Regiospecific O → N Acyl Migration as a Methodology to Access l-Altropyranosides with an N2,N4-Differentiation
Anna Niedzwiecka1, Quyen Pham1, Chang-Chun Ling1
1Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
Abstract:
Pseudaminic acid and its biosynthetic altropyranoside precursors are bacterial components currently being investigated toward novel antibacterial strategies. One structural feature associated with these naturally occurring flagellar carbohydrates is the different N-acylation patterns on the two amido functionalities, posing a synthetic challenge. A new one-pot methodology is reported and a scope of diverse N2/N4-differentiated analogs are presented via a Staudinger reduction-mediated regiospecific O3 → N4 acyl migration, followed by an autonomous N2-acylation.
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