example 3 are represented below additional studies will demonstrate that compounds of the instant invention have a large therapeutic window by sparing normal cells such as fibroblasts and keratocytes but killing tumors cells such as ej cells and hct116 cells studies will also demonstrate that dna in normal cells remains unaffected by compounds of the instant invention and that there is no increase in ros in normal cells fig1 4 show in vivo efficacy of the compounds against pancreatic cancers cells breast epithelium and ej bladder cancer cells we tested the anti tumor effect sp2007 and sp83 in bladder tumor xenograft bearing mice four nude nude mice weighing approximately 0 02 kg were fasted overnight and anestatized with avertin 2 2 2 tribromoethanol 250 mg kg body weight 1p injection a total 2 u00d7 106 ej cells acquired from japanese cellbank were implanted subcutaneously on opposite site flanks in each of four nude nude mice in each treatment group mice were fed and given water ad lib when tumor masses grew to approximately 2 to 5 mm in diameter control vehicle sp2007 or sp83 were administered intraperitoneally total 2 mg kg every 24 hours for 25 days anti tumor effects were observed in sp2007 and sp83 administered tumor mice as compared to control dmso administered tumor mice results are shown in fig5 although this invention has been described with a certain degree of particularity it is to be understood that the present disclosure has been made only by way of illustration and that numerous changes in the details of construction.