1,2,4,5-tetrazines as well as 1,2,4-triazines carrying sidechain dienophiles react in an intramolecular Diels-Alder cycloaddition with inverse electron demand to yield novel bicyclic pyridazines and pyridines.
                                    带有侧链亲二烯体的
1,2,4,5-四嗪以及
1,2,4-三嗪在分子内Diels-Alder环加成反应中产生反电子需求,从而生成新型双环
哒嗪和
吡啶。