RESUMO
Compounds 1-6 and 11 representing key members of the marinoquinoline family of natural products, together with the related marine alkaloid aplidiopsamine A (12), have been synthesized using various combinations of palladium-catalyzed Ullmann cross-coupling and reductive cyclization processes involving a C3-arylated pyrrole as the common intermediate. These natural products have been characterized by single-crystal X-ray analyses and evaluated as inhibitors of acetylcholinesterase (AChE) with congener 2 proving to be the most active.
RESUMO
This article describes the use of Amberlite IRA-910 with different counter ions as excellent polymer-supported reagents in nucleophilic substitution reactions. The versatility of this protocol allowed the synthesis of a diversified library of phenacyl derivatives with high yields. The polymeric reagents can be reloaded several times with no loss of their efficiency.
Assuntos
Acetofenonas/síntese química , Cetonas/química , Resinas Sintéticas/química , Tiocianatos/química , Acetofenonas/química , Compostos de Bromo/síntese química , Compostos de Bromo/químicaRESUMO
In this study, an efficient method was designed to graft poly(ethylene glycol) effectively onto commercial Dowex resin. The catalytic efficiency of the copolymer obtained as a new solid-liquid phase transfer catalyst was studied. It was proved that this organocatalyst is an efficient heterogeneous catalyst for regioselective azidolysis of epoxide in water and gave azidohydrin in excellent yield under mild reaction conditions. The polymeric catalyst was easily recovered by simple filtration and showed no appreciable loss of activity when recycled several times.