Hetero-Diels-Alder Reaction of 3-Bromo-7-(bromomethyl)tetracyclo[5.3.1.02,6.04,8]undec-10(12)-ene-9,11-dione with Pentafulvenes: Facile Synthesis of Novel Polycyclic Cage Compounds Having a Pyran Ring - James, Beena; Suresh, E; Nair, Mangalam S (Synlett, 2006)