Studies on the Chinese Crude Drug "Forsythiae Fructus."VII. A New Caffeoyl Glycoside from Forsythia viridissima

In addition to a known caffeoyl glycoside of 3, 4-dihydroxyphenethyl alcohol, acteoside (1), a new caffeoyl glycoside of β, 3, 4-trihydroxyphenethyl alcohol, designated as β-hydroxyacteoside (2), was isolated from the fruits of Forsythia viridissima LINDLEY (Oleaceae). The structure of 2 was established as β, 3, 4-trihydroxyphenethyl-O-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-D-glucopyranoside on the basis of analysis of the carbon-13 nuclear magnetic resonance spectrum and chemical evidence.