Intramolecular cyclization of N-aryl amides for the synthesis of 3-amino oxindoles
Haitao Yang1, Yu Pan1, Yijing Tian1
1Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Key Laboratory of Research and Development for Natural Products, Yunnan Characteristic Plant Extraction Laboratory, School of Pharmacy, Yunnan University, Kunming, 650500, P. R. China. zhanghb@ynu.edu.cn.
Abstract:
A mild and efficient strategy to synthesize pharmaceutically important 3-amino oxindoles from readily available N-aryl amides has been developed. This unique reaction proceeds via the intramolecular cyclization of 2-azaallyl anions with N-aryl amides to afford 3-amino substituted oxindoles. This novel method avoids the direct usage of transition metal catalysts and additional oxidants. Furthermore, the anti-pulmonary fibrosis activity evaluation showed that 3-amino oxindole 2f significantly inhibited collagen deposition, which can ameliorate pulmonary fibrosis by reducing excessive extracellular matrix (ECM) deposition.
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