Morphinan

Morphinan

Names
Preferred IUPAC name morphinan
Systematic IUPAC name 17-azatetracyclo[7.5.3.01,10.02,7]heptadeca-2,4,6-triene
Other names 1,3,4,9,10,10a-hexahydro-2H-10,4a-(azanoethano)phenanthrene
Identifiers
CAS Number	468-10-0 N
3D model (Jmol)	Interactive image
Beilstein Reference	1375527
ChEBI	CHEBI:35649 N
ChemSpider	5256833 Y
PubChem	11947744
InChI InChI=1S/C16H21N/c1-2-6-13-12(5-1)11-15-14-7-3-4-8-16(13,14)9-10-17-15/h1-2,5-6,14-15,17H,3-4,7-11H2/t14-,15-,16+/m0/s1 Key: INAXVFBXDYWQFN-HRCADAONSA-N
SMILES c12c(cccc1)C[C@H]3NCC[C@]24[C@H]3CCCC4
Properties
Chemical formula	C16H21N
Molar mass	227.35 g·mol−1
Density	1.58 g/cm3
Boiling point	115±0.05 °C (liquid oil)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Morphinan is the prototype chemical structure of a large chemical class of psychoactive drugs, consisting of opiate analgesics, cough suppressants, and dissociative hallucinogens, among others.

Morphinan has a phenanthrene core structure with the A ring remaining aromatic and the B and C rings being saturated, and an additional nitrogen-containing, six-membered, saturated ring, the D ring, being attached to carbons 9 and 13 of the core, and with the nitrogen at position 17 of the composite.

Of the major naturally occurring opiates of the morphinan type—morphine, codeine and thebaine—thebaine has no therapeutic properties (it causes seizures in mammals), but it provides a low-cost feedstock for the synthesis of at least four semi-synthetic opiates, including hydrocodone, hydromorphone, oxycodone and oxymorphone, and, perhaps more significantly, the opioid antagonist naloxone.

The physiological behavior of morphinans (naturally occurring and semi-synthetic derivatives) is thought to be associated with the aromatic A ring, the nitrogen-containing D ring and the "bridge" between these two rings formed by carbons 9, 10 and 11 of the core, with the D ring "above" the core (levo).

Small groups are usually found on morphinan derivatives at carbons 3 and 6.

Many such derivatives have an epoxy group between carbons 4 and 5 (i.e., 4α,5α-epoxy), thereby forming an E ring.

The substitution of certain bulky groups on nitrogen 17 converts an opioid agonist into an opioid antagonist, the most important of which is naloxone, a non-selective opioid antagonist with no opioid agonist properties whatsoever. Additionally, substitution of certain very bulky groups on carbon 6 converts naloxone into a peripherally-selective opioid antagonist with no centrally-selective antagonist properties (naloxegol).