https://doi.org/10.1351/goldbook.A00367
A @[email protected] involving fusion of a new ring to a molecule via two new bonds. Some authors use the term '@[email protected]' for the fusion of an additional ring to an already existing one, and 'annulation' for the formation of a ring from one or several acyclic precursors, but this distinction is not made generally.
See also:
cyclization