EXTENDED SATURATED AND MONOAROMATIC TRICYCLIC TERPENOID CARBOXYLIC-ACIDS FOUND IN TASMANIAN TASMANITE

A series of tricyclic terpenoid carboxylic acids (C-20-C-40) was found in the acidic fraction of Tasmanian tasmanite bitumen, occurring as a mixture of stereoisomers with mainly the 13 beta(H),14 alpha(H)- and 13 alpha(H),14 alpha(H)-configurations. These dominant acidic tricyclic consituents have the same carbon skeleton as the ubiquitous tricyclic terpane biomarkers. A novel series of ring-C monoaromatic tricyclic terpenoid carboxylic acids was also characterized. The series ranges from C-19 to C-39 and is the acidic counterpart of the recently described series of monoaromatic tricyclic terpanes.