Novel phenolic biomarker triterpenoids of fossil laticifers in Eocene brown coal from Geiseltal, Germany

Novel phenolic triterpenoids were tentatively identified with known mono-, tri- and tetraaromatic oleanane, ursane, and lupane hydrocarbons and natural product precursors (α-amyrone, α-amyrin) in the extract of Eocene fossil laticifers called “Affenhaar” from the Geiseltal lignites, Germany. The novel phenolic terpenoids are mono- and triaromatic hydroxytriterpenoids (OH at position 1, 2 or 3) of the oleanane, ursane, and lupane classes: hydroxy-24,25-dinoroleana-1,3,5(10),12-tetraene, hydroxy-24,25-dinorlupa-1,3,5(10)-triene, hydroxy-24,25-dinorlupa-1,3,5(10),19(22)-tetraene, hydroxy-24,25,26,27-tetranorursa-1,3,5,7,9,11,13-heptaene, hydroxy-24,25,26,27-tetranoroleana-1,3,5,7,9,11,13-heptaene, and hydroxy-24,25,26,27-tetranorlupa-1,3,5,7,9,11,13-heptaene. The structures of the novel compounds were proposed based on the interpretation of the gas chromatography–mass spectrometry data of the underivatized and silylated total extract.