Semorphone
Clinical data

ATC code	none
Identifiers
IUPAC name (5α)-4,5-Epoxy-3,14-dihydroxy-17-(2-methoxyethyl)morphinan-6-one
CAS Number	88939-40-6
PubChem CID	5491906
ChemSpider	4590760^Y
UNII	2HD55617I2
CompTox Dashboard (EPA)	DTXSID00933465
Chemical and physical data
Formula	C₁₉H₂₃NO₅
Molar mass	345.395 g·mol⁻¹
3D model (JSmol)	Interactive image
SMILES O=C4[C@@H]5Oc1c2c(ccc1O)C[C@H]3N(CC[C@]25[C@@]3(O)CC4)CCOC
InChI InChI=1S/C19H23NO5/c1-24-9-8-20-7-6-18-15-11-2-3-12(21)16(15)25-17(18)13(22)4-5-19(18,23)14(20)10-11/h2-3,14,17,21,23H,4-10H2,1H3/t14-,17+,18+,19-/m1/s1^Y Key:PBGIBLLOMGURPS-GRGSLBFTSA-N^Y
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Semorphone (Mr 2264) is an opiate analogue that is an N-substituted derivative of oxymorphone.

Semorphone is a partial agonist at μ-opioid receptors. It is around twice the potency of morphine, but with a ceiling effect on both analgesia and respiratory depression^[1] which means that these effects stop becoming any stronger after a certain maximum dose.

It is not currently used in medicine, and is not a controlled drug, although it might be considered to be a controlled substance analogue of oxymorphone on the grounds of its related chemical structure in some jurisdictions such as the United States, Canada, Australia and New Zealand.

References

^ Behne M, Bremerich D, Heinrich J, Schumacher H, Scherer M (1994). "Respiratory effects and tolerability of Mr 2264 Cl. A new opiate partial agonist in comparison with morphine and placebo". European Journal of Clinical Pharmacology. 46 (4): 301–4. doi:10.1007/BF00194395. PMID 7957512. S2CID 33001046.