ABSTRACT
The essential oil of Schinus terebinthifolius fruits was reinvestigated using GC and GC-MS techniques. Apart from several known compounds three sesquiterpene hydrocarbons with a carbon skeleton exhibiting the rare spiro(cyclopropane) moiety could be isolated by a combination of column chromatography and GLC. Structure assignments were carried out by NMR spectroscopy. These natural products are 9-spiro(cyclopropa)-4,4,8-trimethyl-2-methylenbicyclo[4.3.0]non-1(6)-ene (terebanene), 9-spiro(cyclopropa)-2,4,4,8-tetramethylbicyclo[4.3.0]nona-1,5-diene (teredenene), and (6R*,8R*)-9-spiro(cyclopropa)-2,4,4,8-tetramethylbicyclo[4.3.0]non-1-ene (terebinthene).
Subject(s)
Anacardiaceae/chemistry , Sesquiterpenes/isolation & purification , Gas Chromatography-Mass Spectrometry , Germany , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Oils, Volatile/chemistry , Sesquiterpenes/chemistry , StereoisomerismABSTRACT
The volatile constituents of the roots of Panax ginseng C.A. Meyer have been investigated after hydrodistillation and analysed by means of different analytical methods. Besides several compounds already known three sesquiterpene hydrocarbons have been isolated from the essential oil. Structure elucidation of the bicyclic panaxene as well as of the tricyclic panaginsene and ginsinsene was performed by MS and NMR. They have been identified as (1R*,2S*,5S*)-2-ethenyl-1(1-methylethenyl)-2,6,6-trimethylbicyclo[3.2.0]heptane (panaxene), (1S*,8S*,11R*)-4,7,7,11-tetramethyltricyclo[6.3.0.0(1,5)]undec-4-ene (panaginsene) und (1R*,6R*,7R*)-3,7,10,10-tetramethyltricyclo[4.3.2.0(2,6)]undec-2-ene (ginsinsene).