Characterization of the fraction components using 1D TOCSY and 1D ROESY experiments. Four new spirostane saponins from Agave brittoniana Trel. spp. Brachypus

✍ Scribed by Francisco A. Macías; José O. Guerra; Ana M. Simonet; Clara M. Nogueiras

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 166 KB
• Volume: 45
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.2012

✦ Synopsis

Abstract

A careful NMR analysis, especially 1D TOCSY and 1D ROESY, of two refined saponin fractions allowed us to determine the structures of four new saponins from a polar extract of the Agave brittoniana Trel. spp. Brachypus leaves. A full assignment of the ^1^H and ^13^C spectral data for these new saponins, agabrittonosides A–D (1–4), and one previously known saponin, karatavioside A (5) is reported. Their 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. Moreover, the work represents a new approach to structural elucidation of saponins in refined fractions by NMR investigations. Copyright © 2007 John Wiley & Sons, Ltd.