DMPU
N,''N''′-Dimethylpropyleneurea is a cyclic urea sometimes used as a polar, aprotic organic solvent. Along with the dimethylethyleneurea, it was introduced as an analog of tetramethylurea.
In 1985, Dieter Seebach showed that it is possible to replace the suspected carcinogen hexamethylphosphoramide with DMPU.