Three new triterpenes, named 25-O-acetylcimigenol (I), dehydroxy-15-O-methyl cimigenol (VI) and 15-O-methylcimigenol (VIII), were obtained from the hypogenous part of Cimicifuga acerina and their structures were determined. I, mp 193-194°, [α]
15D+39.3°, C
32H
50O
6, leads to cimigenol (II) and cimigenyl diacetate (V), of which structures were determined, by hydrolysis and acetylation, respectively. I forms a diketo derivative (III), mp 211-212°, C
32H
46O
6 and a monoketo derivative (IV), mp 175-175.5°, C
32H
48O
6 by·oxidation. VI, mp 222-223°, [α]
7D+38.5°, C
31H
48O
4 forms an acetate (VII), mp 186-187°, [α]
7D+42.6°, C
38H
50O
5, which is obtained from 15-O-methylcimigenol (VIII), on acetylation and dehydration. VIII, mp 199.5-200.5°, [α]
5D+38.9°, C
31H
50O
5, forms an acetate (IX), mp 124-125°, [α]
5D+45.7°, C
33H
52O
6 and a keto derivative (X), mp 156-157°, C
31H
48O
5, by acetylation and oxidation, respectively. VIII, also, is synthesized from cimigenyl diacetate II (V) by reaction with dry methanol and conc. H
2SO
4 following hydrolysis.
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