Background: Spirooxindoles are privileged scaffolds in medicinal chemistry, which were identified
through Wang’s pioneering work as inhibitors of MDM2-p53 interactions.
Objective: To design and synthesize 2,6-diarylidenecyclohexanones and dispiro[oxindole-cyclohexanone]-
pyrrolidines having potential antitumor effect.
Methods: Dispiro[oxindole-cyclohexanone]-pyrrolidines 6a-h were synthesized in a regioselective manner via
1,3-dipolar cycloaddition reaction of 2,6-diarylidenecyclohexanones 3a-h, isatin, and sarcocine. Compounds
6a-h were alkylated to give (7-10)a,b. All compounds were evaluated in vitro for their antitumor activity and
cytotoxic selectivity against breast cancer cell lines (MCF-7 and MDA-MB-231), breast fibrosis cell line
(MCF10a), and placental cancer cell line (JEG-3). Molecular modeling inside the MDM2 binding site was performed
Results: Synthesized compounds showed antitumor activity comparable to tamoxifen and compounds 3a,b,f,g
and 9a,b showed selective cytotoxicity against tumor cells but reduced toxicity toward MCF-10a cells. Molecular
modelling shows that both classes of synthesized compounds are predicted to fit the deep hydrophobic cleft
on the surface of MDM2 and mimic the interactions between p53 and MDM2.
Conclusion: The synthesized compounds have antitumor activity against MCF-7, MDA-MB-231, and JEG-3.
Few compounds showed a selective cytotoxic effect and may have the potential to inhibit MDM2 and stimulate
p53. In the future, studies regarding the optimization of medicinal chemistry as well as mechanistic studies will
be conducted to enhance the inhibition effect of identified compounds and elucidate their mechanism of action.