Triterpenoid saponin from the bark of Guaiacum Officinale L.

Abstract

A new triterpenoid saponin, guaianin R (1) was isolated from the n-BuOH extract of bark of Guaiacum officinale L. It was characterized as akebonic acid-3-O-[α-l-rhamnopyranosyl-(1 → 3)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranoside]-28-O-[β-d-glucopyranosyl]-ester. The structure was established with the help of a comparative study of 1D and 2D ¹H-¹³C NMR methods. A number of other saponins were isolated and reported from the same species.

Keywords:

• Guaianin R
• Triterpenoid bidesmosidic saponin
• Bark
• Guaiacum officinale L.
• Zygophyllaceae