[Novel Bis-sulfonic Acid Esters with Cytostatic Activity (author's transl)]

The introduction of electron-withdrawing groups into the group R of piposulfan analogs R--SO2--O--X--O--SO2--R substantially increases their antileukemic activity in animal tests (leukemia L 1210). The central moiety X can be varied considerably (provided it contains amide groups) without appreciable loss of activity. A number of busulfan analogs as well as busulfan itself proved to be practically inactive against murine leukemia L 1210. Among a total of 122 bis-sulfonic acid esters tested 35 gave a survival time index of 150% or more after i.p. application and 5 after oral application.