Title: Violaxanthin
CAS Registry Number: 126-29-4
CAS Name: 5,6:5¢,6¢-Diepoxy-5,5¢,6,6¢-tetrahydro-b,b-carotene-3,3¢-diol
Additional Names: zeaxanthin diepoxide
Molecular Formula: C40H56O4
Molecular Weight: 600.87
Percent Composition: C 79.96%, H 9.39%, O 10.65%
Literature References: Widely distributed carotenoid pigment. Formed in plants from zeaxanthin. Isoln from yellow pansies (Viola tricolor): Kuhn, Winterstein, Ber. 64, 326 (1931). Structure: Karrer et al., Helv. Chim. Acta 14, 1044 (1931); 16, 977 (1933); 19, 1024 (1936); 27, 1684 (1944). Partial synthesis: Karrer, Jucker, ibid. 28, 300 (1945). Abs config: Bartlett et al., J. Chem. Soc. C 1969, 2527. Isoln from Viola tricolor and configuration of the 15-cis-isomer: P. Molnar, J. Szabolcs, Phytochemistry 19, 623 (1980).
Properties: Orange prisms from methanol, reddish-brown acicular crystals from CS2. mp 200°. [a]20Cd +35° (c = 0.08 in chloroform). Absorption max (in alc): 471.5, 442.5, 417.5 nm. Sol in alcohol, methanol, carbon disulfide, ether; almost insol in petr ether.
Melting point: mp 200°
Optical Rotation: [a]20Cd +35° (c = 0.08 in chloroform)
Absorption maximum: Absorption max (in alc): 471.5, 442.5, 417.5 nm
Derivative Type: 15-cis-Isomer
Properties: Irregular yellow plates from benzene/petrol, mp 109°. uv max (benzene): 479, 448, 423, 337 nm (log e 4.91, 4.98, 4.83, 4.77). Friction causes crystals to form orange prisms.
Melting point: mp 109°
Absorption maximum: uv max (benzene): 479, 448, 423, 337 nm (log e 4.91, 4.98, 4.83, 4.77)
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