New multicomponent approach to polyfluoroalkylated pyrido[1,2-a]pyrimidine derivatives and bis-cyclohexenones

A one-pot three-component reactions between polyfluoroalkylated 3-oxo esters and methyl ketones with 1,3-diaminopropane result in 8-hydroxy-9a-alkyl(phenyl)-8-(polyfluoroalkyl)octahydro-6H-pyrido[1,2-a]pyrimidin-6-ones, whereas a similar reaction with 1,4-diaminobutane forms a salt with trifluoroacetoacetic ester. In a two-component reaction, diamines with a long aliphatic chain (1,4-diaminobutane, 1,6-diaminohexane and 1,8-diaminooctane) react with an aldol derived from trifluoroacetoacetic ester and acetone, to give bis-cyclohexenones having an aliphatic linker. Using 2-(aminomethyl)aniline in a three-component reaction with polyfluoroalkyl-3-oxo esters leads to new 7-hydroxy-5a-alkyl(phenyl)-7-(polyfluoroalkyl)-5a,6,7,8-tetrahydro-5H-pyrido[2,1-b]quinazolin-9(11H)-ones. Regioisomeric and spatial structures of new heterocycles were studied, and the mechanism of their formation was proposed. Some synthesized heterocycles were found to have moderate antiviral activity against influenza A/Puerto Rico/8/34 (H1N1) and Coxsackie B3 viruses.