Abstract
The structures of two free triterpenoids, Y and Z, and two saponins, PH and PJ1, isolated from the fresh pericarps of Akebia quinata DECNE. (Lardizabalaceae) were investigated. Y, mp 317-320°, [α]D+62°, was identified with arjunolic acid (I), while Z, mp 303-305°, [α]D+75°, was assigned the structure 20 (29)-dehydro-30-norarjunolic acid (XII) and conventionally named norarjunolic acid. PH, mp 207-210°(decomp.), [α]D+3°, was defined as 28-O-α-L-rha·pyr-(1→4)-β-D-glc·pyr-(1→6)-β-D-glucopyranside (XIX) of XII, and PJ1 was characterized as 28-O-β-D-xyl·pyr-(1→3)-α-L-rha·pyr-(1→4)-β-D-glc·pyr-(1→6)-β-D-glucopyranoside (XXIV') of I. XXIV' is the first arjunolic acid oligoglycoside, and XII and XIX are second to eupteleogenin and eupteleoside, respectively, as a naturally occurring noroleanane derivative and its glycoside.
