Nitrosochloroethyldimethylurea , its cas register number is 59960-30-4. It also can be called 1-Nitroso-1-(2-chloroethyl)-3,3-dimethylurea ; BRN 2255038 ; and Urea, 1-(2-chloroethyl)-3,3-dimethyl-1-nitroso- .