Shaanxi Engineering Center of Bioresource Chemistry & Sustainable Utilization, College of Science, Northwest A&F University, Yangling, People's Republic of China.
Chirality. 2012 Aug;24(8):668-74. doi: 10.1002/chir.22068. Epub 2012 May 17.
One new cytochalasan alkaloid, chaetoglobosin V(b) (1), together with two structurally related known compounds, chaetoglobosin V (2) and chaetoglobosin G (3), was isolated from the ethyl acetate extract of a culture of the endophytic fungus Chaetomium globosum, associated with the leaves of Ginkgo biloba tree. The structures of the isolated compounds were elucidated by spectroscopic methods including 1D and 2D NMR and mass spectrometry. The absolute configuration of chaetoglobosin V(b) (1) was established by means of electronic circular dichroism (CD) spectroscopy, on the basis of the comparison between the CD spectrum of (+)-1 with that calculated with time-dependent density functional theory method for a simplified model. The correlation between compounds 1-3 was demonstrated by a biomimetic transformation of chaetoglobosin G (3) under mild conditions in chaetoglobosins V and V(b) (1 and 2). The isolated metabolites were tested against some phytopathogens.
从与银杏叶共生的内生真菌卷毛壳菌的乙酸乙酯提取物中分离到一种新的细胞松弛素生物碱 chaetoglobosin V(b)(1)，以及两种结构相关的已知化合物 chaetoglobosin V(2)和 chaetoglobosin G(3)。通过光谱方法，包括 1D 和 2D NMR 和质谱，阐明了分离化合物的结构。通过电子圆二色性（CD）光谱法，根据 (+)-1 的 CD 光谱与简化模型的时间相关密度泛函理论方法计算的光谱之间的比较，确定了 chaetoglobosin V(b)(1)的绝对构型。通过在温和条件下对 chaetoglobosin G(3)进行生物模拟转化，证明了化合物 1-3 之间的相关性，生成了 chaetoglobosins V 和 V(b)(1 和 2)。对分离得到的代谢产物进行了一些植物病原菌的抑菌活性测试。
