Nectandra is a genus of plants especially abundant in neotropical regions including 114 species. It has been demonstrated that some Nectandra plants exhibit antitumoral, antioxidant, antiinflammatory, febrifuge, and hypotensive activities attributed to the presence of alkaloids and neolignans in crude extracts of Nectandra, suggesting good potential as chemotherapeutics. However, sesquiterpene-related compounds are also highly recurrent in some Nectandra, whose structures possess mainly germacrene, eudesmane, and cadinane moieties. Thus, as part of our research on Colombian Lauraceae plants, a carefully phytochemical exploration was carried out on n-hexane-soluble sub-extract from N. amazonum leaves-derived EtOH extract. Repeated chromatography of the above-mentioned sub-extract yielded two new cadinane-related sesquiterpenes (1 – 2), along with two known sesquiterpenes (3 – 6), whose chemical structures were established by analyses of spectroscopic data (1D and 2D NMR, MS) in comparison with spectroscopic data in the literature. The interesting structural features of the new compounds 1 – 2 will be presented on the basis of spectroscopic analyses. A DFT (density functional theory) molecular modeling study at the B3LYP level was separately performed on 1 – 2 starting from a NOESY-resulted configuration in order to support the assignments, due to the conformation-dependent variability of sesquiterpenes. Thus, according to the resulting Boltzmann population analyses for optimized structures of 1 and 2, the lowest stable conformers exhibited a chair-conformed B-ring and supported the NOESY correlations. The novel sesquiterpenes were identified as rel-(4S,6S)-cadina-1(10),7(11)-diene (1) and rel-(1R, 4S, 6S, 10S)-cadina-7(11)-en-10-ol (2). The unusual unsaturation profile of compound 1 suggests further studies which are required to define chemomarkers in order to clarify the biosynthetic role of such sesquiterpenes in Nectandra.