Synthesis of 3-Aminopyrido[2,1-a]isoquinolin-4-one Derivatives via Condensation of Azlactones with 1-Alkyl-3,4-dihydroisoquinolines

Abstract

Reactions of available 1-alkyl-3,4-dihydroisoquinolines with 4-(2,2,2-trifluoroacetyl)-, 4-acetyl- or 4-(ethoxy-methylene)-2-aryloxazol-5(4H)-ones were studied. A series of new 3-amino-6,7-dihydro-4H-pyrido[2,1-a]isoquinolin-4-one derivatives was synthesized. The intermediates formed as a result of the addition of azlactone to 1-methyl-3,4-dihydroisoquinoline were isolated. The effect of the nature of the substituents, as well as the reaction conditions on the yield and structure of the title products was revealed.