Solid‐Phase Synthesis of 1,3,5,6‐Tetra‐Substituted 3,5‐Dihydroimidazo[4,5‐c][1,2]Thiazin‐4(1H)‐One 2,2‐Dioxide Derivatives

The synthesis of 1,3,5,6‐tetra‐substituted 3,5‐dihydroimidazo[4,5‐ c ][1,2]thiazin‐4(1 H )‐one 2,2‐dioxide derivatives was optimized through solid‐phase synthesis. Synthetic strategies such as Merrifield resin, Thorpe‐Ziegler reaction, Mitsunobu reaction, intramolecular cyclization, and desulfonative nucleophilic substitution were employed to synthesize a total of 31 derivatives. The synthesis showed high yields of 72%–87% per step over 8 steps, resulting in an overall yield of 7%–33%, thereby developing an efficient synthetic route for the derivatives.