Regioselective Reactions, Spectroscopic Characterization, and Cytotoxic Evaluation of Spiro‐pyrrolidine Thiophene

Spiro‐oxo‐indole/pyrrolidine‐thiophene base possessed significant pharmacological activity. The [3 + 2] cycloaddition reactions of thia‐methine ylide respected through multi‐component reaction affording regioselective and stereoselective spiroindoline‐3,2′‐tetrahydrothiophene derivative 3 . Reaction of such compound with different electrophilic and nucleophilic reagents afforded bioactive heterocyclic compounds 4 – 16 . Biological evaluation showed that these synthesized spiro‐pyrrolidine exhibited moderate to good cytotoxic activity. Among them, compounds 7 and 14 displayed the best cytotoxic activity against MCF‐7 and Wl‐38 cells with the IC 50 values of 7.02 ± 0.6 and 8.97 ± 0.9 μm (very strong), respectively. Compounds 4 , 5 , and 12 exhibited strong cytotoxicity's with IC 50 16.28 ± 1.7, 11.16 ± 1.1, and 19.14 ± 1.7 μm, respectively, against MCF‐7 mammary gland cell line. All compound structures were supported by spectroscopic data and elemental analysis.