Table 1.

Serotonin receptor binding affinities and activation potencies of 4-alkoxy-substituted 2,5-dimethoxyphenethylamines and amphetamines.

		h5-HT1A	h5-HT2A			h5-HT2B		h5-HT2C	Selectivity (binding ratios)
		Receptor binding K i ± SD [nM] [3H]8-OH-DPAT	Receptor binding K i ± SD [nM] [3H]ketanserin	Activation potency EC50 ± SD [nM]	Activation efficacy max ± SD [%]	Activation potency EC50 ± SD [nM]	Activation efficacy max ± SD [%]	Receptor binding K i ± SD [nM] [3H]mesulgerine	5-HT2A/5-HT1A	5-HT2A/5-HT2C
4-alkoxy-substituted 2,5-dimethoxyphenethylamines
6	2C-O-2	3600 ± 400	670 ± 90	16 ± 3	50 ± 10	49 ± 44	85 ± 17	2300 ± 1200	5.4	3.4
7	2C-O-3	2700 ± 200	40 ± 8	0.5 ± 0.3	70 ± 4	68 ± 21	50 ± 22	150 ± 30	68	3.8
8	2C-O-16	4500 ± 500	140 ± 40	4.9 ± 2.5	84 ± 4	120 ± 70	42 ± 13	470 ± 40	32	3.4
9	2C-O-21	5500 ± 0	1700 ± 600	53 ± 15	44 ± 17	900 ± 450	39 ± 26	3600 ± 1900	3.2	2.1
10	2C-O-21.5	2900 ± 200	1000 ± 100	2600 ± 1600	30 ± 8	480 ± 260	28 ± 23	4200 ± 1500	2.9	4.2
11	2C-O-22	3300 ± 200	440 ± 60	460 ± 140	35 ± 8	250 ± 10	28 ± 20	1900 ± 400	7.5	4.3
12	2C-O-27	2700 ± 100	8.1 ± 1	76 ± 80	36 ± 16	480 ± 190	39 ± 16	110 ± 50	333	14
4-alkoxy-substituted 2,5-dimethoxyamphetamines
13	MMALM	NA	61 ± 0	1.5 ± 0.1	95 ± 4	29 ± 13	90 ± 13	290 ± 110	>92	4.8
14	MALM	>5600	150 ± 0	2.9 ± 0.5	89 ± 10	9.5 ± 3.3	101 ± 6	900 ± 220	>37	6
15	MFEM	>5600	1900 ± 900	330 ± 180	56 ± 36	270 ± 210	41 ± 22	11000 ± 3000	>2.9	5.8
16	MDFEM	>5600	980 ± 620	140 ± 80	48 ± 23	130 ± 80	21 ± 8	6700 ± 2400	>5.7	6.8
17	MTFEM	>5600	460 ± 240	19 ± 1	80 ± 6	200 ± 30	4.8 ± 3.5	2400 ± 800	>12	5.2
18	MIPM	>5600	4400 ± 2100	990 ± 330	47 ± 13	180 ± 120	20 ±14	9030 ± 2390	>1.4	2.1
19	TMA-2	>17000	1300 ± 700	190 ± 90	84 ± 10	270 ± 0	78 ± 5	5300 ± 1600	>13	4.1
Reference substance
	2C-Ba	311±46	6.9 ± 1.8	2.1 ± 0.8	92 ± 8	75 ± 14	52 ± 26	43 ± 4	45	6.2

K_i and EC₅₀ values are given as nM (mean ± SD); activation efficacy (E_max) is given as percentage of maximum ± SD. NA, not assessed.

^aData previously published in (Luethi et al., 2018).