Department of Analytical Chemistry, Faculty of Medicine, Universidad Autónoma de Nuevo Leon, P.O. Box 2316, Sucursal Tecnológico, Monterrey, N.L., 64841 Mexico.
J Nat Prod. 2011 Sep 23;74(9):1842-50. doi: 10.1021/np2000667. Epub 2011 Aug 22.
Bioactivity-guided fractionation of the methanolic root bark extract of Leucophyllum frutescens led to the identification of leubethanol (1), a new serrulatane-type diterpene with activity against both multi-drug-resistant and drug-sensitive strains of virulent Mycobacterium tuberculosis. Leubethanol (1) was identified by 1D/2D NMR data, as a serrulatane closely related to erogorgiane (2), and exhibited anti-TB activity with minimum inhibitory concentrations in the range 6.25-12.50 μg/mL. Stereochemical evidence for 1 was gleaned from 1D and 2D NOE experiments, from 1H NMR full spin analysis, and by comparison of the experimental vibrational circular dichroism (VCD) spectrum to density functional theory calculated VCD spectra of two diastereomers.
生物活性导向分离 Leucophyllum frutescens 的甲醇根皮提取物，得到了 leubethanol（1），这是一种新型的锯齿烷型二萜，对多药耐药和敏感的毒力结核分枝杆菌菌株均有活性。通过 1D/2D NMR 数据鉴定 leubethanol（1）为与 erogorgiane（2）密切相关的锯齿烷，并表现出抗结核活性，最低抑菌浓度范围为 6.25-12.50 μg/mL。通过 1D 和 2D NOE 实验、1H NMR 全自旋分析以及实验振动圆二色性（VCD）谱与两种非对映异构体的密度泛函理论计算 VCD 谱的比较，获得了 1 的立体化学证据。
