STEREOCHEMISTRY OF 14-HYDROXY-BETA-CARYOPHYLLENE AND RELATED-COMPOUNDS

The isomerization of beta-caryophyllene (3), under treatment with SeO2 , is described. Chemical correlations, between 3 and 14-hydroxy-beta-c aryophyllene (6) from Juniperus oxycedrus, are established. High resol ution H-1 NMR spectra and analysis by molecular mechanics of 3, 6 and 14-acetoxy-beta-taryophyllene (1) indicate the existence of two confor mational isomers, beta alpha and beta beta, in each compound. At 25 de grees C, the beta alpha conformer predominates in 3 and 7 but the beta beta conformer predominates in 6. The higher percentage of 6 beta bet a possibly derives from an intramolecular hydrogen bond. The treatment of 3, 6 and 7 with m-CPBA generates, in each case, two diastereomeric 4,5-epoxi-derivatives. The epoxides obtained from 6 have been isolate d and analysed separately.