New compounds, 6-hydroxykarahanaenone and 10-hydroxykarahanaenone, from biotransformation of karahanaenone by CYP2A6.

The in vitro biotransformation of karahanaenone was examined in cytochrome P450 (CYP) 2A6. The biotransformation of karahanaenone by CYP2A6 was investigated by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Karahanaenone was found to be oxidized to two metabolites by CYP2A6. In order to produce large quantity of metabolites by CYP2A6, the biotransformation of karahanaenone by Salmonella typhimurium OY1002/2A6 was investigated. Similarly, two metabolites were confirmed by GC and GC-MS. The structure of metabolites was determined by 1D NMR, 2D NMR, and infrared, as a result there were new compounds, (6R)-hydroxykarahanaenone and 10-hydroxykarahanaenone.