activated dimethylsulfoxide is reported herein. Although the yields of the reactions are moderate, this method enables the incorporation of the SCD3 group of dimethyl sulfoxide-d 6 into thiosulfonates. This is the first synthesis of deuterated thiosulfonates with a labeling purity above 99%. In addition, the cytotoxicity of the thiosulfonates is reported for the first time. thiols - esterification - sulfoxides