5-Methylisoxazole-3-carboxamide-Directed Palladium-Catalyzed γ-C(sp<sup>3</sup>)–H Acetoxylation and Application to the Synthesis of γ-Mercapto Amino Acids for Native Chemical Ligation
作者:Kalyan Kumar Pasunooti、Renliang Yang、Biplab Banerjee、Terence Yap、Chuan-Fa Liu
DOI:10.1021/acs.orglett.6b01160
日期:2016.6.3
Palladium-catalyzed acetoxylation of the primary γ-C(sp3)–H bonds in the aminoacids Val, Thr, and Ile was achieved using a newly discovered 5-methylisoxazole-3-carboxamide directing group. The γ-acetoxylated α-amino acid derivatives could be easily converted to γ-mercapto aminoacids, which are useful for native chemical ligation (NCL). The first application of NCL at isoleucine in the semisynthesis