Synthesis of (1′S*,2R*,3R*)‐ and (1′s*,2r*,3s*)‐n‐arylsulfonyl‐2‐(1′‐halogenethyl)‐3‐methylindolines and Their Selective Toxicity Against SH‐SY5Y Cell Line

N‐tosyl‐2‐ and N‐tosyl‐4‐halogen‐substituted derivatives of 2‐(1‐methylbut‐2‐en‐1‐yl)aniline were synthesized and their molecular iodine‐mediated cyclization was investigated. The cyclization upon interaction of N‐tosyl‐6‐methyl‐2‐(1‐methylbut‐2‐en‐1‐yl)aniline with molecular iodine in methyl tert‐butyl ether or acetonitrile was studied, as well as the interaction of this sulfonamide with N‐bromosucinimide in dichloromethane. Synthesized (2R*,3R*)‐ and (2R*,3S*)‐N‐arylsulfonyl‐2‐(1‐halogenoethyl)‐3‐methylindoline derivatives showed cytotoxic activity against HEK293 cells, SH‐SY5Y, Jurkat, and HepG2 cell lines. The compounds (2R*,3S*)‐N‐arylsulfonyl‐7‐bromo‐2‐(1‐halogenoethyl)‐3‐methylindoline cis‐4a, stereoisomeric (2R*,3R*)‐trans‐4h and (2R*,3S*)‐N‐tosyl‐7‐chloro‐2‐(1‐halogenoethyl)‐3‐methylindoline cis‐4h demonstrated selective toxicity against SH‐SY5Y cell line (IC50 ≈ 3 ÷ 5 μM), and did not affect HEK293, Jurkat, and HepG2 cells.