Design, synthesis and biological evaluation of 3-fluoroalkenyloxindole ring-fused 3-trifluoromethyloxindoles obtained from indoline-2,3-diones and difluoromethylene phosphabetaine

A wide variety of multi-substituted 3-fluoroalkenyloxindole ring-fused 3-trifluoromethyloxindoles were obtained in good yields by the reaction of indoline-2,3-diones with difluoromethylene phosphabetaine. Their biological activities against human prostate cancer cells PC-3 and human Breast cancer cells MCF-7 have been preliminarily demonstrated, using MTT-based assays with the commercially available standard drug Paclitaxel as a positive control. Several compounds exhibited comparable in vitro inhibitory activities against human prostate cancer cells PC-3 and human Breast cancer cells MCF-7 to Paclitaxel. These results indicate that 3-fluoroalkenyloxindole ring-fused 3-trifluoromethyloxindoles may be potential lead compounds for further biological screening.