Etymology Borrowed from New Latin annulatus, from Latin ānulātus.
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Chemistry, Natural sciences, Physical sciences To cause (something) to undergo an annulation reaction (a reaction which forms a ring of atoms).
A conceptually different approach was undertaken by Schreiber and coworkers in which, rather than annulating the enediyne bridge onto a cyclohexane-type precursor, both rings were assembled in a single transformation, specifically an intramolecular Diels-Alder reaction (Scheme XII) (30).1995, Donald B. Borders, Terrence W. Doyle, editors, Enediyne Antibiotics as Antitumor Agents, New York, N.Y. […]: Marcel Dekker, Inc., →ISBN, page 393: