Rearranged abietane diterpenoids from the root of teucrium polium subsp. vincentinum

Abstract From the root of Teucrium polium subsp. vincentinum (Labiatae) four new rearranged abietane derivatives, teuvincenones A, B, C, and D (1-4, respectively), have been isolated. Two of these compounds, teuvincenones C (3) and D (4), possess a novel hydrocarbon skeleton which contains a cyclopropane ring constituted by the C-3, C-4, and C-18 carbons of the 17(15→16)-abeo-abietane framework. The structures of these diterpenoids were established mainly by spectroscopic means and, in the case of teuvincenones A (1) and C (3), also confirmed by X-ray diffraction analyses.