Biosynthesis of Lichen Substances

Nephroma laevigatum from British Columbia contained the following anthraquinones emodin, 7-chloroemodin, 7-chloro-l-O-methylemodin, 7-chloro-1 -0-methylcitreorosein, 5-chloroemodin, 5-chloro-l-O-methyl-emodin, 5-chloro-l-O-methylcitreorosein and 5-chlorocitreorosein. Feeding experiments with Na[2-14C]-acetate and Na[l-13C]-acetate showed that these anthraquinones are biosynthesized via the polyketide pathway (75). 

Basidiolichenes Eleven analysed Basidiolichenes were free of lichen substances (298) 

Buettia Chemistry of xanthone-containing species of the genus Buellia (504) 

Canoparmelia The genus Canoparmelia was segregated from Pseudoparmelia for chemical reasons (187) 

Cladonia Analysis of 18 species of Cladonia, sect. Helopodium and 5 species of subsect. Foliosae (423) 

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Biosynthesis of lichen substances, products of a symbiotic association, K. Mosbach, Angew. Chem. Int. Ed. Engl., 1969, 8, 240. 

Mosbach, K. On the Biosynthesis of Lichen Substances 2. The Pulvinic Acid Derivative Vulpinic Acid. Biochem. Biophys. Res. Commun. 17, 363 (1964). 

Lichen substances are organic compounds synthesized by lichens. They have long attracted the attention of organic chemists, and their chemistry, structure, properties, and distribution have been treated in detail recently in major works by Asahina and Shibata (1954) and Culberson (1969,1970). This field is also reviewed by Huneck (1968, 1971). Further details on the biosynthesis of lichen substances may be found in Chapter 16 by Mosbach. 

Fox, C. H., and Mosbach, K. (1967). On the biosynthesis of lichen substances. Part 3. Lichen acids as products of a symbiosis. Acta Chem. Scand. 21, 2327. 

Yamazaki, M., and Shibata, S. (1966). Biosynthesis of lichen substances. II. Participation of Cj-unit to the formation of -orcinol type lichen depside. Chem. Pharm. Bull. 14,96. 

Chapter 16. Biosynthesis of Lichen Substances Klaus Mosbach... 

Only a few papers concerning the biosynthesis of lichen substances have been published between 1984 and 1998. Biogenesis of the diphenyl derivative contortin (see Scheme 183) very likely proceeds by phenolic coupling of two molecules of C-methylphloracetophenone methyla-... 

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