Abstract

JANKOWSKI, Christopher K. et al. Unusual Isomerisation of Cubebene. J. Mex. Chem. Soc [online]. 2006, vol.50, n.3, pp.90-95. ISSN 1870-249X.

Some sesquiterpenes extracted from Solidago canadensis L. in methanol underwent apparent isomerisation and the addition of water or methanol when the Soxhlet extraction was replaced by a microwave heating method in polar solvents. The quantity of α-cubebene, one of these sesquiterpenes, during microwave extraction, was dramatically increased. In this study, we present the detailed comparison of two cubebenes subjected to this isomerisation, 6-epi-α-cubebene and α-cubebene, as well as their solvent microwave induced addition products obtained under microwave irradiation in polar solvents. The analysis is supported by high resolution bidimensional NMR (¹H, ¹³C), mass spectroscopy and selected isotopic labelling experiments.

Keywords : Microwave; soxhlet extraction; isomerisation of sesquiter-pene; cubebenes; Solidago canadensis; NMR; tricyclic terpenes.