2-Chlorophenyl compounds

Arketamine (developmental code names PCN-101, HR-071603), also known as '(R)-ketamine or (R)-(−)-ketamine', is the (R)-(−) enantiomer of ketamine. Similarly to racemic ketamine and esketamine, the S(+) enantiomer of ketamine, arketamine is biologically active; however, it is less potent as an NMDA receptor antagonist and anesthetic and thus has never been approved or marketed for clinical use as an enantiopure drug. Arketamine is currently in clinical development as a novel antidepressant.

Otenabant (CP-945,598) is a drug that acts as a potent and highly selective CB1 antagonist. It was developed by Pfizer for the treatment of obesity, but development for this application has been discontinued following the problems seen during clinical use of the similar drug rimonabant.

Losigamone (INN) is an investigational drug for the treatment of epilepsy. It has been studied as an add-on treatment for partial seizures. Phase III clinical trials were conducted around the year 2000.

chemical compound

Norketamine, or '''N-desmethylketamine''', is the major active metabolite of ketamine, which is formed mainly by CYP3A4. Similarly to ketamine, norketamine acts as a noncompetitive NMDA receptor antagonist, but is about 3–5 times less potent as an anesthetic in comparison.

thumb|Metabolic pathway of cloniprazepam

Enpiprazole (INN, BAN) is an anxiolytic drug of the phenylpiperazine group that was never marketed. It produces anxiolytic-like effects in animals, though these effects appear to be biphasic and may reverse at high doses. It is known to produce ortho-chlorophenylpiperazine (oCPP) as a metabolite.

Prothioconazole is a synthetic chemical produced primarily for its fungicidal properties. It is a member of the class of compounds triazoles, and possesses a unique toxophore in this class of fungicides. Its effective fungicidal properties can be attributed to its ability to inhibit CYP51A1. This enzyme is required to biosynthesize ergosterol, a key component in the cell membrane of fungi.

Hydroxynorketamine (HNK), or 6-hydroxynorketamine, is a minor metabolite of the anesthetic, dissociative, and antidepressant drug ketamine. It is formed by hydroxylation of the intermediate norketamine, another metabolite of ketamine. As of late 2019, '(2R,6R)-HNK' is in clinical trials for the treatment of depression.

'''N-Ethylnorketamine (ethketamine, NENK, 2-Cl-2'-Oxo-PCE''') is a designer drug which is presumed to have similar properties to ketamine, a dissociative anesthetic drug with hallucinogenic and sedative effects. It has been sold over the internet since around September 2012, and identified in seized drug samples by analytical laboratories in the UK and other European countries.

Ridazolol is a pharmaceutical drug acting as a beta adrenergic receptor antagonist. It was investigated in the 1980 and 90s for its effects on coronary heart disease and essential hypertension (high blood pressure).

Phenazolam, (Clobromazolam, DM-II-90, BRN 4550445) is a benzodiazepine derivative which acts as a potent sedative and hypnotic drug. It was first invented in the early 1980s, but was never developed for medical use. It has been sold over the internet as a designer drug, first being identified in seized samples by a laboratory in Sweden in March 2016.