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The 1H and 13C NMR spectroscopy was used to study the structure of previously unknown aldose series condensation products (L-fucose, L-rhamnose, D-mannose, D-galactose, D-glucose, N-acetyl-D-glucosamine, N-acetyl-D-mannosamine, D-lactose and D-maltose) with 6-mercapto-hexanoic acid hydrazide—promising glycoligands of noble metal nanoparticles. It was shown that L-fucose, L-rhamnose, D-mannose, D-galactose and N-acetyl-D-mannosamine derivatives exist in solution in DMSO-d6 as a tautomeric mixture of open hydrazone and cyclic pyranose forms. The linear hydrazone form is represented by a set of Z′,E′-conformational isomers, which differ in the arrangement of substituents relative to the C–N amide bond in comparable amounts. The condensation products obtained on the basis of D-glucose, N-acetyl-D-glucosamine, D-lactose and D-maltose in the crystalline state and in solutions in DMSO-d6 have an exclusively cyclic pyranose structure represented by α,β-configurational isomers. A similar transition to the pyranose form is observed in solutions of all the studied compounds in D2O. [ABSTRACT FROM AUTHOR]