Desmethoxyyangonin or 5,6-dehydrokavain is one of the six main kavalactones found in the Piper methysticum (kava) plant.

Desmethoxyyangonin is a reversible inhibitor of monoamine oxidase B (MAO-B).

[1] Kava is able to increase dopamine levels in the nucleus accumbens[2] and desmethoxyyangonin likely contributes to this effect.

This, along with several other catecholamines, may be responsible for the purported attention-promoting effects of kava.

Unlike the other major kavalactones, desmethoxyyangonin does not appear to act as a GABAA receptor positive allosteric modulator.