Synthesis of oxazolo[3,2‐b]hetero[1,2,4]thiadiazine S,S‐dioxides

Six bromomethyl derivatives of the new 2,3‐dihydrooxazolo3,2‐b]thieno3,4‐e]1,2,4]thiadiazine 5,5‐dioxides, 2,3‐dihydrooxazolo3,2‐b]thieno2,3‐e]1,2,4]thiadiazine 5,5‐dioxides and 6,7‐dihydrooxazolo‐3,2‐b]pyrazolo4,3‐e]1,2,4]thiadiazine 9,9‐dioxides heterocyclic ring systems were synthesized. These compounds are good intermediates for the preparation and development of promising antiviral and psy‐chotropic drugs. The structures of the products are supported by different nmr spectroscopic methods and mass spectrometry.