Galactopyranose 2-acetamido-2,6-dideoxy

Apart from L-fucose, 3-amino-3,6-dideoxy-D-galactose169 and the D (Ref. 170) and L (Ref. 171) enantiomers of 2-amino-2,6-dideoxygalac-tose (fucosamine) have been identified in bacterial LPS. 2-Acetamido-4-amino-2,4,6-trideoxy-D-galactopyranose has been isolated1710 from the capsular polysaccharide of Streptococcus pneumoniae. 

Methyl 5-acetamido-4,7,8,9-tetra-0-acetyl-3,5-dideoxy-D-g ycero-a.-D-galaclo-2-nonulopyranosylomte)-(2—>3)-2,4,6-tri-0-benzoyl-fi-D-galactopyranose (21)... 

To a solution of 2-(trimethylsilyl)ethyl CMmethyl 5-acetamido-4,7,8,9-tetra-0-acetyl-3,5-dideoxy-D-g/ycero-a-D-galacto-2-nonulopyranosylonate)-(2->3)-2,4,6-tri-0-benzoyl-P-D-galactopyranose (295 mg, 0.28 mmol) in 2 mL of dichloromethane was added trifluoro-acetic acid (2 mL) at 0°C, and the stirring was continued for 2 h at 0°C. Ethyl acetate (3 mL) and toluene (3 ml) were added and the solvents were evaporated. A second portion of toluene was added and the evaporation was repeated. Purification by flash chromatography on silica gel column with dichloromethane-methanol (20 1) gave the hemiacetal 21 (267 mg, quantitative) mp 85°C. 

Acetamido-2,4-dideoxy-4-fluoro-D-galactopyranose (38) and 2-acetamido-2,4,6-trideoxy-4,6-difluoro-D-galactopyranose (43) were synthesized from benzyl 2-acetamido-3,4-di-0-benzyl-2-deoxy-4-... 

N,N -Z) -ylc. 2-Acetamido-3-0-(3-aceta-mido-3,6-dideoxy-P-D-glucopyranosyl) -2-deoxy-D-galactopyranose [126247-65-2]... 

N-Ac 2-Acetamido-2,4-dideoxy-4-fluoro-D-galactopyranose C8H14FNO5 223.201 Tiny needles (EtOH/Et20). Mp 205-209° (195°). [a]o +87.7 (c, 1 in MeOH) (equilib.). Mixt. of anomers. 0,0,0f -Tetra-Ac 2-Acetamido-l,3,6-tri-0-acetyl-2,4-dideoxy-4-fluoro-D-galacto-pyranose... 

Acetamido-5-amino-2,5-dideoxy-L-idopyranose, D-441 2-Acetamido-4-C-(3-amino-2,2-dihydroxy-3-oxopropyl)-2,6-dideoxy-galactopyranose, S-33... 

Acetamido-2,3,4-tri-O-acetyl-5,6-dideoxy-p-D-allopyranose, A-366 2-Acetamido-l,3,6-tri-0-acetyl-2,4-dideoxy-4-fluoro-D-galactopyranose, A-372... 

Acetamido-l,2,3-tri-0-acetyl-4,6-dideoxy-p-D-galactopyranose, A-377 2-Acetamido-l,3,4-tri-0-acetyl-2,6-dideoxy-a-D-glucopyranose, A-380 2-Acetamido-l,3,4-tri-0-acetyl-2,6-dideoxy-p-D-glucopyranose, A-380... 

Acetamido-4-amino-2,4,6-trideoxy-D-galactose, D-473 4-Acetamido-4,6-dideoxy-D-galactopyranose, A-377... 

Selenium is excreted from the body mainly in the urine (approximately 60%). Major selenium compounds in the urine are trimethylselenonium ions and selenosugars, such as 1,2-dideoxy-l-methylseleno-2-acetamido-D-galactopyranose (6-38). Part of the selenium is excreted by the lungs in the form ofvolatile compounds such as dimethylselenide, dimethyldiselenide and selane. 

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