New xanthenodione: synthesis and antioxidant activity evaluation

6th Spanish-Portuguese-Japanese Organic Chemistry Symposium, Lisboa, de 18 a 20 de Julho de 2012 (Poster Communication).Due to the continuing interest of the research group in the synthesis of novel oxygen heterocycles we have recently developed a unique synthetic route towards new xanthenodiones 5 (scheme 1).[6] The application of this methodology in the cyclization of chromone derivatives 4b,c bearing methoxyl groups not only promote the cyclization to xanthenedione derivatives but also promote the demethylation leading to the 4-(benzylidene)-8-hydroxy-3-phenyl-3,4-dihydro-1H-xanthene-1,9(2H)-diones 5b,c . This interesting result prompted us to investigate the antioxidant potential of 4-(benzylidene)-8-hydroxy-3-phenyl-3,4-dihydro-1H-xanthene-1,9(2H)-diones 5a-c .Thanks are due to the University of Aveiro, Fundação para a Ciência e a Tecnologia (FCT) and FEDER for funding the Organic Chemistry Research Unit (project PEst-C/QUI/UI0062/2011) and the Portuguese National NMR Network (RNRMN)