Microwave irradiation provided unique chemical processes with special attributes as enhanced reaction rates, higher yields, greater selectivity. We are developing in the synthesis of fused pyridine ring by means of the thermal electrocyclic reaction of aza 6π-electron system incorporating one double bond of the aromatic or heteroaromatic moiety. We here describe the construction of isoquinoline framework based on the microwave assisted thermal electrocyclic reaction of 1-azahexatriene system involving the benzene 1,2-bond, and its applications to the synthesis of trispheridine (phenanthridine alkaloid) and 6-deoxybostrycoidin (azaanthraquinone alkaloid).
