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Four new phenylphenalenone pigments have been isolated from Anigozanthos rufus Labill. and their structures have been determined. The known compound 2-phenylnaphthalic anhydride was also isolated from the plant. The synthesis of one of the new pigments, and of some related compounds, is described.

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Two new pigments, haemofluorone A and haemofluorone B, have been isolated from the flowers of Macropidia fuliginosa Drum. and also from the root system of Phlebocarya ciliata R.Br. Spectroscopic analysis indicates the structures 5,8,9- and 8,9,11-trihydroxy-lH-naphtho[2,1,8-mna]xanthen-l-one. The former structure has been confirmed by a synthesis of the trimethyl ether by photochemical oxidative cyclization of 9-(3,4-dimethoxyphenyl)-6-hydroxy-2-methoxy-1H-phenalen-1-one.The parent chromophore, 1H-naphtho[2,1,8-mnalxanthen-1-one, and the 2,5-dimethoxy derivative have also been prepared by analogous photochemical reactions of the appropriate arylphenalenones.

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