Síntese de pirrolocumarinas via nitroestirenos e de novos selenetos derivados da cumarina

Abstract

This work describes the synthesis of pyrrolo[3,2-c]coumarins from 4-aminophenylcoumarins and nitrostyrenes (17 examples), which were obtained in yelds between 6 and 76 % in a reaction catalised by PTSA.H2O and under solvent-free conditions. These pyrrolocoumarins proved to be suitable substrates for further functionalization toward more complex polycyclic structures. A new derivative was synthesized by annulation reaction with diphenylacetylene and had eletrochemical and photophysical properties evaluated. Subsequently, novel selenocoumarins were prepared from diselenides and 4-tosylcoumarin (33 examples) in mild conditions and short reaction times. Products were obtained mostly in good yelds (22 to 85 %). Some selected examples of these novel selenides showed antioxidant properties on mice brain tissue.