Fustin, sometimes called "dihydrofisetin", is a flavanonol, a type of flavonoid.
It can be found in young fustic (Cotinus coggygria)[1] and in the lacquer tree (Toxicodendron vernicifluum).
[2] Fustin shows protective effects on 6-hydroxydopamine-induced neuronal cell death.
[2] Unlike fisetin, fustin has no double bond in the C-ring.
This makes fustin a flavan, with two stereocenters and four stereoisomers.