Reaction of 1,3‐Diethyl‐4,5‐dihydroxyimidazolidin‐2‐one with 1,3‐Dimethylsulfamide at a High Pressure.

The title reaction under conditions of a solvent phase transition was found to afford N-(1,3-diethyl-5-hydroxy-2-oxo-4-imidazoli-dinyl)-N,N'-dimethylsulfamide along with expected 2,4-dimethyl-6,8-diethyl-3-thia-2,4,6,8-tetraazabicyclo[3.3.0]octan-7-one 3,3-dioxide.