This article reviews the ring-opening reaction of five-membered nitrogen-containing heterocyclic compounds. Heterocyclic compounds are more and more important in organic synthesis, and five-membered nitrogen-containing heterocycles are the most important part of them. Their ring-opening reactions can be used for preparing polyfunctional or other cyclic compounds. They can serve as the key reaction in protecting groups, chemistry and biomimetic syntheses.

Key words: NITROGEN HETEROCYCLICS, FIVE MEMBER RING HETEROCYCLIC COMPOUNDS, ORGANIC SYNTHESIS, RING CLEAVAGE REACTION, PROTECTIVE GROUP