Table 1.

Structure of carotenoid cleavage dioxygenase inhibitors and in vitro inhibition efficacy against LeCCD1a and LeNCED1.

Inhibitor				Inhibition @ 100 μM (%)		Structure
Class	Name	X	Y	LeCCD1a (9,10 / 9′,10′)	LeNCED1 (11′,12′)
Abamine		–	–	35 ± 15a	20
Aryl-C2N	D1	4-OH	H	>95	27
	D2	4-OH	F	>95	29
	D3	3,4-(OH)2	F	>95	4
	D4	4-OMe	F	>95	33
	D5	3,4-(OMe)2	H	>95	8
	D6	3,4-(OMe)2	F	>95	18
	D7	3,4-OCH2O	F	>95	33
Aryl-C3N (class 1)	D8	3,4-(OMe)2	H	61	40
	D14	3,4-(OMe)2	F	nd	nd
	D15	4-OMe	F	70a	24a
Aryl-C3N (class 2)	D12	–	–	26	11
	B2	–	–	47b	13b

^aVan Norman et al. (2014);

^bUnpublished data. All other data from Sergeant et al. (2009). nd, not determined.