Triterpene glycosides of Thalictrum squarrosum. II. Molecular and crystal structure of squarrofuric acid

The structure of squarrofuric acid (an artifactual genin fromThalictrum squarrosum) has been confirmed by x-ray structural analysis and the configurations of the C13, C14, C17, C20, and C22 asymmetric centers have been established, which has enabled this compound to be assigned to the lanostane series with the following structure: 3,30-dihydroxy-20(S),22(S)-22,25-epoxylanost-9(11)-en-21-oic acid.Novosibirsk Institute of Organic Chemistry, Siberian Branch of the USSR Academy of Science. Irkutsk Institute of Organic Chemistry, Siberian Branch of the USSR Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 533–537, July–August, 1987.