1,3-Dipolar cycloaddition reactions of homochiral cyclic nitrones derived from 1-deoxynojirimycin

An Efficient Synthesis of Aldohexose-Derived Piperidine Nitrones: Precursors of Piperidine Iminosugars

“…The structures of the two nitrones have been determined undoubtedly by NMR and NOESY experiments (see Supplementary Materials ). It is worth noting that the d -glucopyranose-derived piperidine nitrone 7 was found to be quite stable, even at room temperature, rather than unstable as has been reported before [ 84 ], while the l -idopyranose-derived piperidine nitrone 17 is less stable, and gradually decomposed at room temperature, although it was stable at low temperature when stored in a fridge.…”

“…Although, methods for the synthesis of cyclic nitrones have been well documented [ 66 ], including oxidation of hydroxylamine [ 67 , 68 , 69 ], amines [ 70 , 71 , 72 , 73 ], and imines [ 74 , 75 ], condensation of ketones with hydroxylamines [ 76 , 77 ], and N -alkylation of oximes [ 78 , 79 , 80 ], efficient synthetic methods for the preparation of pyranose-derived nitrones are still lacking. Several syntheses of pentopyranose-derived piperidine nitrones have been reported before [ 81 , 82 , 83 ], however, to the best of our knowledge, the only synthesis of a hexopyranose-derived piperidine nitrone so far has been reported in 1996 by van den Broek and co-workers [ 84 ] who described the preparation of pyranose-derived nitrones by oxidation of 2,3,4,6- O -benzyl-DNJ 6 employing 2,2-dimethydioxirane (DMDO) as oxidizing agent ( Scheme 1 ). This method, however, has obvious drawbacks in that the regioselectivity of the oxidation was poor and the oxidation of the piperidine resulted in the formation of an inseparable mixture of two regio-isomers, i.e.…”

Synthesis of anL-Fucose-Derived Cyclic Nitrone and its Conversion toα-L-Fucosidase Inhibitors

“…Their restricted use is surprising in view of the versatile character of nitrones and of their potential for the preparation of carbohydrate-derived heterocycles. Presumably, the restricted application is related to the difficulties of preparing such cyclic nitrones in a regioselective manner [7] [12].…”

Exploring the Metal‐Catalyzed Reactions of α‐Diazo‐β‐hydroxyamino Esters: Conversion of Cyclic Aldonitrones into Ketonitrones

“…We have disclosed a new, efficient method for the synthesis of cyclic ketonitrones based on a 1,2‐hydride shift in carbenoids derived from α‐diazo β‐hydroxyamino esters. Although cyclic aldonitrones have often been prepared and used in synthesis, cyclic ketonitrones have been less studied . This approach for their efficient two‐step synthesis from aldonitrones should help foster the development of new synthetic applications of this class of nitrones.…”