Table 3.

Structures of the active compounds.

		Substituent
Flavones	Compounds	$R_1$	$R_2$	$R_3$	$R_4$
	Apigenin	H	OH	H	OH
	Luteolin	H	OH	OH	OH
	Baicalein	OH	OH	H	H
	Baicalin	OH	Glucuronide	H	H
Flavonols
	Kaempferol	OH		H	H
	Quercetin	OH		OH	H
	Myricetin	OH		OH	OH
	Rutin	Rutinose		H	OH
Flavanones
	Naringenin	OH		H	OH
	Hesperetin	OH		OH	$O{CH}_3$
	Naringin	Neohesperidose		H	OH
	Hesperidin	Rutinoside		OH	$O{CH}_3$
Isoflavone
	Genistein	OH	H
Flavan-3-ols
	Catechin				H
	Chlorogenic acid