On the Intramolecular 1,4-Dipolar Cycloaddition Reaction of Thiazinium Betaines for the Construction of Aza-, Diaza-, and Polyaza-Heterocyclic Ring Systems - Padwa, Albert; Coats, Steven J; Harring, Scott R; Hadjiarapoglou, Lazaros; Semones, Mark A (Synthesis, 1995)