用 1D DOSY 作为溶剂信号抑制工具对一个馏分中的三种甾体皂苷进行表征。Agabrittonosides E-F. 来自龙舌兰属植物的呋甾烷型皂苷。Brachypus.

Characterization of three saponins from a fraction using 1D DOSY as a solvent signal suppression tool. Agabrittonosides E-F. Furostane saponins from Agave brittoniana Trel. spp. Brachypus.

机构信息

Grupo de Alelopatía, Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Cádiz, C/República Saharaui, s/n, 11510 Puerto Real, Cádiz, Spain.

出版信息

Magn Reson Chem. 2010 May;48(5):350-5. doi: 10.1002/mrc.2590.

DOI:10.1002/mrc.2590

PMID:20391439

Abstract

A careful NMR analysis, especially by 1D TOCSY and 1D ROESY, of a refined saponin fraction allowed us to determine the structure of three saponins from a polar extract of Agave brittoniana Trel. spp. Brachypus leaves. The use of 1D DOSY for the suppression of the solvent signal was useful to obtain the chemical shifts of anomeric signals. A full assignment of the (1)H and (13)C spectral data for the new saponins, agabrittonosides E-F (1-2) and the well-known Karatavioside C (3) and their methoxyl derivatives, is reported. The structures were established using a combination of 1D and 2D ((1)H, (1)H-COSY, TOCSY, ROESY, g-HSQC, g-HMBC and g-HSQC-TOCSY) NMR techniques and ESI-MS. In addition, the methoxylation of these furostane saponins in the presence of MeOH was studied.

摘要

通过对精制皂素部分进行仔细的 NMR 分析，特别是一维 TOCSY 和一维 ROESY 分析，我们确定了 Agave brittoniana Trel. spp. Brachypus 叶中极性提取物中三种皂素的结构。使用一维 DOSY 抑制溶剂信号有助于获得端基信号的化学位移。报道了新皂素 agabrittonosides E-F（1-2）和著名的 Karatavioside C（3）及其甲氧基衍生物的（1）H 和（13）C 光谱数据的全归属。结构的确定采用了一维和二维（1）H、（1）H-COSY、TOCSY、ROESY、g-HSQC、g-HMBC 和 g-HSQC-TOCSY）NMR 技术和 ESI-MS 的组合。此外，还研究了这些呋甾烷皂素在甲醇存在下的甲氧基化。