Investigation of extracts of leaves and twigs of the Ecuadorian medici
nal plant Siparuna macrotepala led characteristically to the isolation
of sesquiterpenes of the cadinane group: cadalene, calamenene, 7-hydr
oxy-calamenene, the dimer of 7-hydroxy-calamenene of S,S-configuration
, and two new compounds: 1-hydroxy-calamenene and 1,6-dimethyltetrahyd
ronaphthalenone-4.