Color Changes Upon Exposure to Light

The color change in leucorobinetinidin (11) and anhydroleucofisetinidin (13) are included in this mechanism (6, 22). A hydroxy group at position 6 of an 

A few woods that contain light-sensitive compounds, such as the hydroxylated stilbene derivatives as a minor component, turn to a deeper shade by the oxidative polymerization of the extractive (10, 23). It is well known that stilbenes easily isomerize after light absorption. Stilbenes isolated from woods are often reported to form colored compounds upon exposure to light, as in the case of 

---