Baicalein

Baicalein is a flavone, a type of flavonoid, originally isolated from the roots of Scutellaria baicalensis and Scutellaria lateriflora. It is also a constituent of Oroxylum indicum and thyme. It is the aglycone of baicalin.

Pharmacology

Baicalein, along with its glucuronide baicalin, is a positive allosteric modulator of the benzodiazepine site and a non-benzodiazepine site of the GABA_A receptor, but with an affinity over 250× lower than diazepam. It displays subtype selectivity for α₂ and α₃ subunit-containing GABA_A receptors.
The flavonoid has been shown to inhibit certain types of lipoxygenases.
Baicalein is an inhibitor of CYP2C9, an enzyme of the cytochrome P450 system that metabolizes drugs in the body.
A derivative of baicalin is a known prolyl endopeptidase inhibitor.