Satoshi Okuda

Negative-ion fast atom bombardment tandem mass spectrometry for characterization of sulfated unsaturated disaccharides from heparin and heparan sulfate.

Negative-ion fast atom bombardment tandem mass spectrometry has been used in the characterization of non-, mono-, di- and trisulfated disaccharides from heparin and heparan sulfate. The positional isomers of the sulfate group of monosulfated disaccharides were distinguished from each other by negative-ion fast atom bombardment tandem mass spectra, which provide an easy way of identifying the positional isomers. This fast atom bombardment collision induced dissociation mass spectrometry/mass spectrometry technique was also applied successfully to the characterization of di- and trisulfated disaccharides.

Tandem mass spectrometry for characterization of unsaturated disaccharides from chondroitin sulfate, dermatan sulfate and hyaluronan

Fast atom bombardment tandem mass spectrometry has been used in the characterization of non-, mono-, di- and trisulfated disaccharides from chondriotin sulfate, dermatan sulfate and hyaluronan. The positional isomers of the sulfate group of mono- and disulfated disaccharides were distinguished from each other by both positive- and negative-ion fast atom bombardment tandem mass spectra, which gave sufficient information characteristic of the isomers. The anomeric isomers of nonsulfated disaccharides were characterized by the technique in the positive-ion mode. This fast atom bombardment collision induced dissociation mass spectrometry/mass spectrometry technique was also applied successfully to the characterization of trisulfated disaccharide.

Positive-ion fast atom bombardment tandem mass spectrometry for characterization of sulfated unsaturated disaccharides from heparin and heparan sulfate

Positive-ion fast atom bombardment tandem mass spectrometry has been used in the characterization of non-, mono-, di- and trisulfated disaccharides from heparin and heparan sulfate. The positional isomers of sulfate groups of monosulfated disaccharides have been distinguished from each other by positive-ion fast atom bombardment tandem mass spectra, which provide an easy way of identifying the positional isomers. The fast atom bombardment collision-induced dissociation mass spectrometry/mass spectrometry technique was also applied successfully to the characterization of di- and trisulfated disaccharides.

Ruthenium(II)-catalyzed [2 + 2 + 2] cycloaddition of 1,6-diynes with electron-deficient nitriles

Ru(II)-catalyzed cycloaddition of 1,6-diynes with electron-deficient nitriles gave the desired bicyclic pyridines in moderate to high yields.

The occurrence of uridine diphosphate N-acetylgalactosamine 6-sulfate in quail egg white and characteristic distribution of sulfated sugar nucleotides in different avian eggs

A sulfated sugar nucleotide has been isolated from quail egg white, and accounts for nearly 80% of the total sugar nucleotides found in the egg white. Evidence is presented that this nucleotide is uridine diphosphate N-acetylgalactosamine 6-sulfate, an isomer of the 4-sulfated derivative of uridine diphosphate N-acetylgalactosamine previously found in chicken egg white. Further studies on the distribution of sulfated sugar nucleotides in egg white of various birds (chicken, quail, pheasant, peafowl, turkey, goose, and duck) demonstrate that each species has a characteristic composition, differing from one another regarding the relative amounts of 4-sulfated, 6-sulfated, and 4,6-bissulfated derivatives of uridine diphosphate N-acetylgalactosamine.

Structure of 2-acetamido-3-amino-2,3-dideoxy-d-glucofuranurono-6,3-lactam

Abstract An X-ray crystallographic analysis of the title compound, an N-acetyl derivative of the 2,3-diamino-2,3-dideoxy- d -glucofuranurono-6,3-lactam found in the hydrolyzate of Pseudomonas aeruginosa P14 lipopolysaccharide, was performed. The crystals are monoclinic, space group P21, a = 11.704(2), b = 5.333(1), c = 7.399(2) A, β = 91.63(2)°, and Z = 2. The structure was solved by direct methods and refined by the block-diagonal least-squares method to a final R value of 0.046 for 796 independent reflections. The dihedral angle between the mean plane through the furanose ring and that through the γ-lactam ring is 106.2(2)°, the furanose ring is 1T2, and the C-3, C-4, C-6, and N-3 atoms of the γ-lactam ring are nearly coplanar. The conformation in aqueous solution is discussed, based on the 1H-n.m.r. data.