Collect. Czech. Chem. Commun.
1975, 40, 3712-3727
https://doi.org/10.1135/cccc19753712
Conformation of the ring A in 2,3-disubstituted 24-nortriterpenes and the stereochemistry of the opening of 2β,3β-epoxides
J. Klinot, M. Hořejší, M. Buděšínský and A. Vystrčil