Treatment of sugar aldonitrones with dialkyl phosphites gave sugar α-deoxy-α-(N-hydroxy-N-methylamino)phosphonates, often highly stereoselectively. Repeated nucleophilic addition to a nitrone followed by oxidation of the resulting hydroxylamine allows the “first generation” nitrone, 1,2-O-isopropylidene-α-d-xylo-pentodialdo-1,4-furanose 5-(N-methyloxime), to be converted into the “third generation” cyclic nitrone, [(4R)-4-diethoxyphosphoryl-5H, 6H-1,3-oxazino][6,5-c](1,2-O-isopropylidene-α-d-xylo-tetrofuranose) N-oxide. The configurational and conformational assignments for all the new compounds prepared were based on short and long-range H,H, H,P, and P,C couplings, and new empirical rules regarding long-range H,P couplings are proposed. The sugar α-deoxy-α-hydroxyamino-phosphonates spontaneously oxidised in the air to give the corresponding nitroxide free-radicals, which afforded good e.s.r. spectra that allowed epimers at the α-carbon atom to be discriminated.