Efficient regioselective synthesis of triheterocyclic compounds: imidazo[2,1-b]benzothiazoles, pyrimido[2,1-b]benzothiazolones and pyrimido[2,1-b]benzothiazoles

Abstract

The preparation and characterisation of triheterocyclic compounds, via annulation reactions, are described. Amidines 1 reacted with substituted bromomethyl compounds, acid chlorides, and acrylic dienophiles to afford the corresponding imidazo[2,1-b]benzothiazoles 2 and pyrimido[2,1-b]benzothiazoles 3 or 4.