Department of Pharmacognosy , Tohoku Medical and Pharmaceutical University , Aoba-ku, Sendai 981-8558 , Japan.
School of Pharmaceutical Sciences , University of Shizuoka , 52-1, Yada , Suruga-ku , Shizuoka 422-8526 , Japan.
J Nat Prod. 2019 Apr 26;82(4):774-784. doi: 10.1021/acs.jnatprod.8b00670. Epub 2019 Mar 21.
Eight isovaleryllignans (1-4 and 8-11), three isovalerylphenylpropanoids (5-7), three known lignans (12-14), and four known compounds were isolated from an extract of the aerial part of Brachanthemum gobicum. The structures of the isolated compounds were elucidated based on NMR and MS data analyses. The enantiomers of compounds 1-3, 5, 8, and 9 were isolated using chiral-phase HPLC, and the absolute configurations of 1a/1b-3a/3b, 5a/5b, 8a/8b, and 9a/9b were elucidated from their optical rotations and ECD spectra; the other lignans were assumed to be racemic or scalemic by chiral-phase HPLC analyses and optical rotation data. Some of the acylated lignans (racemic mixtures) (1-4, 8, 9, and 12-14) exhibited moderate inhibitory activities against Trypanosoma congolense, the causative agent of nagana disease in animals.
从 Brachanthemum gobicum 的地上部分提取物中分离得到了 8 种异戊酰基木脂素（1-4 和 8-11）、3 种异戊酰基苯丙素（5-7）、3 种已知木脂素（12-14）和 4 种已知化合物。根据 NMR 和 MS 数据分析，鉴定了分离得到的化合物的结构。通过手性相 HPLC 分离得到了化合物 1-3、5、8 和 9 的对映异构体，并根据旋光度和 ECD 光谱确定了 1a/1b-3a/3b、5a/5b、8a/8b 和 9a/9b 的绝对构型；通过手性相 HPLC 分析和旋光度数据推断其他木脂素为外消旋或内消旋。一些酰化木脂素（外消旋混合物）（1-4、8、9 和 12-14）对导致 nagana 病的动物病原体 Trypanosoma congolense 表现出中等抑制活性。
