A new genuine natural product of Cimicifuga triterpenol glycoside, named shengmanol xyloside (7), C
35H
56O
9, mp 244-245.5°C, [α]
22D-10.2°, was isolated from the fresh underground parts of Cimicifuga japonica. The xyloside (7) turned, on a mild treatment with p-toluenesulfonic acid in methanol, into 25-O-methylcimigenol xyloside (6). On enzymatic hydrolysis, 7 yielded its genuine genin, shengmanol (14), C
30H
48O
5·1/2H
2O, mp 153.5-154.5°C, [α]
26D+0.5°, which afforded cimigol (17) on alkali treatment. The xyloside (7) afforded a pentaacetate (16), which was identical with the peracetate of acetyl shengmanol xyloside (2). On the basis of chemical and spectral data, the structure of shengmanol xyloside (7) was proposed to be (23R, 24S)-3β, 15α, 16α-trihydroxy-16, 23 ; 24, 25-diepoxy-9, 19-cyclolanostane 3-O-β-D-xylopyranoside. The contents of cimigenol xyloside (1), acetyl shengmanol xyloside (2), 24-O-acetylhydroshengmanol xyloside (3) and shengmanol xyloside (7) in the fresh underground parts of C. japonica were estimated on the basis of the high-performance liquid chromatography equipped with a RI detector. The total content of 2, 3, and 7 was found to be about two and a half times as much as that of 1, suggesting that the chemically unstable xylosides 2, 3, and 7 are genuine glycosides of some Cimicifuga triterpenol xylosides such as 1 and 6.
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