Mansoins C–F, Oligomeric Flavonoid Glucosides Isolated from Mansoa hirsutaFruits with Potential Anti-inflammatory Activity

Continued investigation of the polyphenolic pool of the fruits of Mansoa hirsutaafforded four additional members of the new class of glucosylated oligomeric flavonoids comprising a flavanone core linked to 1,3-diarylpropane C6–C3–C6units. The structures and absolute configurations of mansoins C–F (3–6) were established by analysis of NMR and electronic circular dichroism data. Mansoin C (3) was identified as a diglucosylated heterodimer, whereas mansoins D (4), E (5), and F (6) were identified as triglucosylated heterotrimers, isomeric with mansoin A (1). Mansoin F (6) inhibited TNF-α release by lipopolysaccharide-stimulated THP-1 cells (IC50of 19.3 ± 1.3 μM) and, as with mansoin A (1), reduced the phosphorylation levels of p-65-NF-κB, when assayed at 50 μM. These results indicate that the potential anti-inflammatory properties of mansoin F (6) are probably due to inhibition of the NF-κB pathway and inhibition of TNF-α release.