SYNTHESIS OF 6,7-DIHYDRO-5H-THIOPYRANO2,3-dPYRIMIDIN-5-ONE DERIVATIVES STARTING WITH 4,6-DICHLORO-2-(METHYLSULFANYL)PYRIMIDINE

摘要

An efficient synthesis of 7-substituted 6,7-dihydro-5H-thiopyrano2,3-dlpyrimidin-5-one derivatives from readily available 4,6-dichloro-2-(methylsulfanyl)pyrimidine (DCSMP) has been developed. Thus, this starting material is converted to the corresponding 1-(4-chloro-6-methoxy(or dialkylamino)pyrimidin-5-yl)alk-2-en-1-ones by using easily operational sequences. These enones are then treated with sodium hydrogensulfide under mild conditions to afford the desired products in satisfactory yields.