Abstract:
Two new triterpenoidal sapogenins of oleanane type, namely glyyunnanprosapogenin D(Ⅴ) and glyyunnansapogenin F(Ⅸ) were isolated from the roots of-
Glycyrrhiza yunnanensis Cheng f. et L. K. Tai, family Leguminosae, collected from Yunnan Province, China. V was obtáined as hexaacetate and dimethyl ester form (Vc), mp 168~170℃, C
56H
78O
22, which gave an aglyconemacedonic acid (V′) and two molecules of glucuronic acid after hydrolysis with hydrochloric acid. The spectral analysis of
13CNMR and
1HNMR showed that Vc had two glycoside residues attached to the aglycone, and therefore the structure of V was established as oleana-11, 13(18)-dien-29-oic acid, 3β, 21α-di-(O-β-D-glucuronic acid) pyranoside.
Ⅸ was obtained as its diacetate and monomethyl ester form (Ⅸc), mp 188~190℃, C
35H
50O
7. The IR,
1HNMR and UV spectra showed that the Ⅸc had a skeleton of oleanane type triterpenoid with heteroannular diene. Ⅸb, diacetate of Ⅸ, unpurifed, was converted to Ⅸf with chromium trioxide in glacial acetic acid. Ⅸf, mp 160~164℃, C
30H
46O
8, was proved to be olean-12-en-11-oxo-3β, 24-diacetoxy-18β-hydroxy-30-oic acid, 30→18β lactone with another carbonyl group at C-15, 16, 21 or 22 by the analysis of
13CNMR,
1HNMR and MS spectra. Ⅸc exhibited a negative absorption in Cd spectrum at 298nm, in accord with C-16-oxo of oleana-11, 13(18)-diene compounds, thus the structure of Ⅸ is 3β, 24-dihydroxy-16-oxo-oleana-11, 13(18)-dien-30-oic acid and that of ixf is 3β, 24-diacetoxy-11, 16-dioxo-18β-hydroxy-olean-12-en-30-oicacid, 30→18β lactone.