Es wird die Kondensation mehrerer vollacylierter 1-Halogen-zucker mit dem Quecksilber(I1)-acetat-Komplex 4 des 4(5)-Nitro-imidazols in unpolaren Losungsmitteln beschrieben. Die Reinigung gelingt auf der Stufe der geschiitzten Nucleoside 5a-15a durch Saulen-oder praparative Schichtchromatographie. Die Struktur und Konfiguration der freien 4-Nitro-imidazolnucleoside 5b-15b wird mit Hilfe von UV-, IR-und 1H-NMR-Spektren bestimmt. Die Hydrierung von 5b, 6b und 8b liefert die 4-Amino-Derivate 5c, 6c und 8c. Imidazole Nucleosides, I. -Nucleosides of 4(5)-Nitro-and 4(5)-AminoirnidazoleThe condensation of some acylglycosyl halides with the mercuric(I1) acetate complex 4 of 4(5)-nitroimidazole in unpolar solvents is reported. The protected nucleosides 5a-15a can be purified by column or preparative layer chromatography. The structures and configurations of the unprotected 4-nitroimidazole nucleosides 5 b-15b are determined by UV-, IR-and NMR-spectra. Hydrogenation of 5b, 6b, and 8b yields the 4-amino derivatives 5c, 6c, and 8c.

It is demonstrated that the 220—225 nm Cotton effect of 4-nitro imidazole nucleosides can be used for the determination of the configuration of this class of compounds. A more detailed picture about conformation and configuration of the sugar residue is received from the copperammonia complexes of these nucleosides.The pH-dependency of the stability and the complex ratio are discussed for a furanose moiety. Correlation between signs and intensities of the Cotton effects and configurations and conformations of the diol structures are discussed.

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Durch Umsetzung des Glucopyranosylbromids (I) mit dem Nitroimidazol‐ Hg(II)‐Komplex (II) in Toluol wird das β‐Nucleosid (III) erhalten, das durch Ammonolyse zu (IV) desacetyliert wird.