A novel pentacyclic triterpene acid from the stem barks of Combretum fragrans F. Hoffm (Combretaceae)

Abstract

A phytochemical study was carried out on stem bark of Combretum fragrans F. Hoffm., a medicinal plant belonging to the Combretaceae family and used traditionally in the treatment of various ailments. Column chromatography separation on silica gel of the crude methanol extract from stem barks of C. fragrans led to the isolation of a new pentacyclic triterpene acid, with a 3,6-epoxide bridge and trivially named as fragransinic acid (1), along with four known compounds: betulin (2), betulinic acid (3), bellericagenin B (4) and a mixture of β-sitosterol (5) and stigmasterol (6). Structures were elucidated by extensive spectroscopic analyses including 1D and 2D NMR, mass spectrometry as well as by comparison with literature data. The above compounds were isolated for the first time from C. adenogonium. Implications for chemosystematics and traditional medicine were briefly discussed.

Graphical Abstract

Keywords:

• Combretaceae
• Combretum fragrans
• fragransinic acid
• pentacyclic triterpenes

Acknowledgements

The authors thank the Agence Universitaire de la Francophonie (AUF) for the financial support of this study. Thanks are also giving to the bioprofiling platform supported by the European Regional Development Fund and the Walloon Region, Belgium, and the Laboratory of Natural Products and Valorization of the University of Yaounde 1 where the research was conducted.

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

The author(s) reported there is no funding associated with the work featured in this article.