Deptartment of Química Orgánica, Facultad de Química, Universidad de Sevilla, C/ Profesor García González 1, E-41012 Sevilla, Spain.
School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.
J Org Chem. 2020 Apr 3;85(7):5038-5047. doi: 10.1021/acs.joc.0c00324. Epub 2020 Mar 23.
The first examples of iminosugar-type 2-deoxy(thio)glycoside mimetics are reported. The key step is the activation of a bicyclic iminoglycal carbamate to generate a highly reactive acyliminium cation. Cerium(IV) ammonium nitrate efficiently promoted the formation of 2-deoxy -glycosides in the presence of thiols, probably by in situ generation of catalytic HNO, with complete α-stereoselectivity. Cooperative phosphoric acid/Schreiner's thiourea organocatalysis proved better suited for generating 2-deoxy -glycosides, significantly broadening the scope of the approach.
报道了首例亚氨基糖型 2-脱氧（硫）糖类似物。关键步骤是双环亚氨基糖氨基甲酸酯的活化，以生成高反应性的酰亚氨基阳离子。硝酸铈(IV)铵在硫醇的存在下有效地促进了 2-脱氧糖苷的形成，可能是通过原位生成催化 HNO，具有完全的α-立体选择性。协同磷酸/Schreiner 的硫脲有机催化更适合生成 2-脱氧糖苷，显著拓宽了该方法的范围。
