Cetraria ornata

Yosioka I, Yamauchi H, Murata K, Kitagawa I (1972d) Coloring substances of a lichen Cetraria ornata, Chem Pharm Bull 20 1082-1084... 

The structures of the pigments secalonic acid A and secalonic acid C, isolated from the lichens Parmelia entotheiochroa (340) and Cetraria ornata (346), have been revised (166). On the basis of further spectral evidence secalonic acids A and C were formulated as the 4,4 -dimers (180) and (181) rather than the 2,2 -derivatives originally proposed. 

Yosioka, L, H. Yamauchi, K. Murata, and I. Kitagawa Colouring Substance of a Lichen Cetraria ornata. Chem. Pharm. Bull. (Japan) 20, 1082 (1972). 

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