2H-1,3,2-Oxazaphosphorin-2-amine, 4,4'-dioxybis[N,N-bis(2-chloroethyl)tetrahydro-, 2,2'-dioxide 4-Hydroxycyclophosphamide anhydro-dimer 4-Peroxycyclophosphamide 51274-71-6 NSC 176986 NSC176986