Variegatic acid

Variegatic acid (3,3',4,4'-tetrahydroxypulvinic acid) is a chemical. An orange pigment, it is responsible for the bluing reaction seen in many bolete mushrooms when they are injured. When mushroom tissue containing variegatic acid is exposed to air, the chemical is enzymatically oxidized to blue chinonmethid anions.

It was first isolated from Suillus variegatus. It has strong antioxidant properties, and a nonspecific inhibitory effect on cytochrome P450 enzymes. A total synthesis was reported in 2001 that uses a Suzuki cross coupling reaction.