Site-Selective Acylations of α- and β-Hydroxyamides in Complex Molecules: Application of Template-Driven Acylation to
Yasuhiro Nishikawa1, Shione Toda1, Takami Matsui1
1Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, Aichi 468-8503, Japan.
Abstract:
Site-selective acylations of α-and β-hydroxyamides in complex polyols are described. The combination of a pyridine aldoxime ester and Zn(OTf)2 facilitates the acylation of two types of N-glycolyl disaccharides, namely, Gal-GlcNGc and Neu5Gc-Gal, both of which are partial structures of polysaccharides responsible for biological actions, with highly site-selective modifications achieved. Furthermore, biotinylation, one of the most important techniques in chemical biology, is used to site-selectively acylate the β-hydroxyl group in a glycopeptide.
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