We report a facile two-step procedure that allows the synthesis of the title fused heterocyclic derivatives from 4-chloro-6-methoxy-2-(methylsulfanyl)pyrimidine, readily available from 4,6-dichloro-2-(methylsulfanyl)pyrimidine (DCSMP). The first step is the lithiation at the 5-position of the starting material with lithium diisopropylamide (LDA) and the reaction of the resulting lithium compound with a-keto esters to give the corresponding 2-hydroxy-2-(pyrimidin-5-yl)carboxylic acid ester derivatives. In the second step, these are treated with primary aliphatic amines in the presence of triethylamine to afford the desired products.
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