N.m.r. studies of d-ribosylamines in solution: Derivatives of hydroxylamine,hydrazine, thiosemicarbazide,and secondary amines

N.m.r. spectroscopic studies (¹H, ¹³C) have shown that hydroxylamine and hydrazine react with 2,3-O-isopropylidene-d-ribofuranose (1) and d-ribose (2) to give primarily the acyclic oxime and hydrazone, respectively, whereas thiosemicarbazide affords mainly the cyclic pyranosyl and furanosyl derivatives. Acyclic or cyclic secondary amines, when condensed with either 1 or 2, furnished only mixtures of the β-pyranosyl and β-furansyl forms, and, in some reactions, Amadori rearrangement products (2–30%).