The IC₅₀ values of the prepared compounds 15–22 against OX1R and OX2R: part 2.

Compd	A-Ring	IC50 (μM)
		OX1R	OX2R
15	3-Fluorophenyl	1.98	1.65
16	4-Methoxyphenyl	2.29	5.11
17	Phenyl	8.58	1.52
18	4-tert-Butylphenyl	NAa	1.32
19	2,3-Dihydrobenzo[b][1,4]dioxin-6-yl	0.20	1.78
20	4-Fluorophenyl	NAa	NAa
21	2-Fluorophenyl	NAa	3.87
22	p-Acetamidophenyl	1.33	2.05
Suvorexant	—	0.14	0.15

^aNo inhibitory activity.