3-methoxy-1,3,5(10)-estratriene-17(R)-spiro-6'-(2'-(bis-(2-chloroethyl)amino)-2'-oxo-1'-oxa-3'-aza-2'-phosphorane)
3-methoxy-1,3,5(10)-estratriene-17(r)-spiro-6'-(2'-(bis-(2-chloroethyl)amino)-2'-oxo-1'-oxa-3'-aza-2'-phosphorane)