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An efficient chemical synthesis of carboxylate-isostere analogs of daptomycin
Sabesan Yoganathan1, Ning Yin, Yong He
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA.
Abstract:
Herein we report a direct and efficient method for the synthesis of four new carboxylate-isostere analogs of daptomycin. The side chain carboxylic acid moieties of the aspartic acids (Asp-3, Asp-7 and Asp-9) and β-methyl glutamic acid (MeGlu-12) were all converted into the corresponding carboxylate isosteres using direct synthetic procedures. The present study also describes an esterification protocol to overcome the possible backbone cyclization of the activated side chain carboxylic acid group of either Asp or Glu onto the backbone amide.
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