| Abstract
| - An efficient and versatile strategy for the synthesis of nojirimycin C-glycosides and relatedcompounds with full stereocontrol is reported. The key steps of the process are the addition oforganometallic reagents onto an l-sorbose-derived imine (13) followed by an internal reductiveamination. The addition step, which controls the α- vs β-configuration at the pseudoanomeric centerin the final product, is highly diastereoselective (re-face addition), and the stereoselectivity can beeffectively inverted by adding an external monodentate Lewis acid (si-face addition). The completesynthesis could be achieved in 10 steps only from commercially available 2,3;4,6-di-O-isopropylidene-α-l-sorbofuranose and provided α- or β-1-C-substituted 1-deoxynojirimycin derivatives in 27−52%overall yield. The strategy was successfully extended to the first example of an iminosugar1-phosphonate. The methodology provides access to a wide range of biologically relevant glycoconjugate mimetics in which the glycosidic function is replaced by an imino-C-glycosidic linkage.
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