Synthesis and antileukemic activity of spiro[indoline-3,2′-thiazolidine]-2,4′-diones

A number of spiroindoline-3,2′-thiazolidine]-2,4′-diones have been prepared via the cyclocondensation of isatin-3-imines with α-mercaptoacids. 1-Benzyl-5′,5′-dimethylspiroindoline-3,2′-thiazolidine]-2,4′-diones were prepared by simultaneously refluxing 1-benzylisatin, α-mercaptoisobutyric acid and various anilines in toluene. 3′-(4-Chlorophenyl)-5,5′-dimethylspiroindoline-3,2′-thiazolidine]-2,4′-dione was active in the P388 and the L1210 leukemia screen tests. A number of analogs of the active spiro compound have been prepared and submitted for antileukemic screening. Anticonvulsant screening results of related compounds are also included.