6alpha-Hydroxypolyporenic acid C is a natural product from Wolfiporia cocos (Schw.) Ryv.

8-hydroxyguanosine (8-OHG) is a marker for measuring the rate of oxidative damage to nucleic acids and lipids.The concentration of 8-OHG in CSF in Parkinson's disease (PD) patients is approximately three-fold that in controls. The concentration of 8-OHG in CSF decreased significantly with the duration of disease. However, the concentration of 8-OHG in serum was not significantly altered in PD patients compared to that in controls.

Methyl 3-indolecarboxylate is a natural product isolated from Heracleum candicans.