A New Lupane-Type Triterpenoid Saponin from Lonicera macranthoides

new lupane-type triterpenoid saponin, named lonimacranthoside A 1 , was isolated from the flower buds of Lonicera macranthoides . The structure of lonimacranthoside A 1 was elucidated as 3 β - O - β -D-glucopyranosyl-(1 → 4)- β -D-glucopyranosyl-(1 → 3)- α -L-rhamnopyranosyl-(1 → 2)- α -L-arabinopyranosyl-23-hydroxy-lup-20(29)-en-28-oic acid 28- O - β -D-glucopyranosyl-(1 → 6)- β -D-glucopyranosyl ester ( 1 ) on the basis of spectral data and chemical evidence. This is the first reported occurrence of a lupane-type saponin in the plant.