(±)-Salviaprione, a pair of unprecedented abietane-type diterpeniods from Salvia prionitis

(+)-Salviaprione and (-)-salviaprione, a pair of unprecedented abietane-type diterpeniods having an unprecedented 5/6/6 tricyclic ring system with a unique five membered ring A formed by a new C-2/C-11 bond, were isolated from the whole plant of Salvia prionitis. The enantiomeric separation was achieved by HPLC on a chiral column. Their structures and absolute configurations were determined on the basis of 1D and 2D NMR spectra, X-ray diffraction, and electronic circular dichroism (ECD). The possible biogenesis for (+/-)-salviaprione was also postulated. (C) 2015 Elsevier Ltd. All rights reserved.