猫爪草的研究I. 7-脱氧马钱子酸及对毛钩藤五环氧化吲哚生物碱的¹⁵N核磁共振光谱研究

Investigation of Uña De Gato I. 7-Deoxyloganic acid and 15N NMR spectroscopic studies on pentacyclic oxindole alkaloids from Uncaria tomentosa.

作者信息

Muhammad I, Dunbar D C, Khan R A, Ganzera M, Khan I A

机构信息

National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677, USA.

出版信息

Phytochemistry. 2001 Jul;57(5):781-5. doi: 10.1016/s0031-9422(01)00043-7.

DOI:10.1016/s0031-9422(01)00043-7

PMID:11397448

Abstract

The C-8-(S) isomer of deoxyloganic acid (7-deoxyloganic acid), together with beta-sitosteryl glucoside, five known stereoisomeric pentacyclic oxindole alkaloids and the tetracyclic oxindole isorhyncophylline, were isolated from the inner bark of Uncaria tomentosa. Structures of the isolated compounds were based on 1H and 13C NMR data, mainly 2D NMR experiments, including 1H-13C HMBC and 1H-1H NOESY correlation. Furthermore, the hitherto unreported 15N chemical shifts of the isomeric oxindole alkaloids, using 1H-15N HMBC experiments, were utilized to facilitate their characterization. Uncarine D showed weak cytotoxic activity against SK-MEL, KB, BT-549 and SK-OV-3 cell lines with IC(50) values between 30 and 40 microg/ml, while uncarine C exhibited weak cytotoxicity only against ovarian carcinoma (IC(50) at 37 microg/ml).

摘要

从毛钩藤的内皮中分离出了脱氧马钱子酸（7-脱氧马钱子酸）的C-8-(S)异构体，以及β-谷甾醇葡萄糖苷、五种已知的立体异构五环氧化吲哚生物碱和四环氧化吲哚异钩藤碱。所分离化合物的结构基于1H和13C NMR数据，主要是二维NMR实验，包括1H-13C HMBC和1H-1H NOESY相关。此外，利用1H-15N HMBC实验测定了异构氧化吲哚生物碱迄今未报道的15N化学位移，以促进其表征。钩藤碱D对SK-MEL、KB、BT-549和SK-OV-3细胞系表现出较弱的细胞毒性活性，IC(50)值在30至40微克/毫升之间，而钩藤碱C仅对卵巢癌表现出较弱的细胞毒性（IC(50)为37微克/毫升）。