Cetraria delisei

Solberg YJ (1986) Chemical constituents of the lichen species Cetraria islandica. J Hattori Bot Lab 60 391-406 Solberg YJ (1987) Chemical constituents of the lichens Cetraria delisei, Lobaria pulmonaria, Stereocaulon tomentosum and Usnea hirtUy J Hattori Bot Lab 63 357-366... 

Keto acids (5-keto-15 0,5-keto-16 0,5-keto-18 0,5-keto-21 0,5-keto-23 0) have been isolated from Cetraria delisei and C. islandica (659, 658). Fatty acids from Xanthoriaparietina collected at different elevations (400, 800 and 1300 m a.s.) have been analyzed (576). The main fatty acid at the lowest elevation was 18 2, while 14 0 was the major component at the other two elevations. The isomerization of roccellic acid to threo-roccellic acid (see Scheme 25) has been studied 407). Reduction of dimethyl roccellate with LiAlH4 gave the corresponding diol which yielded two isomeric y-lactones with Jones reagent (see Scheme 25). 

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