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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Electrochemically promoted site-selective selenylation at the C-4 position of pyrazolones
Linyu Zheng1, Wei Zhong1, Zixun Gao1
1The National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine, Jiangxi University of Chinese Medicine 56 Yangming Road Jiangxi Nanchang 330006 P. R. China fengyulin2003@126.com 20211036@jxutcm.edu.cn.
Abstract:
The late-stage functionalization of drug molecules represents a significant advancement in medicinal chemistry. We herein describe an electrochemical strategy for site-selective selenylation at the C-4 position of pyrazolones under transition-metal- and oxidant-free conditions. This method exhibits broad substrate scope, accommodating a variety of pyrazolones and selenium sulfonates, and delivers the corresponding products in up to 92% yield. Using selenium sulfonates as selenylating reagents, this approach provides a practical route for introducing selenium into bioactive pyrazolone scaffolds, demonstrating considerable potential in drug diversification.
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