Title: Alantolactone
CAS Registry Number: 546-43-0
CAS Name: [3a
R-(3aa,5b,8ab,9aa)]-3a,5,6,7,8,8a,9,9a-Octahydro-5,8a-dimethyl-3-methylenenaphtho[2,3-
b]furan-2(3
H)-one
Synonyms: 8b-hydroxy-4a
H-eudesm-5-en-12-oic acid g-lactone; helenin; alant camphor; elecampane camphor; inula camphor
Molecular Formula: C15H20O2
Molecular Weight: 232.32
Percent Composition: C 77.55%, H 8.68%, O 13.77%
Literature References: A terpene from roots of
Inula helenium L.,
Compositae: Kallen,
Ber. 6, 1506 (1873);
9, 154 (1876); Ruzicka
et al., Helv. Chim. Acta 14, 397, 1090 (1931);
16, 268 (1933). Structure: Marshall, Cohen,
J. Org. Chem. 29, 3727 (1964). Stereoselective synthesis: Marshall
et al., J. Am. Chem. Soc. 88, 3408 (1966).
Properties: Crystals from alcohol, mp 78-79°. bp 275°. [a]D +175° (chloroform). uv max (ethanol): 212 nm (e 9500). Volatile with steam. Freely sol in alcohol, chloroform, benzene, ether, oils. Practically insol in water.
Melting point: mp 78-79°
Boiling point: bp 275°
Optical Rotation: [a]D +175° (chloroform)
Absorption maximum: uv max (ethanol): 212 nm (e 9500)