State Key Laboratory of Southwestern Chinese Medicine Resources, Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, PR China.
State Key Laboratory of Phytochemistry and Plant Resources in West China, Yunnan Key Laboratory of Natural Medicinal Chemistry, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, PR China.
Phytochemistry. 2021 Jul;187:112780. doi: 10.1016/j.phytochem.2021.112780. Epub 2021 Apr 27.
Whole plants of Gentianella turkestanorum are commonly used as a traditional Uighur medicine. A phytochemical investigation led to the isolation of eight undescribed gentianellane-type sesterterpenoids (18-epi-nitidasin, gentianelloids D-F, and 18-epi-gentianelloids C-F), one undescribed 11,12-seco-gentianellane (18-epi-alborosin), and three known analogs (nitidasin, gentianelloid C and alborosin) among which gentianelloid C was found for the first time from a natural source. The structures of these compounds were elucidated by extensive spectroscopic analyses (including 1D and 2D NMR, HRMS, IR, and specific rotation) and in the case of 18-epi-gentianelloid C by the single-crystal X-ray diffraction analysis. A putative biosynthetic route for these sesterterpenoids was proposed. The immunosuppressive activity of the isolated compounds was also evaluated by their ability to inhibit the proliferation of T cells and T cell cytokine IFN-γ production. Nitidasin suppressed IFN-γ production with an IC value of 16.50 μM, while gentianelloid F and alborosin inhibited the proliferation of and IFN-γ production in T cells with IC values of 12.40-14.66 μM.
新疆獐牙菜全草被广泛用作维吾尔族传统药物。植物化学研究导致分离出了 8 种未描述的獐牙菜烷型倍半萜（18-表-尼替甙辛、獐牙菜内酯 D-F 和 18-表-獐牙菜内酯 C-F）、1 种未描述的 11,12-裂环獐牙菜烷（18-表-阿尔波罗辛）和 3 种已知类似物（尼替甙辛、獐牙菜内酯 C 和阿尔波罗辛），其中獐牙菜内酯 C 是首次从天然来源中发现的。这些化合物的结构通过广泛的光谱分析（包括 1D 和 2D NMR、高分辨率质谱、IR 和比旋光度）以及 18-表-獐牙菜内酯 C 的单晶 X 射线衍射分析来阐明。提出了这些倍半萜的可能生物合成途径。还通过它们抑制 T 细胞增殖和 T 细胞细胞因子 IFN-γ 产生的能力来评估分离化合物的免疫抑制活性。尼替甙辛对 IFN-γ 的抑制作用的 IC 值为 16.50 μM，而獐牙菜内酯 F 和阿尔波罗辛对 T 细胞的增殖和 IFN-γ 的产生的抑制作用的 IC 值为 12.40-14.66 μM。
