Synthesis of 1,3-disubstitue-2,3-dihydro-1H-naft[1,3]oxazine compounds

Development of novel synthetic methods for the construction of new analogs of bioactive heterocyclic compounds represents a major challenge in synthetic organic and medicinal chemistry. Investigation of the substituted 1,3-oxazine compounds has shown that they possess varied biological properties such as analgesic, anticonvulsant, antitubercular, antibacterial and anticancer activity. The tautomeric character of 1,3-O, N heterocycles offers a great number of synthetic possibilities, eg. they can be used as intermediates in the synthesis of N-substituted amino alcohols or nitrogen-bridged heterocyclic systems.Betti?s classical procedure, a Mannich-type aminoalkylation reaction of 2-naphthol, was applied to prepare the starting materials for the synthesis of the present target compounds.Condensation of 2-naphthol and aryl- and hetarylaldehydes in the presence of ammonia gave 1,3-disubstitued-2,3-dihydro-1H-naftoxazines.The structures of the obtained new compounds have been clarified by spectroscopic methods (FTIR, 1H NMR, 13C NMR and MASS) after the purification processes.