Separation of Labile Terpenoids by Low Temperature HPLC

Abstract
Semipreparative low temperature HPLC was used to isolate two sesquiterpene hydrocarbons, i. e. anastreptene and β-barbatene, that could not be separated at ambient temperature. A linear relationship was observed between the logarithm of capacity factor and the reciprocal of column temperature. This was consistent with previous reports (4, 5, 8). It could be demonstrated that differences in enthalpy and entropy may cause a temperature-dependent resolution for both compounds. Low temperature H-NMR revealed that separation was not due to a fixation of conformation.