Occurrence of polycadinene in fossil and recent resins

Dammars produced by Dipterocarpaceae growing in Southeast Asia are partly composed of a macromolecule with a polycadinene structure. This polymer is the precursor of many specific compounds encountered in crude oils and sediment extracts from South Asia. Until recently there was no evidence for a more widespread geographical occurrence of this resinous polymer. Using different pyrolysis methods it is shown that the polymers present in a resinite from Utah, USA, and in resins contained in resin canals of Eocene fossil fruits from Germany and England are also polycadinenes. The fossil fruits were undoubtedly produced by ancient representatives of mastixioid Cornaceae, a group of plants which was widespread in the Tertiary of Europe and North America and which is not related to Dipterocarpaceae. These findings extend the known occurrence and origin of the sesquiterpenoid type resin polymer. It is to be expected that catagenetic products of these resin polymers should be present in oils, coals, and sediment extracts from areas outside Southeast Asia.