Hispanane‐Type Diterpenoid and Secoiridoid Glucosides from Viburnum cylindricum

Three hitherto unknown compounds, including one new hispanane‐type diterpenoid glucoside, namely viburnumoside ( 1 ), two new secoiridoid glucosides, 7 α ‐galloyloxysweroside ( 2 ), and 7 β ‐galloyloxysweroside ( 3 ), together with ten known compounds ( 4 – 13 ) were isolated from the ethanol extract of twigs and leaves of Viburnum cylindricum . Their structures were elucidated on the basis of extensive spectroscopic studies, and the absolute configuration of compound 1 was confirmed by the experimental and calculated electronic circular dichroism ( ECD ) data.