De Novo Construction of Chiral Aminoindolines by Cu-Catalyzed Asymmetric Cyclization and Subsequent Discovery of an Unexpected Sulfonyl Migration

• Published in: Journal of the American Chemical Society Vol. 144; no. 43; pp. 19932 - 19941
• Main Authors: Wang, Bao-Cheng, Fan, Tingting, Xiong, Fen-Ya, Chen, Peng, Fang, Kai-Xin, Tan, Ying, Lu, Liang-Qiu, Xiao, Wen-Jing
• Format: Journal Article
• Language: English
• Published: American Chemical Society 02.11.2022
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.2c08090

Searching for efficient strategies to access structurally novel aminoindolines is of great significance for drug discovery. However, catalytic asymmetric de novo construction of aminoindoline scaffolds with functionality primed for diversification still remains elusive. Here, we report a Cu-catalyzed asymmetric cyclization of ethynyl benzoxazinones with amines, producing chiral 3-aminoindolines in good yield and with high enantioselectivity (up to 97% yield and 98:2 er). Moreover, a radical-mediated sulfonyl migration of these products was unexpectedly found, further affording new chiral 3-aminoindolines bearing alkenyl sulfonyl groups with retained enantiopurity (up to 84% yield and 98:2 er). Bioactivity evaluations indicate that these 3-aminoindolines show notable antitumor activities and chirality is proven to have a significant impact on their antitumor activity.