Two drimane lactones, valdiviolide and 11-epivaldiviolide, in the form of a 1:1 cocrystal obtained fromDrimys winteriextracts

Abstract

A cocrystal, C15H22O3·C15H22O3, (I), obtained fromDrimys winteri, is composed of two isomeric drimane sesquiterpene lactones, namely valdiviolide, (Ia), and 11-epivaldiviolide, (Ib), neither of which has been reported in the crystal form. Both diastereoisomers present three chiral centres at sites 5, 10 and 11, with anSSRsequence in (Ia) and anSSSsequence in (Ib). O—H...O hydrogen bonds bind molecules into chains running along [\overline{1}20] and the chains are in turn linked by π–π stacking interactions to define planar weakly interacting arrays parallel to (001).