IJUP08 - Universidade do Porto

Synthesis of xanthone derivatives by microwave-assisted
methods
P. Vrbata 1 , M. Pinto 2,3 , R. Castanheiro 2,3 , S. Cravo 2,3
1 Department of Organic Chemistry, Faculty of Pharmacy, Charles University, Prague, Czech
Republic.
2 Department of Organic Chemistry, Faculty of Pharmacy, University of Porto, Portugal.
3 Research Centre of Organic Chemistry, Phytochemistry and Pharmacology of the University of Porto
(CEQOFFUP), Faculty of Pharmacy, University of Porto, Portugal.
Xanthone derivatives are very interesting compounds and our research group has a large
experience in synthesis of these bioactive derivatives by classic ways, generally with harsh
reaction conditions [1,2]. For that reason, it was performed reactions with microwave
(MW) irradiation or MW combined with adsorbed reactants onto a solid support such as
clays, in order to obtain new xanthone derivatives in a more environmentally friendly
manner, by performing higher-efficiency reactions using fewer and/or safer reagents.
So, in this work is described the synthesis of xanthonic building blocks 1 and 2 with MW
irradiation (Fig.1) and the dihydropyranoxanthones 3 and 4 (Fig.1) through a combined
method of MW with heterogeneous catalysis.
The structural elucidation of the compounds will be established by spectroscopic methods,
mass spectrometry, and additionally by X-ray crystallography.
The compounds 2-4 will be evaluated for biological activities, namely antitumor activity in
human cancer cell lines.
Fig.1. Synthesized xanthonic derivatives.
References:
[1] Pinto, M.M.M., Sousa, M.E. and Nascimento, M.S.J. (2005), Xanthone Derivatives: New
Insights in Biological Activity, Current Medicinal Chemistry, 12 (21), 2517-2538.
[2] Pinto, M.M.M. and Sousa, M.E. (2005), Synthesis of Xanthones: An Overview, Current
Medicinal Chemistry, 12 (21), 2447-2479.
Acknowledgments: FCT (I&D, nº226/94), FEDER, POCI, U. Porto, and Caixa Geral de Depósitos
for financial support.
166