The essential oil from Peperomia oreophila leaves (Piperaceae) was submitted to fractionation in silica gel column. This separation procedure yielded a fraction composed of a hydrocarbon sesquiterpene mixture which was identified as beta-elemene, alpha-ylangene, alpha-guaiene and beta-selinene. Besides, spathulenol and two sesquiterpenes with the rare ishwarane skeleton: 3-ishwarol and 3-ishwarone were also identified. 3-ishwarone was the major component of the crude oil (78% weight). Since the alcohol obtained was not sufficient to allow a complete structural determination, the original ketone was reduced to 3-ishwarol in order to give additional quantities. After the two sesquiterpenes purification, they were characterized by spectrometric techniques (¹H-¹H COSY, HMQC, HMBC and NOESY).
Peperomia oreophila; essential oil; ishwarane sesquiterpenes; 3-ishwarol; 3-ishwarone
