The present report resumes previous data on distribution of n-alkanes and friedelin in plants. These compounds were tested by gas chromatography/mass spectra/tech. computer in 91 species chosen in all botanical taxa. Results have been discussed with regard to taxinomy. The neooleana 3 (5) 12 diene, new triterpenoid in plants, was encountered in Euonymus, Davidia and Diospyros.