
%0 Journal Article
%A Gill, Melvyn 
%A Morgan, Peter M. 
%A Yu, Jin 
%A White, Jonathan M. 
%T Pigments of Fungi. XLVII. Cardinalic Acid, a New Anthraquinone Carboxylic Acid from the New Zealand Toadstool <emph type="2">Dermocybe cardinalis</emph> and the Synthesis and  X-Ray Crystal Structure of Methyl 1,7,8-Tri-<emph type="2">O</emph>-methylcardinalate
%J Australian Journal of Chemistry
%D 1998/04/16
%V 51
%N 3
%P 213-218
%K 
%R https://doi.org/10.1071/C97154
%U https://www.publish.csiro.au/paper/C97154 
%X Cardinalic acid (1,7,8-trihydroxy-6-methoxy-3-methyl-9,10-dioxoanthracene-2-carboxylic acid) (4) and the known anthraquinone carboxylic acids endocrocin (1), dermolutein (2) and cinnalutein (3) have been isolated from the New Zealand toadstool Dermocybe cardinalis. Methyl 1,7,8-tri-O-methylcardinalate (5) has been prepared both by permethylation of the natural product (4) and from 2,6-dichloro-1,4-benzoquinone by two consecutive regioselective Diels&#8211;Alder cycloaddition reactions. A single-crystal X-ray structure analysis of the ester (5) corroborates the structure of the natural product (4) and confirms the outcome of both cycloaddition reactions. 
