Title: Emetine
CAS Registry Number: 483-18-1
CAS Name: 6¢,7¢,10,11-Tetramethoxyemetan
Synonyms: cephaeline methyl ether
Molecular Formula: C29H40N2O4
Molecular Weight: 480.64
Percent Composition: C 72.47%, H 8.39%, N 5.83%, O 13.32%
Literature References: Principal alkaloid of ipecac, the ground roots of
Uragoga ipecacuanha (Brot.) Baill.
Rubiaceae; occurs naturally as (-)-form. Extraction procedures: E. Merck,
BIOS Final Report No. 766 (1947); F. E. Hamerslag,
Technology and Chemistry of Alkaloids (New York, 1950) chapter XI; Stoll, Jucker in
Ullmanns Encyklop?die der technischen Chemie 3, Aufl., Bd. III (München-Berlin, 1953) p 231;
Beilstein 2nd suppl.
vol. 23, 449. Structure: Robinson,
Nature 162, 524 (1948); Janot,
Bull. Soc. Chim. Fr. 1949, 185. Stereochemistry: Battersby,
Chem. Ind. (London) 1958, 1324; Battersby, Garrett,
J. Chem. Soc. 1959, 3512; Van Tamelen
et al., J. Am. Chem. Soc. 81, 6214 (1959). Total synthesis: Evstigneeva
et al., Proc. Acad. Sci. USSR 75, 539 (1950); Van Tamelen
et al., J. Am. Chem. Soc. 91, 7359 (1969); T. Kametani
et al., J. Chem. Soc. Perkin Trans. 1 1979, 1211. Alternate syntheses: Burgstahler, Bithos,
J. Am. Chem. Soc. 82, 5446 (1960); Openshaw, Whittaker,
J. Chem. Soc. 1963, 1461; S. Takano
et al., J. Org. Chem. 43, 4169 (1978); T. Fujii, S. Yoshifuji,
Tetrahedron 36, 1539 (1980).
See also Clark
et al., US 3102118 (1963 to Glaxo). Review of syntheses: M. Shamma,
The Isoquinoline Alkaloids (Academic Press, New York, 1972) pp 426-457. Toxicity: Radomski
et al., J. Pharmacol. Exp. Ther. 104, 421 (1952); of dihydrochloride: Child
et al., J. Pharm. Pharmacol. 16, 65 (1964).
General review: Grollman, Jarkovsky, in
Antibiotics Vol. 3, J. W. Corcoran, F. E. Hahn, Eds. (Springer-Verlag, New York, 1975) pp 420-435. Comprehensive description: L. V. Feyns, L. T. Grady,
Anal. Profiles Drug Subs. 10, 289-335 (1981).
Properties: White, amorphous powder. mp 74°. Turns yellow on exposure to light and heat. [a]D20 -50° (c = 2 in CHCl3). Strong alkaline reaction. pK1 5.77; pK2 6.64. Freely sol in methanol, ethanol, acetone, ethyl acetate, ether, chloroform. Sparingly sol in water, petr ether. Moderately sol in dil ammonium hydroxide, but sparingly in solns of KOH and NaOH. Absorption spectrum: Bayard,
Chem. Zentralbl. 1943, II, 305. LD50 i.p. in rats: 12.1 mg/kg (Radomski).
Melting point: mp 74°
pKa: pK1 5.77; pK2 6.64
Optical Rotation: [a]D20 -50° (c = 2 in CHCl3)
Toxicity data: LD50 i.p. in rats: 12.1 mg/kg (Radomski)
Derivative Type: Dihydrochloride
CAS Registry Number: 316-42-7
Synonyms: Emetine hydrochloride
Trademarks: Hemometina (Cusi)
Molecular Formula: C29H40N2O4.2HCl
Molecular Weight: 553.56
Percent Composition: C 62.92%, H 7.65%, N 5.06%, O 11.56%, Cl 12.81%
Properties: Contains water of crystallization varying from 3 to 8 H2O. Clusters of needles after drying at 105°, mp 235-255° (dec). [a]D +11° (c = 1) to [a]D +21° (c = 8), calculated for the anhydrous salt. One gram of the hydrated salt dissolves in about 7 ml water. pH of aq soln (1 g in 50 ml) 5.6. Sol in alcohol. Solid and solutions turn yellow on exposure to light or heat. LD50 (calculated as base) in mice (mg/kg): 32 s.c.; 30 orally (Child).
Melting point: mp 235-255° (dec)
Optical Rotation: [a]D +11° (c = 1) to [a]D +21° (c = 8)
Toxicity data: LD50 (calculated as base) in mice (mg/kg): 32 s.c.; 30 orally (Child)
Derivative Type: Emetamine
CAS Registry Number: 483-19-2
CAS Name: 1¢,2¢,3¢,4¢-Tetradehydro-6¢,7¢,10,11-tetramethoxyemetan
Synonyms: tetradehydroemetine
Molecular Formula: C29H36N2O4
Molecular Weight: 476.61
Percent Composition: C 73.08%, H 7.61%, N 5.88%, O 13.43%
Literature References: Occurs in small amounts in ipecac. Isoln: Pyman,
J. Chem. Soc. 111, 419 (1917). Structure: Battersby
et al., J. Chem. Soc. 1959, 1744. Synthesis:
eidem, J. Chem. Soc. 1961, 3899.
Properties: Crystals from ether, mp 142-143°. uv max (ethanol): 236, 283 nm (log e 4.85, 3.86).
Melting point: mp 142-143°
Absorption maximum: uv max (ethanol): 236, 283 nm (log e 4.85, 3.86)
Therap-Cat: Antiamebic.
Therap-Cat-Vet: Hydrochloride has been used as an antiamebic and in lung worm infection.
Keywords: Antiamebic.