Colouring Matters of Australian Plants. XXI. Naphthoxanthenones in the Haemodoraceae

Abstract

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.

Phenylphenalenones and related natural products from Wachendorfia thyrsiflora L.

“…Based on the above NMR data and combined with MS data (see Section 4), the structure of compound 21 was elucidated as 2,4-dihydroxy-9-(3,4-dihydroxyphenyl)-1H-phenalen-1-one. The other seven known compounds were determined by 1 H NMR and/or 2D NMR spectroscopy, mass spectrometry, and comparison with reported data as thyrsiflorin (1) (Dora et al, 1991), haemofluorone B (22) (Cooke and Dagley, 1979), anigorufone (10), hydroxyanigorufone (23), dihydroxyanigorufone (24) (Cooke and Thomas, 1975), 4-hydroxyanigorufone (25), and anigorootin (6) (Hö lscher and Schneider, 1999).…”

HPLC-NMR and HPLC-MS Profiling and Bioassay-Guided Identification of Secondary Metabolites from the Australian Plant Haemodorum spicatum

“…2,17,[27][28][29]39,40 Off-line isolation and subsequent characterization of peak D (Figure 1) confirmed this component to be the new phenylphenalenone haemoxiphidone (8), which was isolated as an orange solid. This particular compound was concurrently isolated within the research group from a separate Haemodorum species.…”

“…However, two reports have suggested that oxidative cyclization may be involved in converting phenylphenalenones to oxabenzochrysenones. 27,28 As part of continuing efforts to study the chemical diversity and ethnopharmacology of Australian plants, particularly of the family Haemodoraceae, the chemistry of Haemodorum spicatum R. Br. was investigated.…”

9-Aryl-phenalenones: Bioinspired thermally reversible photochromic compounds for photoswitching applications in the pico-to milliseconds range

“…[25][26][27][28] 9PPNs produce reactive oxygen species when exposed to UV and blue light [29][30][31][32] and produce secondary metabolites capable of absorbing light at longer wavelengths (Scheme 1 bottom). [33][34][35][36][37] The structural similarity between these metabolites and the NXs produced in the cyclization of 9PPNS, suggests a common mechanism of production. A major difference is the superior stability of the natural counterparts conferred by the rearomatization of the NX form by hydroxy-oxo tautomerization.…”