Carotenoid pigment; stereoisomer of chrysanthemaxanthin, q.v. Often found in plants, but in minute amounts only and never as a principal pigment. Isoln from Ranunculus acris L., Ranunculaceae: Kuhn, Brockmann, Z. Physiol. Chem. 213, 192 (1932). Structure: Karrer, Rutschmann, Helv. Chim. Acta 25, 1144 (1942). Partial synthesis: Karrer, Jucker, ibid. 28, 300 (1945). Absolute configuration: H. Cadosch et al., ibid. 61, 783 (1978).