Longipinene derivatives from Santolina viscosa.

The neutral fraction of the hexane extract of the aerial parts of Santolina viscosa afforded eight new longipinene derivatives (1-8), oblongifolidiol (9), and several other known compounds. The structures of 1-8 were established by spectroscopic methods and chemical transformations. The vulgarone A-type structure previously reported for oblongifolidiol has been reassigned as the longipinene derivative 9 using 2D NMR, chemical correlations, and X-ray diffraction.