Nitrogen and oxygen-linked heterocyclic compounds have received considerable attention due to their wide applications. Hence, development of new methods based on green chemistry protocol for the synthesis of new aza and oxo heterocyclic compounds are very important.
In the first part of this thesis, an efficient method based on green chemistry protocol for the synthesis of novel pyridopyrimidine derivatives has been reported from the condensation reaction between heterocyclic nitroketene aminals, malononitrile derivatives and aromatic aldehydes under catalyst-free and solvent- free condition at 90 oC.
In another part of this research, by using a one-pot, four-component reaction between isatin derivatives, isatoic anhydride, malononitrile and ?-dicarbonyl compounds, an efficient and green method for the synthesis of novel spiro- pyranotryptanthrin has been reported by using DABCO as catalyst in acetonitrile as solvent under reflux conditions.