过光谱技术、X射线晶体学分析、改良的莫舍尔方法和电子圆二色光谱计算完全确定了它们的结构。(±)-头花杜鹃素A是第一对具有不寻常的6/7/5杂环体系的类倍半萜，其特征为1,2,3,3a,10,10a - 六氢苯并[b]环戊二烯并[e][1,4]二氧杂环庚烷结构单元。(±)-头花杜鹃素F是一对具有三降单萜部分的类倍半萜，首次从杜鹃属植物中发现。(±)-锈红菌素G、(±)-花菖蒲色烯B和(-)-杜鹃素B在缺氧诱导因子-1α (HIF - 1α)反应元件(HRE)荧光素酶测定中显示出抑制作用。此外，(+)-花菖蒲色烯B和(-)-杜鹃素B通过下调促炎因子IL - 1β的表达水平和分泌，对巨噬细胞介导的炎症反应表现出抑制作用。
