Title: Monocrotaline
CAS Registry Number: 315-22-0
CAS Name: (13a,14a)-14,19-Dihydro-12,13-dihydroxy-20-norcrotolanan-11,15-dione
Synonyms: crotaline; MCT
Manufacturers' Codes: NSC-28693; NCI-C56462
Molecular Formula: C16H23NO6
Molecular Weight: 325.36
Percent Composition: C 59.06%, H 7.13%, N 4.30%, O 29.50%
Literature References: Toxic pyrrolizidine alkaloid isolated from
Crotalaria spp. Isoln: R. Adams, E. F. Rogers,
J. Am. Chem. Soc. 61, 2815 (1939); R. B. Tinker, W. M. Lauter,
Econ. Bot. 10, 254 (1956); C. C. J. Culvenor, L. W. Smith,
Aust. J. Chem. 16, 239 (1963). Structure: R. Adams
et al., J. Am. Chem. Soc. 74, 5612 (1952). Stereochemistry: D. J. Robins, D. H. G. Crout,
J. Chem. Soc. C 1969, 1386. Crystal structure: H. Stoeckli-Evans,
Acta Crystallogr. B35, 231 (1979). Stereoselective synthesis: H. Niwa
et al., Tetrahedron 48, 10531 (1992). ELISA measurment: M. A. Bober
et al., Toxicon 27, 1059 (1989). Toxicology: P. M. Newberne
et al., Toxicol. Appl. Pharmacol. 18, 387 (1971); R. A. Roth
et al., ibid. 60, 193 (1981). Review of carcinogenicity studies:
IARC Monographs 10, 291-302, 333-342 (1976). Comprehensive reviews: L. Bull
et al., The Pyrrolizidine Alkaloids (North-Holland, Amsterdam, 1968) 293 pp; D. J. Robins,
Fortschr. Chem. Org. Naturst. 41, 115-203 (1982). Review of pulmonary toxicity: D. W. Wilson
et al., Crit. Rev. Toxicol. 22, 307-325 (1992).
Properties: White prisms from abs ethanol, mp 197-198° (dec). [a]D26 -54.7° (c = 5.054 in chloroform). Also reported as colorless crystals from ethanol, mp 187-190° (dec). [a]D12 -55.0° (c = 0.16 in CHCl3). uv max (96% ethanol): 217 nm (log e 3.32), Simánek
et al., Collect. Czech. Chem. Commun. 34, 1832 (1969). LD50 orally in rats: 71 mg/kg (Newberne).
Melting point: mp 197-198° (dec); mp 187-190° (dec)
Optical Rotation: [a]D26 -54.7° (c = 5.054 in chloroform); [a]D12 -55.0° (c = 0.16 in CHCl3)
Absorption maximum: uv max (96% ethanol): 217 nm (log e 3.32), Simánek
et al., Collect. Czech. Chem. Commun. 34, 1832 (1969)
Toxicity data: LD50 orally in rats: 71 mg/kg (Newberne)
Derivative Type: Hydrochloride
Molecular Formula: C16H23NO6.HCl
Molecular Weight: 361.82
Percent Composition: C 53.11%, H 6.69%, N 3.87%, O 26.53%, Cl 9.80%
Properties: mp 184° (dec). [a]D28 -38.4° (c = 5.2 in water).
Melting point: mp 184° (dec)
Optical Rotation: [a]D28 -38.4° (c = 5.2 in water)
Derivative Type: Methiodide
Molecular Formula: C16H23NO6.CH3I
Molecular Weight: 467.30
Percent Composition: C 43.69%, H 5.61%, N 3.00%, O 20.54%, I 27.16%
Properties: mp 205° (dec). [a]D28 +23.4° (c = 3.1 in methanol).
Melting point: mp 205° (dec)
Optical Rotation: [a]D28 +23.4° (c = 3.1 in methanol)
Use: For inducing pulmonary diseases in rats.
