the 30th Anniversary of Mizutani Foundation for Glycoscience

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without the previously required thermal equilibration (Figure 5). Further exploration into this chemical space will allow for a unique opportunity to synthesize fully β-linked oligosaccharides at cryogenic temperatures. Figure 4. One-flask synthesis of oligosaccharidesstarting sugar. This approach is applicable to the synthesis of oligosaccharides, 2-deoxyaminoglycosides, and unprotected carbohydrates. Ongoing studies using conformationally-flipped 2-deoxythioglycosides show that β-reactivity is achievable ReferencesFigure 5. Intial result in conformationally β-glycosylations 1) Krasnova, L.; Wong, C.-H. "Oligosaccharide Synthesis and Translational Innovation." J. Am. Chem. Soc. 2019, 141, 3735. 2) Hoang, K. M.; Lees, N. R.; Herzon, S. B. "Programmable Synthesis of 2-Deoxyglycosides." J. Am. Chem. Soc. 2019, 141, 8098. 3) Kaneko, M.; Herzon, S. B. "Scope and Limitations of 2-Deoxy- and 2,6-Dideoxyglycosyl Bromides as Donors for the Synthesis of β-2-Deoxy- and β-2,6- 4) Rychnovsky, S. D.; Mickus, D. E. "Preparation of 2-lithiotetrahydropyrans: Kinetic and thermodynamic generation of alkyllithium reagents." 5) Cohen, T.; Matz, J. R. "A general preparative method for α-lithioethers and its application to a concise, practical synthesis of brevicomin." J. Am. Chem. 6) Kyasa, S.; Meier, R. N.; Pardini, R. A.; Truttmann, T. K.; Kuwata, K. T.; Dussault, P. H. "Synthesis of Ethers via Reaction of Carbanions and 7) Baryal Kedar, N.; Zhu, D.; Li, X.; Zhu, J. "Umpolung Reactivity in the Stereoselective Synthesis of S‐Linked 2‐Deoxyglycosides." Angew. Chem., Int. Ed. 8) Hoang, K. M.; Lees, N. R.; Herzon, S. B. "General Method for the Synthesis of α- or β-Deoxyaminoglycosides Bearing Basic Nitrogen." J. Am. Chem. Soc. 9) Elshahawi, S. I.; Shaaban, K. A.; Kharel, M. K.; Thorson, J. S. "A Comprehensive Review of Glycosylated Bacterial Natural Products." Chem. Soc. Rev. Dideoxyglycosides." Org. Lett. 2014, 16, 2776.Tetrahedron Lett. 1989, 30, 3011.Soc. 1980, 102, 6900.Monoperoxyacetals." J. Org. Chem. 2015, 80, 12100.2013, 52, 8012.2021, 143, 2777.2015, 44, 7591.10) Bai, Y.; Shen, X.; Li, Y.; Dai, M. "Total Synthesis of (−)-Spinosyn A via Carbonylative Macrolactonization." J. Am. Chem. Soc. 2016, 138, 10838.105