3- Ethyl-2-methyl-477-pyrido pyrimidin-4-thione

Ethyl-2-methyl-4//-pyrido[l,2-a]pyrimidin-4-thione was obtained in... 

Alkylation of l-aryl-4-cyano-l-trifluoromethyl-2,3-dihydro-lH-pyrido [l,2-c]pyrimidine-3-thiones with benzyl bromides, ethyl 2-broroacetate, and 2-chloroacetamides in the presence of K2C03 in DMF at ambient temperature gave 3-[(substituted methyl)thio)]-lH-pyrido[l,2-c]pyrimi-dines in 51-87% yields (07MI1). 

The 3-imino group of 4-cyano-2-ethyl-3-imino-2,3,5,6,7,8-hexahydro-l//-pyrido[l,2-c]pyrimidine-l-thione was acylated with phenyl isocyanate (78MI1). The imino group of l-imino-4-cyano-3-methylthio-l//-pyrido[l,2-cjpyrimidine was alkylated and acylated with methyl iodide and acetic anhydride (75YZ13). Reaction of 3-amino-4-phenyl-4-[2-(A, N-di-n-pro-pylamino)ethyl-4,4 a,5,6,7,8-hexahydro-l //-pyrido[l, 2-c ]pyri midin-l-one with acetic anhydride in pyridine and with sodium nitrite in aqueous acetic acid afforded 3-acetamido and perhydro-l,3-dioxo derivatives, respectively (87USP4680295). 

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