title: (+)-Methyl 3β-acet-oxy-13-carb-oxy-19-hy-droxy-11-oxo-C-norolean-18-en-30-oate γ-lactone.
abstract: The title compound, C(33)H(46)O(7), is an unusual oxydation product of the therapeutic agent glycyrrhetinic acid that has, in comparison to the latter, a distinctly altered triterpene structure with one five- and four six-membered carbocycles complemented by a γ-lactone ring with a spiro-junction and a ring double bond. The junction between the five-membered ring C, a cyclo-penta-none ring, and the six-membered ring D, previously in question, was found to be cis, confirming earlier structure assignments based solely on chemical transformations. In the solid state, the compound exhibits five intra- and four inter-molecular C-H⋯O inter-actions with H⋯O distances less than or equal to 2.70 Å and C-H⋯O greater than 100°.
authors.forename: Rawindra
authors.initials: R
authors.lastname: Gaware
authors.forename: Laszlo
authors.initials: L
authors.lastname: Czollner
authors.forename: Ulrich
authors.initials: U
authors.lastname: Jordis
authors.forename: Kurt
authors.initials: K
authors.lastname: Mereiter