Long-chain alkenes and alkadienes of eight lichen species collected in Japan

The hydrocarbons of eight lichen species isolated in Japan were analyzed, and diverse mono-, di-, and tri-unsaturated alkenes were detected. The positions of the double bonds of C17 alkadienes (heptadecadiene) and C17–C20 alkenes were determined by mass spectrometry of their dimethyl disulfide adducts. We found that the six lichens containing green algal photobionts were distinguished by the presence of 1,8-heptadecadiene, 6,9-heptadecadiene,...