OBTAINING DIHYDROTHIENO[3,2-d]PYRIMIDINES AND INTERMEDIATE PRODUCTS, APPLIED FOR THEIR SYNTHESIS Russian patent published in 2014 - IPC C07D495/04 C07D333/40 

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of obtaining compounds of formula . The compounds of formula 6 are intermediate products for obtaining dihydrothieno[3,2-d]pyrimidines, which produce an impact on the cardiovascular system, possess sedative action, or can be applied in treatment of inflammatory diseases of joints, skin, eyes or diseases of the peripheral or central nervous system, respiratory or gastrointestinal disorders. The method includes the following stages: a) interaction of reagents of formulas HS-CH₂-CO₂R^a and CHR⁵=CR⁴-CO₂R^a with obtaining an intermediate product of formula ; and b) cyclisation of the intermediate product of formula 7 in a solvent in the presence of TiCl₂(O-iPr)₂, TiCl(O-iPr)₃, TiCl₃(O-iPr) and in the presence of a base-amine, with obtaining a product of formula 6. R^a stands for alkyl, R⁴ and R⁵ are independently selected from a group, including H, C₁-C₆-alkyl, C₂-C₆-alkenyl, C₂-C₆-alkinyl, C₆-C₁₀-aryl, C₆-C₁₀-aryl-C₁-C₆-alkylene, C₅-C₁₀-heteroaryl-C₁-C₆-alkylene, C₃-C₁₀-heterocycle and C₅-C₁₀-heteroaryl, -O-C₁-C₆-alkyl, -O-C₆-C₁₀-aryl, -O-C₃-C₁₀-heterocycle and -O-C₅-C₁₀-heteroaryl, -NR'R", fluorine, C₁-C₆-fluoroalkyl and C₁-C₆-fluoroalkoxygroup, where R' and R" are independently selected from a group, including H and C₁-C₆-alkyl, and where in each case the group can be optionally substituted with one or more groups, selected from a group, including OH, oxogroup, halogen, C₁-C₆-alkyl and O-C₁-C₆-alkyl. The method makes it possible to obtain the intermediate products 6, which do not require carrying out distillation and chromatographic purification between stages in realisation of processes suitable for wide-scale synthesis of dihydrothieno[3,2-d]pyrimidines.

EFFECT: invention results in higher total output of the final products as compared to that in realisation of methods of preceding level of technology.

6 cl