Stereocaulon ramulosum

Deriv Methyl planate, needles (MeOH-HjO), mp 58-60 °C, from 2,2-Di-O-methylanziaic acid with CH2N2 in EtjO at 20 °C in 24 h StL Stereocaulon ramulosum (Sw.) Rausch. TLC Rp 0.32 (n-hexane Et20 HCOOH = 13 8 2) Lit Cambie 1968 C.F. Culberson 1972b Elix 1974... 

Baron M, Gorin PAJ, lacomini M (1989) Structural studies on a galactomannan isolated from the lichen Stereocaulon ramulosum. Agric Biol Chem 53 1751-1758... 

Polyporic acid series. J Chem Soc 1041-1045 Cambie RC (1968) The depsides from Stereocaulon ramulosum (Sw.) Rausch. N Z J Sci 11 48-53 Canonica L, Rindone B, Santaniello E, Scolastico C (1972) A total synthesis of mycophenolic acid, some analogues and some biogenetic intermediates. Tetrahedron 28 4395-4404... 

Stereocaulon ramulosum Methyl haematommate Depsides APP 5-lipoxygenase activity Haraldsdottir... 

Hickey BJ, Lumsden AJ, Cole ALJ et al (1990) Antibiotic compounds from New Zealand plants methyl haematommate, an anti-fungal agent from Stereocaulon ramulosum. N Z Nat Sci 17 49-53... 

A number of well-known depsides were synthesised in the manner described above (777), as well as the recently reported compounds 2-0-methylperlatolic acid (241), 2 -0-methylperlatolic and 2 -0-methylanziaic acid (777). An earlier report of the isolation of the related depside, 4-0-demethylplaniaic acid (257) from Stereocaulon ramulosum (41) appears to be an error (84). However this depside has now been shown to co-occur with planiaic acid (258) in the lichens Lecidea lithophila and L. plana (84). The structure of (257) was indicated by microhydrolysis experiments and confirmed by comparison with synthetic material. The synthetic route to (257) is outlined in Scheme 30, and is typical of the approach to all thepara-orcinol depsides. 

Hickey BJ, Lumsden AJ, Cole ALJ, Walker JRL (1990) Antibiotic Compounds from New Zealand Plants Methyl Haematommate, an Anti-fungal Agent from Stereocaulon ramulosum. New Zealand Natural Sciences 17 49... 

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