Bipiperidinyl 4-ANPP is structurally similar to known opioids.

AZ 12488024 (AZD7268) is a SNC80.

AP-238 is a a new synthetic opioid (NSO), and acts as an agonist for μ-opioid receptor (MOR) with an EC50 of 248 nM. AP-238 exhibits analgesic activity.

Alvimopan metabolite hydrochloride is a peripherally restricted Opioid Receptor antagonist that inhibits the amplitude of electrically evoked contractions and spontaneous mechanical activity in guinea pig ileum.

Allyphenyline oxalate (compound 9) can enhance the analgesic effect of Morphine. The pKi values ​​of Allyphenyline for α2A, α2B and α2C are 7.24, 6.47 and 7.07, respectively.

AH-8533 is a opioid agent.

AH 7959 is an orally active N-substituted cyclohexyl methyl benzamide compound that has analgesic effects, the oral and subcutaneous ED50 of AH 7959 in mice is greater than 1 g/kg.

5′-Guanidinonaltrindole (GNTI) is a selective kappa opioid receptor antagonist.

3-Carboxamidonaltrexone (example 32) is a opioid receptor binding compound with Ki values of 1.9 nM, 110 nM, and 22 nM for μ-opioid receptor, δ-opioid receptor, and K-opioid receptor, respectively.

3,4-Difluoro U-50488 hydrochloride is a utopioid.

3,4-Difluoro propyl U-47700 is a utopioid.

3,4-Difluoro isopropyl U-47700 is a utopioid.

2-Naphthyl U-47700 is a utopioid.

2,4-Difluoro U-48800 hydrochloride is a utopioid.

(S)-MCOPPB is the S-form of MCOPPB.

(+)-Norpropoxyphene maleate is an opioid metabolite and is a metabolite of Propoxyphene.

(-)-9-Hydroxycorynantheidine (9-O-Desmethyl mitragynine), the 9-demethyl analogue of Mitragynine, is a selective and partial agonist of μ-opioid receptor. (-)-9-Hydroxycorynantheidine inhibits electrically stimulated twitch contraction in guinea-pig ileum.

(Rac)-SNC80 is a racemate of SNC80. SNC80 (NIH 10815) is a potent, highly selective and non-peptide δ-opioid receptor agonist with a Ki of 1.78 nM and an IC50 of 2.73 nM. SNC80 shows antinociceptive, antihyperalgesic and antidepressant‐like effects. SNC80 has the potential for multiple headache disorders treatment.

LY2940094 (BTRX-246040) tartrate is a potent, brain penetrant, selective and orally available N/OFQ peptide (NOP) receptor antagonist with high affinity (Ki=0.105 nM) and antagonist potency (Kb=0.166 nM). LY2940094 tartrate reduces Ethanol self-administration and Ethanol seeking in animal models.

Icalcaprant is a kappa-opioid receptor antagonist.

ZYKR1 is a potent, and peripherally restricted kappa opioid receptor (KOR)-selective agonist with EC50 of 0.061 nM in cAMP assays, highly selective over the mu and delta opioid receptors (EC50>10 μM).

PN6047 is an orally bioavailable, G protein-biased and selective δ opioid agonist with pKi of 7.25, fully engages G protein signaling but is a partial agonist in both the arrestin recruitment and internalization assays.

PIPE-3297 is a fully efficacious and selective kappa opioid receptor (KOR) agonist with functional GTPγS EC50 of 1.1 nM, Emax=91%, does not elicit β-arrestin-2 recruitment functional response.

A potent, competitive antagonist for μ, κ, δ, and σ-opioid receptors with Ki of 0.0825 nM, 0.509 nM, and 8.02 nM, for MOR, KOR, and DOR, respectively.

MP135 is a potent, μ-δ opioid receptor heteromer-selective agonist with EC50 of 0.8 nM in GTPγS assays, shows functional selectivity for μ-δ heteromers over homomeric μOR and δOR and low β-arrestin2 recruitment activity.

LY2817412 is a potent, selective andorally active nociceptin/orphanin FQ (NOP) receptor antagonist with Ki of 0.176 nM, Kb of 0.273 nM in functional assay of receptor-mediated G-protein activation using [35S]-GTPγS binding.

AT-039 is a potent, selective agonist of nociceptin opioid peptide (NOP) receptor, AT-039 is useful for treatment of hypertension and/or volume overload/hyponatraemic states.

DAMGO (DAGO) is a potent and selective μ opioid receptor agonist with ki of 17 nM.

DS34942424 is an orally potent analgesic without mu opioid receptor agonist activity.

EST73502 is a selective, orally active and blood-brain barrier (BBB) penetrant dual μ-opioid receptor (MOR) agonist and σ1 receptor (σ1R) antagonist, with Kis of 64 nM and 118 nM for MOR and σ1R, respectively. EST73502 has antinociceptive activity.