Table 2. Inhibition Constants of Tryptamine Psychedelic NPS in Competition Binding Assays for Human 5-HT Receptors^a.

	Ki (nM)
drug	5-HT1A	5-HT1B	5-HT1D	5-ht1e	5-HT2A	5-HT2B	5-HT2C	5-HT5A	5-HT6	5-HT7a
4-PrO-DMT	396	2,410	274	229	336	17	228	325	54	73
4-HO-MET	135	331	197	161	177	12	164	304	70	60
4-AcO-MET	950	960	667	500	514	17	370	-	345	310
4-HO-DET	414	2,242	585	568	400	73	436	1,429	230	826
4-AcO-DET	-	3,817	445	1,162	-	53	875	-	860	1,680
4-HO-MPT	106	224	170	246	114	8	150	664	48	99
4-AcO-MPT	-	9,108	1,900	-	830	22	694	1,805	383	220
4-HO-EPT	163	1,097	644	591	546	62	1,272	1,576	284	438
4-AcO-EPT	-	9,259	1,674	2,225	2,459	43	967	-	1,787	321
4-HO-DiPT	-	-	1,860	-	922	85	-	-	-	-
4-HO-MALT	402	1,500	159	165	357	20	392	492	195	179
4-AcO-MALT	1,141	-	699	775	1,006	9	1,556	1,246	241	582
4-HO-DALT	131	978	432	367	452	63	1,550	2,966	578	454
4-AcO-DALT	582	2,689	2,099	2,116	958	137	824	-	479	406

^aRadioligands used, reference control compound used, and control K_i values for each 5-HT receptor were as follow: 5-HT_1A = [³H]WAY100635 vs 8-HO-DPAT (K_i = 0.6–0.7 nM), 5-HT_1B = [³H]GR125743 vs ergotamine tartrate (K_i = 4–12 nM), 5-HT_1D = [³H]GR125743 vs ergotamine tartrate (K_i = 3–6 nM), 5-ht_1e = [³H]5-HT vs 5-HT (K_i = 5–15 nM), 5-HT_2A = [³H]ketanserin vs clozapine (K_i = 5–8 nM), 5-HT_2B = [³H]LSD vs SB206553 (K_i = 7–12 nM), 5-HT_2C = [³H]mesulergine vs ritanserin (K_i = 1–3 nM), 5-HT_5A = [³H]LSD vs ergotamine tartrate (K_i = 12–37 nM), 5-HT₆ = [³H]LSD vs clozapine (K_i = 7–23 nM), 5-HT_7a = [³H]LSD vs clozapine (K_i = 12–36 nM). Control K_i values represent the range of inhibition constants across 3–4 experiments with triplicate determinations. Dash indicates <50% inhibition in the primary radioligand binding screen.