Crystal structure and solid-state ~(13)C NMR analysis of N-p-nitrophenyl-alpha-D-ribopyranosylamine,N-p-nitrophenyl-alpha-D-xylopyranosylamine,and solid-state ~(13)C NMR analysis of N-p-nitrophenyl-2,3,4-tri-O-acetyl-beta-D-lyxopyranosylamine and N-p

摘要

The X-ray diffraction analysis of N-p-nitrophenyl-alpha-D-ribopyranosylamine (1) and N-p-nitrophenyl-alpha-D-xylopyranosyl-amine (2) was performed.It was found that an independent part of the unit cell of compound 1 is formed by three molecules of sugar whereas the crystals of compound 2 have one molecule in the independent part of the crystal unit cell.Additionally,1 crystallizes with one molecule of water.The solvent molecule forms an extensive hydrogen bond network with the hydroxyl groups of the sugar,and this efficiently stabilizes the crystal lattice.Contrary to 2,the sugar moieties of 1 adopt the ~1C_4 conformation.In the spectra of 2,N-p-nitrophenyl-2,3,4-tri-O-acetyl-beta-D-lyxopyranosylamine and N-p-nitrophenyl-2,3,4-tri-O-acetyl-alpha-L-arabinopyr-anosylamine the number of resonances does not exceed the number of carbon atoms in the molecules,thus indicating no polymorphism.In the spectrum of (1) the signals are split,confirming the presence of three independent molecules in the crystal unit cell.