Figure 1.

Chemical structures of 1–16.

Compound	R1	R2	R3	R4	R5	R6	R7
(1) 5-Hydroxy-3,7,4′-trimethoxyflavone	OMe	H	H	H	OMe	H	Me
(2) Ayanin	OMe	H	H	OH	OMe	H	Me
(3) Kuatakenin	OMe	H	H	H	OH	H	Me
(4) Rhamnocitrin	OH	H	H	H	OH	H	Me
(5) Ombuin	OH	H	H	OH	OMe	H	Me
(6) Myricetin-3,7,3′,5′-tetramethyl ether	OH	H	H	OMe	OH	OMe	Me
(7) Gardenin D	H	OMe	OMe	OH	OMe	H	Me
(8) 6,8,5′-Tribromoayanin	OMe	Br	Br	OH	OMe	Br	Me
(9) 8-Bromokumatakenin	OMe	H	Br	H	OH	H	Me
(10) 6-Bromokumatakenin	OMe	Br	H	H	OH	H	Me
(11) 6,8,3′,5′-Tetrabromokumatakenin	OMe	Br	Br	Br	OH	Br	Me
(12) Luteolin	H	H	H	OH	OH	H	H
(13) Apigenin	H	H	H	H	OH	H	H
(14) Mearnsetin	OH	H	H	OH	OMe	OH	H
(15) Vitexin	H	H	Glc	H	OH	H	H
(16) Isoorientin	H	Glc	H	OH	OH	H	H