6150. Metopon

Nomenclature

CAS number: 143-52-2
(5α)-4,5-Epoxy-3-hydroxy-5,17-dimethylmorphinan-6-one; methyldihydromorphinone.
C18H21NO3; mol wt 299.36.
C 72.22%, H 7.07%, N 4.68%, O 16.03%.

Description and references

Semisynthetic opioid analgesic. Prepn from thebaine: L. Small et al., J. Am. Chem. Soc. 58, 1457 (1936). From dihydrocodeinone enol acetate: L. Small et al., J. Org. Chem. 3, 204 (1938). Structure: G. Stork, L. Bauer, J. Am. Chem. Soc. 75, 4373 (1953). Opioid receptor binding study: J. P. McLaughlin et al., Eur. J. Pharmacol. 294, 201 (1995).

Chemical structure

Properties

Needles from alc; sinters 235°, mp 243-245° (evac tube). [α]D24 140.7° (c = 1 in alc). Slightly sol in organic solvents.

Derivative

Hydrochloride.

Nomenclature

CAS number: 124-92-5
C18H21NO3.HCl; mol wt 335.83.
C 64.38%, H 6.60%, N 4.17%, O 14.29%, Cl 10.56%.

Properties

Crystals from alc, mp 315-318° with decompn (evac tube). [α]D24 104.8° (c = 1.002 in water). Freely sol in water. Sparingly sol in alc. Slightly sol in chloroform. Very slightly sol in ether. Insol in benzene. A 1% aq soln has a pH of ≈5.0.

Note

This is a controlled substance (opiate): 21 CFR, 1308.12.