DB09173 (Butyrfentanyl or butyrylfentanyl) is a potent, short-acting mu opioid receptor agonist, and an analog of fentanyl, differing by only one methyl group. It has no approved medical indications but is being used for recreational purposes, with cases of fatal overdoses reported in Europe and the United States. Pre-clinical studies of butyrfentanyl are scarce; however, the few available studies suggest that butyrfentanyl is about 30 times less potent than fentanyl itself, and has significant antinociceptive properties, as demonstrated by the acetic acid writhing test in rodents. DB09173 is being abused for its opioid effects. As with other mu-opioid agonists, it can induce respiratory depression which may lead to death and numerous deaths have been reported. No studies of butyrfentanyl dependence or cross-dependence conducted in humans could be identified.

Trifluoromethylphenylpiperazine (TFMPP) acts on serotonin receptors 5-HT1A, 5-HT1B, 5-HT1D, 5-HT2A and 5-HT2C and functions as a full agonist at all sites except the 5-HT2A receptor, where it acts as a weak partial agonist or antagonist. In addition, TFMPP binds to the sodium-dependent serotonin transporter, SERT and evokes the release of serotonin. Besides was shown, that the N-Benzylpiperazine/TFMPP combination produced effects, which crudely mimic those of MDMA, commonly known as ecstasy. The neurophysiological effects of TFMPP in humans was also studied and was shown that TFMPP may affect transmitter systems involved in speeding of interhemispheric communication in the male brain.

ATC-0175 is a potent antagonist with a high affinity for MCH1R and additional affinities for 5-HT1A and 5-HT2B receptors. The receptor binding and the functional assay (MCH-induced increase in [Ca2+]i) indicated that ATC0175 is a noncompetitive antagonist at MCH1Rs. ATC-0175 exhibited anxiolytic effects in numerous animal models of anxiety including the elevated plus-maze test, social interaction test, stress-induced hyperthermia and maternal separation-induced vocalization. ATC-0175 also exhibited antidepressant effects in the forced swimming test. ATC-0175 increased swimming performance without altering climbing behavior, as observed with selective serotonin reuptake inhibitors. ATC0175 has adequate ADME profile (reasonable oral bioavailability and brain penetration) and potent oral activity in animal models. In contrast, ATC-0175 did not affect spontaneous locomotor activity, hexobarbital-induced sleeping time and did not impair rotarod performance. Thus, ATC-0175 may be devoid of unwanted central nervous system side effects, which are sometimes observed with current medications. ATC-0175 has the potential to be effective in the treatment of patients with depression and/or anxiety disorders.

J 113863 is a potent and high selective CKR-1 (CCR1) and CKR-3 (CCR3) chemokine receptor antagonist, which is also behaved as a full agonist of CCR2 and as a very partial agonist of CCR5. This compound was investigated for the treatment of multiple sclerosis and rheumatoid arthritis, but the status of these studies are not known.

(R)-Carteolol is an enantiomer of the drug carteolol that is used to treat glaucoma. (R)-Carteolol is a partial agonist with the high affinity to the beta-adrenoceptors. It was shown, that in the treatment of glaucoma, the therapeutic advantage of the R(+)-isomers is similar to the S(-)-isomers and there is no stereoselectivity between the two enantiomers.

(S)-Carteolol is an enantiomer of the racemic drug carteolol, that is used to treat glaucoma. (S) isomer is a partial agonist with the high affinity to the beta-adrenoceptors. It was shown, that in the treatment of glaucoma, the therapeutic advantage of the R(+)-isomers is similar to the S(-)-isomers and there is no stereo-selectivity between the two enantiomers.