New acylated triterpenoid saponins from the roots of Acacia polyacantha Willd. (Fabaceae). (January 2023)

• Record Type: Journal Article
• Authors: Atangana, Jean Faustin; Messi, Lin Marcellin; Haddad, Mohamed; Mbing, Joséphine Ngo; Boyogueno Begoude, Aime-Didier; Pegnyemb, Dieudonné Emmanuel; Choudhary, Muhammad Iqbal; Noté, Olivier Placide
• Is Part Of: Carbohydrate research. Volume 523(2023)
• Publication Date: 2023-01
• Subjects: Fabaceae -- Acacia polyacantha -- Acylated triterpenoid saponins -- Polyacosides -- NMR; Carbohydrates -- Periodicals; Chemistry, Organic -- Periodicals; Biochemistry -- Periodicals; Carbohydrates -- Periodicals; Chimie organique -- Périodiques; Glucides -- Périodiques; Biochemistry; Carbohydrates; Chemistry, Organic; Periodicals; Electronic journals; 507.78
• DOI: 10.1016/j.carres.2022.108725
• Languages: English
• ISSNs: 0008-6215

Abstract

Abstract: In our continuing search of saponins from the plants of Fabaceae family, phytochemical investigation of the roots of Acacia polyacantha, led to the isolation and structural characterization of six undescribed triterpenoid saponins, named polyacosides A-F (1 –6 ). Their structures were established, using extensive analysis by NMR techniques, mainly 1D NMR ( 1 H, 13 C, and DEPT) and 2D NMR (COSY, NOESY, HSQC, TOCSY and HMBC) experiments, HRESIMS and by comparison with the literature data, as 3-O-[β- d -xylopyranosyl-(1 → 4)- [β- d -galactopyranosyl-(1 → 2)-β- d -xylopyranosyl-(1 → 2)]-α- l -arabinopyranosyl]-21-O-[Cis-2-methoxycinnamoyl] machaerinic acid (1 ), 3-O-[β- d -xylopyranosyl-(1 → 4)- [β- d -galactopyranosyl-(1 → 2)-β- d -xylopyranosyl-(1 → 2)]-α- l -arabinopyranosyl]-21-O- [Cis-3, 4-dimethoxycinnamoyl] machaerinic acid. (2 ), 3-O- [β- d -galactopyranosyl-(1 → 2)-β- d -xylopyranosyl-(1 → 2)-α- l -arabinopyranosyl]-21-O- [Trans-4-methoxycinnamoyl] machaerinic acid (3 ), 3-O- [β- d -glucopyranosyl-(1 → 2)-β- d -glucopyranosyl] -21-O- [Cis-3, 4-dimethoxycinnamoyl] machaerinic acid (4 ), 3-O- [β- d -glucopyranosyl-(1 → 2)-β- d -glucopyranosyl] -21-O- [Cis-2-methoxycinnamoyl] machaerinic acid (5 ) and 3-O- [β- d -glucopyranosyl-(1 → 2)-β- d -glucopyranosyl] -21-O- [Trans-4-methoxycinnamoyl] machaerinic acid (6 ). Our findings highlight the presence of methoxycinnamoyl group linked to C-21 of the machaerinic acid aglycone moiety as first report of 21-methoxycinnamoyl-machaerinic acid derivative from the plants of Acacia genus (Fabaceae). This represents therefore a valuable contribution to the chemotaxonomy of the Acacia genus of Fabaceae family, which is known to be a rich source of triterpenoid saponins. Graphical abstract: Image 1 Highlights: Six new acylated triterpenoid saponins isolated from the roots of Acacia polyacantha wild. Their structures were elucidated using chemical methods and spectroscopic analysis. The presence of a methoxycinnamoyl group attached at C-21 of machaerinic acid unit, as aglycon is resported.