The synthesis of chloroethylnitrososulfamide,(CENS), was carried out starting from chlorosulfonyl isocyanate, amines and haloalcohols through heterocyclization and decarboxylative reopening of N-sulfamoyl-2-oxazolidinones. A total regioselectivity concerning CO2 versus SO2 site hydrolysis was observed. A related aminolysis of sulfamoyloxazolidinones gave N-carbamoylsulfamides. The specific nitrosation on the N- ...