Abstract:
Sesquiterpenes are hydrocarbons of the composition, C15H24, which occur in many essential oils. They have been classified by Semmler into four main classes on the basis of the number of rings present in the molecule, deduced by conaideration of the physical constants, and in particular of the molecular refraction. (RL)D (1) Acyclic 69.5 (2) Monocyclic 67.8 (3) Bicyclic 66.1 (4) Tricyclic 64.4 Of the several hundred sesquiterpenes reported in the literature, it is probable that only a small percentage are homogenous substances. The chemistry of sequiterpenes has been reviewed several times in recent years and the following discussion covers the main advances since 1932.
