Synthesis of pyridopyrimidine derivatives based on benzenesulfonyl acetonitrile compounds via a one-pot sequential four-component domino reaction and microwave-mediated molecular cyclization

A concise, rapid and highly efficient method for the one-pot synthesis of novel pyridopyrimidine derivatives has been demonstrated by the “four-component” domino reaction of aromatic aldehyde, benzenesulfonyl acetonitrile, 1,1-dimethylthio-2-nitroethylene and 1,3-propanediamine, using piperidine as a catalyst and ethanol as solvent under microwave irradiation. This methodology was established with many advantages, including higher reaction yields, broad substrate scopes, experimental simplicity, short time and utility of easily available starting materials. The synthesized compounds are confirmed by ¹H NMR, IR and HR-ESI-MS.