Phenolic compounds from Plantago asiatica

The four known phenolic compounds, 3,4-dihydroxyphenethyl alcohol-6-O-caffeoyl-β-d-glucoside, acteoside (verbascoside), plantaginin and plantamajoside, and a new phenylpropanoid glycoside, hellicoside, were isolated from the aerial parts of Plantago asiatica, which is used in oriental medicine 'Plantaginis Herba'. The structure of hellicoside was deduced from chemical and spectral evidence to be 3,4,7-trihydroxy-β-phenethyl-O-β-d-glucopyranosyl-(1 → 3)-4-O-caffeoyl-β-d-glucopyranoside. Plantamajoside and hellicoside showed high inhibition of cyclic AMP phosphodiesterase and 5-lipoxygenase. Acteoside showed high inhibition of lens aldose reductase.