Synthèse et Application des Nouveaux Hétérocycles

Abstract

Nitrogen heterocycles are present in many natural products with biological activities. In this work we considered two new synthetic approaches for the heterocyclic pyrido [2,3-d] pyrimidine motif under mild conditions. A study of the molecular fluorescence of these products with respect to the variation of the solvent and the concentration was performed. This work is divided into two main parts: The first part of this work describes the two new routes for the synthesis of pyrido [2,3-d] pyrimidines. The first route is based on the nucleophilic attack of primary amines (hydrazine) on the synthesized formamidines which allowed us to synthesize this family with very good yields. The second route is based on the use of 2- aminopyridine as a precursor for the synthesis of pyrido [2,3-d] pyrimidines in a "one pot" process with three components without solvent under microwave or the use of a catalyst. The second part of this work deals with the study of the fluorescence of four compounds prepared during this work. This study is based on the influence of certain factors such as the concentration and the nature of the solvent used on the intensity of the molecular fluorescence.