Structure-activity relationships of 3-substituted-5,5- -diphenylhydantoins as potential antiproliferative and antimicrobial agents

A series of twelve 3-substituted-5,5-diphenylhydantoins was synthe- sized, including some whose anticonvulsant activities have already been re- ported in the literature. Their antiproliferative activities against HCT-116 hu- man colon carcinoma cells were evaluated to determine structure-activity relationships. Almost all of the compounds exhibited statistically significant antiproliferative effects at a concentration of 100 μM, while the derivative bearing a benzyl group was active even at lower concentrations. Moreover, their in vitro antibacterial activities against Escherichia coli ATCC 25922, Sta- phylococcus aureus ATCC 25923 and clinical isolates of Escherichia coli, Pro- teus mirabilis, Pseudomonas aeruginosa, Enterococcus faecalis and Staphylo- coccus aureus were evaluated. Only the 3-isopropyl and 3-benzyl derivatives showed weak antibacterial activities against the Gram-positive bacterium E. faecalis and the Gram-negative bacteria E. coli ATCC 25922 and E. coli.