Polymer-Supported Synthesis of Oligosaccharides Using a Diisopropylsiloxane Linker and Trichloroacetimidate Donors

10 páginas, 5 esquemasWe describe herein the polymer-supported synthesis of biologically relevant oligosaccharides using a diisopropylsiloxane linker and trichloroacetimidates as glycosyl donors. Siloxane linkers offer important advantages over closely related silyl ethers since even sterically hindered alcohols can be directly loaded onto commercially available polymers, such as soluble polyethylene glycol (PEG), without prior manipulation of the support. Final products can be easily detached by mild fluoridolysis to afford OH-tagged sugar probes. We followed an acceptor-bound approach that fixed the nucleophile on the polymer, and we selected soluble PEG as the support due to higher reactivity of bound sugars and easy reaction monitoring. Following this strategy, the trisaccharide repeating unit of the capsular polysaccharide of Neisseriameningitidis (serogroup L) and the disaccharide containing the structural motif of hyaluronic acid were successfully synthesized.We thank the Spanish Research Council (CSIC) (Grant 200880I041), the Spanish Ministry of Science and Innovation (Grants CTQ2006–01123 and CTQ2009–07168), Junta de Andalucía (Grant P07-FQM-02969, “Incentivo a Proyecto Internacional” and a fellowship to M. M. K.) and the European Union (FEDER support and Marie Curie Reintegration Grant) for financial support and Dr. Javier López-Prados and Ms. Sara López-Galán for technical assistance.Peer reviewe