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Selective Deprotonated Amide Activation of Dehydroalanine for Peptide Modification
Pengxin Wang1, Jinyuan Gong1, Yuntao Shi1
1State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
None:
Herein, we have discovered a unique deprotonated amide activation of dehydroalanine and developed a remote functionalization reaction of the double bond under mild conditions. The reaction exhibits good chemoselectivity and site-selectivity and is compatible with different kinds of peptides. Mechanistic studies first disclose in situ generated electron-rich enamine after deprotonation of amide hydrogen in Dha, followed by an intermolecular charge transfer process between the enamine and diaryliodonium salt.
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