Cortinarius elegantior

Acidic anthraquinones in which both hydroxy groups in the C-ring have been methylated occur in Cortinarius armillatus and C. miniatopus, while cortinaric acid (313) and its 8-0-methyl ether (314) have been isolated from Cortinarius elegantior where they are partly responsible for the characteristic pink colour produced in the stem base with ammonia. The structures of the latter pigments have been confirmed by synthesis involving chromium trioxide oxidation of the peracetyl derivatives of endocrocin (303) and dermolutein (305), respectively 387). 

Cortinarius elegantior contains among its neutral pigments a pale yellow compound, cortinarin, to which the unique dimeric structure (381) has been assigned from spectroscopic data (Table 32) and from its cleavage with dilute aqueous sodium hydroxide into physcion (290) and emodin-6,8-di-0-methyl ether (292) (387, 515, 617). 

Jagers, E(lisabeth), C. Kilpert, B. Oertel, A. Scherer, B. Steffan, and W. Steglich Farbstoffe aus Cortinarius elegantior. Submitted for publication. 

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