TABLE 1.

Binding Affinities of Aminothiazolomorphinans to MOR, KOR and DOR.^a

Compound	Ki = (nM) ± SEM		[3H]naltrindole (δ)	Selectivity
	[3H]DAMGO (μ)	[3H]U69,593 (κ)		μ/κ	δ/κ
Levorphanolb	0.21 ± 0.02	2.3 ± 0.3	4.2 ± 2.3	0.091	1.8
Cyclorphanb	0.062 ± 0.003	0.034 ± 0.002	1.9 ± 0.1	1.8	56
Butorphane	0.23 ± 0.01	0.079 ± .003	5.9 ± 0.6	2.9	75
1a (ATPM)b	1.5 ± 0.2	0.049 ± 0.005	29 ± 2	31	590
1b (MCL-442)c	3.0 ± 0.062	0.066 ± 0.0037	25 ± 1.5	45	380
1c (MCL-439)c	4.7 ± 0.023	0.15 ± 0.000	43 ± 6.5	31	290
1d (MCL-437)c	57 ± 3.9	13 ± 1.1	750 ± 64	4.4	58
7 (MCL-741)d	6.7 ± 0.71	1.9 ± 0.12	13 ± 1.4	3.5	6.8
8 (MCL-420)d	0.12 ± 0.0069	0.072 ± 0.0039	0.23 ± 0.012	1.7	3.2
9 (MCL-744)	0.085 ± 0.010	0.17 ± 0.025	0.65 ± 0.043	0.50	3.8
10 (MCL-745)	6.6 ± 0.63	9.0 ± 1.2	4.6 ± 0.16	0.73	0.51
11 (MCL-743)	9.6 ± 0.39	3.6 ± 0.35	1.6 ± 0.16	2.7	0.44
12 (MCL-742)	0.14 ± 0.015	0.084 ± 0.0026	0.43 ± 0.018	1.7	5.1

^aMembranes from CHO cells, expressing either human KORs, MORs, or DORs, were incubated with 12 different concentrations of the compounds in the presence of receptor-specific radioligands at 25°C, in a final volume of 1 mL of 50 mM Tris-HCl, pH 7.5. Nonspecific binding was determined using 10 μM naloxone.

^bRef. 18.

^cRef. 19.

^dRef. 23.