LAUSR

Recently, the researchers have synthesized a series of heterocyclic compounds which are derivatives of oxazoles, thiazoles, imidazoles, pyridines, pyrimidines, benzimidazoles, benzothiazoles [1-6]. Such an interest in these heterocycles is caused by their rather high biological activity. The solution of heterocycles and heterocyclic systems synthesis problems is a wider use of electrophilic intramolecular cyclization reactions [7, 8]. This is favored by the search for new variants of this reaction with still insufficiently studied functional groups of unsaturated compounds and the involvement of new electrophilic reagents. Recently, special attention is paid by the researchers to the reactions of electrophilic intramolecular heterocyclization of alkenyland alkynylsubstituted heterocycles [9-11]. The development of the synthesis methods for pyrimidine-based heterocyclic systems via its alkenyl derivatives intramolecular cyclization is of practical importance. The use of the latest techniques allows to obtain a range of compounds that are interesting in structure and properties and which can both be directly used and serve as synthetic blocks for more complex structures [12-14].