Liu Xinqiao, Du Yan, Xie Wenli, Li Xueni, Xu Jing, Chen Yu, Mei Zhinan, Yang Guangzhong
School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan, 430074, PR China.
College of Chemistry and Material Sciences, South-Central Minzu University, Wuhan, 430074, PR China.
Phytochemistry. 2023 May;209:113619. doi: 10.1016/j.phytochem.2023.113619. Epub 2023 Feb 23.
Six scalemic mixtures of previously undescribed diacetylenic spiroacetal enol ethers (DSEEs) and six scalemic mixtures of known DSEEs were isolated from the flowers of Tanacetum tatsienense. Except for E-epidendranthemenol, Z-O-acetyl-epi dendranthemenol, and Z-O-isovaleryl-epidendranthemenol, the remaining scalemic mixtures of DSEEs were resolved by chiral HPLC, and their structures were determined through an analysis of HR-ESI-MS and NMR data. The absolute configurations of seven pairs of enantiomers and one pair of epimers were determined by comparing the experimental and calculated electronic circular dichroism (ECD) spectra. In addition, the inhibitory effects of all of the DSEEs on nitric oxide (NO) production were evaluated in LPS-stimulated RAW264.7 cells. The results showed that (+)-tatsienenol B had a weak inhibitory effect on NO production. The IC value of the compound was 19.78 ± 0.78 μM. This study is the first to report that DSEEs are isolable from plants as scalemic mixtures. Moreover, this study is the first to determine the absolute configurations of DSEEs by chiral resolution and ECD calculations.
从川西菊的花中分离出六种前所未有的二乙炔基螺缩醛烯醇醚（DSEEs）的外消旋混合物和六种已知DSEEs的外消旋混合物。除E-表脱杉醇、Z-O-乙酰基-表脱杉醇和Z-O-异戊酰基-表脱杉醇外，其余DSEEs的外消旋混合物通过手性高效液相色谱法拆分，并通过高分辨电喷雾电离质谱（HR-ESI-MS）和核磁共振（NMR）数据分析确定其结构。通过比较实验和计算的电子圆二色光谱（ECD）确定了七对对映体和一对差向异构体的绝对构型。此外，在脂多糖（LPS）刺激的RAW264.7细胞中评估了所有DSEEs对一氧化氮（NO）产生的抑制作用。结果表明，（+）-川西烯醇B对NO产生有微弱的抑制作用。该化合物的半数抑制浓度（IC）值为19.78±0.78μM。本研究首次报道DSEEs可作为外消旋混合物从植物中分离出来。此外，本研究首次通过手性拆分和ECD计算确定了DSEEs的绝对构型。
