164120-27-8 7-beta-(2-N-(2-Chloroethyl-N-nitroso-N-carbonyl)amino(hydroxymethyl)ethyl)cholesterol Urea, N-(2-chloroethyl)-N'-(3-hydroxy-2-((3-beta,7-beta)-3-hydroxycholest-5-en-7-yl)propyl)-N-nitroso-