Table 3.

Tri- and tetra-substituted coumarins and their CAR activation.

Compound	R1	R2	R3	R4	CAR Activation Fold a	Ref
54	-OCH3	-OCH3	-OCH3	H	−19% ± 3%	[39,44]
55 fraxinol	-OCH3	-OH	-OCH3	H	−17% ± 2%	[39]
56	-OCH3	H	-OCH3	-OCH3	−14% ± 2%	[39]
57 leptodactylone	-OCH3	H	-OCH3	-OH	2% ± 4%	[39]
58	H	-OCH3	-OCH3	-OCH3	0% ± 2%	[52]
59	H	-OCH3	-OCH2O-		36% ± 23%	[17,53]
60	-OCH3	-OCH3	-OCH2O-		12% ± 1%	[17,53]

^a CAR activation fold was calculated: (the luminescence value of the tested compound- the luminescence value of scoparone)/the luminescence value of scoparone (as positive control) × 100%.