URB937.

URB937 is an O-aryl carbamate that inhibits FAAH, the enzyme that degrades anandamide. On rat brain membranes, its IC50 is 26.8 nM; monoacylglycerol lipase is not inhibited (IC50 above 100 µM) and tissue 2-AG does not change. The molecule does not bind CB1 or CB2 itself: its action goes through accumulation of anandamide, and the antinociceptive effect seen in mice was blocked by CB1 antagonists but not by a CB2 antagonist (Clapper et al. 2010). Its particularity is to be a substrate of the efflux transporter ABCG2, which pushes it out of the brain and spinal cord: in mice, the dose inhibiting half of FAAH is 0.2 mg/kg in liver against 40 mg/kg in brain (a 200-fold ratio), and, at 25 mg/kg intraperitoneally, the compound reached the brain and spinal cord of Abcg2-deficient mice but not of wild-type mice (Moreno-Sanz et al. 2011). This peripheral restriction made it a tool to study the role of peripheral anandamide in nociception: in rodents, URB937 attenuated pain-like behaviours in models of nerve injury and inflammation without access to the central nervous system, effects prevented by CB1 blockade (Clapper et al. 2010). In pregnant females, access to placental and fetal tissues is restricted (Moreno-Sanz et al. 2012). The literature found is preclinical; no clinical trial registered on ClinicalTrials.gov was found and human data are lacking.

Source

An entirely synthetic compound with no known natural occurrence: it was designed as a peripherally restricted FAAH inhibitor, by adding polar groups to the proximal phenyl ring of URB597, a FAAH inhibitor that crosses the blood-brain barrier (Clapper et al. 2010).

No biosynthesis: URB937 is produced by no organism. It is a synthetic derivative of the aryl carbamate URB597 carrying an extra hydroxyl, which makes it a substrate of an efflux transporter (Clapper et al. 2010).

European Union

The substance is not listed in the Annex to Council Framework Decision 2004/757/JHA (consolidated version of 12 January 2026), which lists the new psychoactive substances controlled at European Union level; control is a matter for national law. No marketing authorisation was found: the compound is described only in the research literature.

France

Not classified: URB937, a biphenyl carbamate, is not on the ANSM consolidated list of narcotics (updated 16/02/2026) and its structure falls within none of the generic families of that list. No marketing authorisation was found.

Sources: EUR-Lex, UNODC, CND, ANSM, IUPHAR/BPS, ChEBI, EUDA. Our method.

Family

ECS pharmacological tool › Enzyme inhibitor

Verification

Classification, sources and binding values checked on 20 October 2026; text read against its sources and Wikipedia.

Wikipedia (English)

No dedicated article.

1. 1Clapper JR et al. Anandamide suppresses pain initiation through a peripheral endocannabinoid mechanism. Nat Neurosci, 2010 (new tab)PMID 20852626
2. 2Moreno-Sanz G et al. The ABC membrane transporter ABCG2 prevents access of FAAH inhibitor URB937 to the central nervous system. Pharmacol Res, 2011 (new tab)PMID 21767647
3. 3Moreno-Sanz G et al. Pharmacological characterization of the peripheral FAAH inhibitor URB937 in female rodents: interaction with the Abcg2 transporter in the blood-placenta barrier. Br J Pharmacol, 2012 (new tab)PMID 22774772
4. 4Moreno-Sanz G et al. Synthesis and structure-activity relationship studies of O-biphenyl-3-yl carbamates as peripherally restricted fatty acid amide hydrolase inhibitors. J Med Chem, 2013 (new tab)PMID 23822179
5. 5Vozella V et al. Pharmacokinetics, pharmacodynamics and safety studies on URB937, a peripherally restricted fatty acid amide hydrolase inhibitor, in rats. J Pharm Pharmacol, 2019 (new tab)PMID 31579946
6. 6PubChem, URB937, CID 53394762 (identifiers and properties) (new tab)

SMILES

C1CCC(CC1)NC(=O)OC2=CC(=C(C=C2)O)C3=CC(=CC=C3)C(=O)N

Machine-readable entry (JSON)

LLM ingestion format: a structured superset of the entry (identifiers, binding, versioned legal status). Full corpus.