Abordagem para a síntese de amidas naturais bioativas e seus análogos

Abstract

The results described in this thesis are part of a research project which aims at the syntheses of molecules with potential antiparasitic activity using natural products as precursors. The stereoselective syntheses of nine (E,E)-dienamides with different substitution patterns, which are analogous to natural piperine (isolated from Piper nigrum) were carried out. The synthetic approach involves, as a key step, an EmmonsHorner reaction of the piperidinylphosphonoacetamide anion with suitable aldehydes, which were in turn prepared from the natural allylbenzenes, safrole and eugenol. This synthetic methodology was further employed in the syntheses of the natural amides piperine, piperettine and 3,4-methylenedioxicynamamide, which are all found in the Piper genus. The new amides will be investigated in relation to their potential action against epimastigote forms of the protozoan Trypanosoma cruzi, the ethiological agent of the Chagas disease