Title: Cnicin
CAS Registry Number: 24394-09-0
CAS Name: (3R)-(3aR,4S,6E,10Z,11aR)-3,4-Dihydroxy-2-methylenebutanoic acid 2,3,3a,4,5,8,9,11a-octahydro-10-(hydroxymethyl)-6-methyl-3-methylene-2-oxocyclodeca[b]furan-4-yl ester
Additional Names: (Z,E)-6a,8a,15-trihydroxygermacra-1(10),4,11(13)-trien-12-oic acid 12,6-lactone 8-(3,4-dihydroxy-2-methylenebutyrate); cynisin; centaurin
Molecular Formula: C20H26O7
Molecular Weight: 378.42
Percent Composition: C 63.48%, H 6.93%, O 29.60%
Literature References: Bitter principle of Cnicus benedictus L., Compositae. Isolation and review: Korte, Bechmann, Naturwissenschaften 45, 390 (1958). Structure: Suchy et al., Tetrahedron Letters no. 10, 5 (1969); Ber. 93, 2449 (1960). Revised structure: Samek et al., Tetrahedron Lett. 1969, 2931. Stereochemistry: Tori et al., J. Chem. Soc. B 1971, 1084.
Properties: Crystals, mp 143°. [a]D20 +158° (c = 2.3 in ethanol). uv max: 220 nm (log e 4.34). Slightly sol in water; freely sol in alcohol. Practically insol in ether.
Melting point: mp 143°
Optical Rotation: [a]D20 +158° (c = 2.3 in ethanol)
Absorption maximum: uv max: 220 nm (log e 4.34) |