Journal ArticleDOI
A New Synthesis of Xanthones. 2,4,7‐Trichloronorlichexanthone and 4,5, 7‐Trichloronorlichexanthone, Two New Lichen Xanthones.
TLDR
A new synthetic route to norlichexanthone (1,3,6-trihydroxy-8-methyl- 9H-xanthen-9one) derivatives has been developed by using a Smiles rearrangement of an appropriately substituted depside in the key step as mentioned in this paper.Abstract:
A new synthetic route to norlichexanthone (1,3,6-trihydroxy-8-methyl- 9H-xanthen-9-one) derivatives has been developed by using a Smiles rearrangement of an appropriately substituted depside in the key step. 2,4,7-Trichloronorlichexanthone (22) and 4,5,7- trichloronorlichexanthone (29) have been prepared by this method. The former xanthone (22) was shown to be a constituent of the lichens Lecanora sulphurata and L. flavo-pallescens and the latter (29) a constituent of Micarea austroternaria var. isabellina.read more
Citations
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Pre-fractionated Microbial Samples – The Second Generation Natural Products Library at Wyeth
TL;DR: Wyeth has created a pre-fractionated natural products library using reversed-phase HPLC to complement their existing library of crude extracts and a cost-benefit analysis will be presented in this review.
Journal ArticleDOI
European taxa of saxicolous lecidella containing chloroxanthones: identification of patterns using thin layer chromatography
Ch. Leuckert,J.-G. Knoph +1 more
TL;DR: In this article, a method using TLC to recognize compound patterns consisting almost entirely of chloroxanthones in European saxicolous species of Lecidella is described, which is necessary for diagnosis of the taxa studied and of their chemotypes.
Journal ArticleDOI
Cytotoxic activity of orsellinates.
Alcir Teixeira Gomes,Neli Kika Honda,Fernanda Mesquita Roese,Rozanna Marques Muzzi,Leandro Sauer +4 more
TL;DR: Results showed that chain elongation - increase in lipophilicity (log P) - causes a rise in the cytotoxic activity of orsellinates, and the activities presented by 4-methoxy-ethyl orsellinate and ethyl orsellinated suggest that the hydroxy group at the C-4 position causes effect in theCytotoxic Activity of Orsellinates against Artemia salina.
Journal ArticleDOI
Lichen Metabolites Modulate Hydrogen Peroxide and Nitric Oxide in Mouse Macrophages
Iracilda Zeppone Carlos,Marcela B. Quilles,Camila Bernardes de Andrade Carli,Danielle Cardoso Geraldo Maia,Fernanda Paulin Benzatti,Thiago Inácio Barros Lopes,Aline S. Gianini,Rosenei L. Brum,Wagner Vilegas,Lourdes Campaner dos Santos,Neli Kika Honda +10 more
TL;DR: The results indicate that lichen products and their derivatives have potential immune-modulating activities and are likely to be useful in the treatment of infectious diseases.
References
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Journal ArticleDOI
A New Synthesis of Xanthones. 2,4,7-Trichloronorlichexanthone and 4,5,7-Trichloronorlichexanthone, Two New Lichen Xanthones
TL;DR: A new synthetic route to norlichexanthone (1,3,6-trihydroxy-8-methyl- 9H-xanthen-9one) derivatives has been developed by using a Smiles rearrangement of an appropriately substituted depside in the key step as discussed by the authors.
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