Review of Synthesis of Multispiro Heterocyclic Compounds from Isatin

Because of its various biological activities, isatin plays important roles in organic chemistry. The C-3 carbonyl group of the isatin possesses very high reactivity and thus isatin possesses many diverse applications in organic synthesis. This carbonyl group reacts like a prochiral center. For the organic synthetic chemist, the conception of a spiroheterocyclic building block has always been interesting, as it often requires synthetic design based on specific strategies. This review summarizes the synthesis of various multispiro heterocyclic compounds by using isatin through 1,3-dipolar cycloaddition reactions and multicomponent reactions.