A previously undescribed phenolic compound from Acanthus ilicifolius L.

Abstract

The plants Acanthus ilicifolius L. (Acanthaceae) are used in Vietnamese folk medicine for the treatment of stomach pain, hepatitis, asthama, and rheumatism. Phytochemical study on the methanol extract of the aerial parts of this plant led to the isolation of seven phenolic compounds, (2R,3R,4R)‐3,4‐dihydroxy‐7‐methoxyflavan 5‐O‐[β‐D‐apiofuranosyl‐(1→6)]‐β‐D‐glucopyranoside (1), quercitrin (2), isoquercitrin (3), kaempferol 3‐O‐α‐L‐arabinopyranoside (4), kaempferol 3‐O‐α‐L‐rhamnopyranoside (5), kaempferol 3‐O‐β‐D‐glucopyranoside (6), and 6‐O‐vanilloylarbutin (7). Among these isolates, compound 1 was previously undescribed compounds. Their chemical structures and the absolute configurations of the new compound were elucidated by 1D‐, 2D NMR, HR‐ESI‐MS and ECD spectroscopic techniques. The known compounds were identified by comparison their NMR spectral data with those reported in the literature.