Reductive Cyclization of δ-Hydroxy Nitriles:  A New Synthesis of Glycosylamines

Abstract

[reaction: see text] The stereoselective cyclization of delta-hydroxy nitriles to afford N,O-acetals and the application of this reaction toward the synthesis of glycosylamines is described.

New Uses for the Burgess Reagent in Chemical Synthesis: Methods for the Facile and Stereoselective Formation of Sulfamidates, Glycosylamines, and Sulfamides

“…[22] While relatively simple ideas based on our previous success in reacting 1,2-diol substrates, their success would be of considerable value, since glycosylamines have proven to be exceedingly difficult to synthesize. Indeed, available methods based on the use of glycosyl azides, glycals, [23] Kochetkov aminations, [24] and a-hydroxy nitriles, [25] among others, typically lack substrate generality and often result in variable stereoselectivity, especially in complex contexts. In addition, none of these methods singularly provides a means to obtain both a-and b-anomers at will and in a controlled manner.…”

Neighboring‐Group Participation in Nitrile‐Forming Beckmann Fragmentation Reactions: Synthesis of Enantiopure (E)‐2,3‐Di‐O‐substituted‐5‐methoxy‐ pent‐4‐enenitriles and Their Conversion into Pyranosylamines

“…In both cases, reductive cyclization resulted in the preferential formation of the β anomer, as previously reported for these reactions. [18] However, it is worth noting that in the case of compounds 19, the β configuration means an axial orientation, as shown by the 13 C NMR analysis of the C1 atom shielded at around 77 ppm. [18] This sequence thus allows a simple approach to a library of stereodefined pyranosylamines.…”

“…[18] The reductive cyclization of hydroxynitriles to provide glycosylamines is a known reaction. [28,29] However, owing to the biological activity of this class of cyclic N,O-acetals, glycosylamines are a central motif in N-linked glycopeptides and glycoproteins,…”

“…Here we describe some of our results in the development of a method in which regio-and stereocontrolled bond fragmentation of densely functionalised ketoximes occurs to give enantiopure functionalised pentanenitrile derivatives, which are valuable as precursors in the synthesis of biologically active compounds, such as glycosylamines, [18] 1-β-amino-1-deoxynojirimycins [19,20] and -glucoamidines.…”

The iodosulfonamidation of peracetylated glycals revisited: access to 1,2-di-nitrogenated sugars

“…5 Anomeric azides are particularly wellsuited for these purposes: they are easily prepared from glycosyl halide or hydrazide precursors, 6 are more stable than anomeric amines and readily react in Cu I -catalysed Huisgen azide-alkyne 1,3-dipolar cycloadditions. 7-9 When the parent 2-amino-2-deoxy sugar is accessible, anomeric amines/amides can also be prepared from glycosyl azides, 10 a-hydroxy nitriles, 11 isonitriles, 12 or by simple straightforward amination. 13 Otherwise, 1,2-di-nitrogenated compounds can be accessed either through a combination of one among the above mentioned strategies and one method of preparation of 2-aminosugars 14 or through specific approaches.…”