Synthesis of Polyhydroxy-2,3-diarylxanthones with potencial antioxidant activity

Xanthones are a well-studied class of heterocyclic compounds [1] and over the years these substances have been extensively studied due to their biological properties. Both natural and synthetic derivatives have shown important anti-microbial, anti-tumour, anti-inflammatory as well as antioxidant act...

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Detalhes bibliográficos
Autor principal: Santos, Clementina M.M. (author)
Outros Autores: Silva, Artur (author), Cavaleiro, José (author)
Formato: conferenceObject
Idioma:eng
Publicado em: 2011
Texto completo:http://hdl.handle.net/10198/3426
País:Portugal
Oai:oai:bibliotecadigital.ipb.pt:10198/3426
Descrição
Resumo:Xanthones are a well-studied class of heterocyclic compounds [1] and over the years these substances have been extensively studied due to their biological properties. Both natural and synthetic derivatives have shown important anti-microbial, anti-tumour, anti-inflammatory as well as antioxidant activities [2]. Several structure/activity studies of polyphenolic compounds revealed that the presence of hydroxyl substituents in certain positions of their skeleton is of great importance for a high antioxidant activity [3]. Taking this knowledge into consideration, we report the synthesis of new polyhydroxy-2,3- diarylxanthones, starting from the 3-bromo-2-methylchromone 1. Aldol condensation of 1 with benzaldehydes leads to the formation of 3-bromo-2-styrylchromones 2 followed by Heck reaction with styrenes to give the 2,3-arylxanthones 3 [4]. The final step consists in the cleavage of protective groups to obtain the desired polyhydroxy-2,3-diarylxanthones 4