Survey on Methods of Preparation and Cyclization of Heterocycles

Abstract

This review covers some types of cyclic compounds represented by (mono-cycles, bi and multi-cycles, nomenclature, preparation methods, methods of cyclization, conditions of cyclization,). Cyclic compounds are considered that the nucleus of the basis in most of the biological compounds and pharmaceutical drugs due to their wide importance that comes from the contents of hetero- atoms due to their effects  and pharmacological effectiveness as antibiotics, A heterocyclic compound or ring structure is a cyclic compound that has hetero-atoms of at least two different elements as members of its rings. Heterocycles chemistry is the branch of chemical reaction in synthetic chemistry dealing with the synthesis, properties, with applications of these heterocycles 

Keywords: heterocyclic, cyclization, imidazole, tetrazole, pyrazole, thiadiazole, triazole, bicycles,

                        cumarine, indole.