The title compound, C6H6N4O2S, was prepared for structural comparison with
diazoxide (7-chloro-3-methyl-4H-1,2,4-benzothiadiazine 1,1-dioxide) and oth
er 3-alkylaminopyridothiadiazine 1,1-dioxides known to be potassium channel
openers. Particular attention was paid to the tautomeric conformation adop
ted by the compound in the crystalline state, which is found to be the 4H-f
orm.