Synthesis of Amino Sugars by Reduction of Hydrazine Derivatives; D- and L-Ribosamine, D-Lyxosamine^1-3

1H- and 13C-n.m.r. spectroscopy of synthetic monosulphated methyl α-d-galactopyranosides

“…analyses of sulphated oligosaccharides, and we now present the complete assignments of the 'H-(500 MHz) and i3C-(50 MHz)n.m.r. spectra of the sodium salts of methyl a-rr-galactopyranoside 2-, 3-, 4-, and 6-sulphate (5,9,12, and 13, respectively).…”

Steric and electrostatic interactions in reactions of carbohydrates. III. Direct displacment of the C-2 sulfonate of methyl 4,6-O-benzylidene-3-O-methyl-2-O-methylsulfonyl-.beta.-D-gluco- and -mannopyranosides

“…Elution with 98:2 benzene-2-propanol afforded two fractions. The first fraction (5 mg, 3.5%) could be the product of direct displacement, i.e., methyl 2-0-benzoyl-4,6-0benzylidene-3-O-methyl-a-D-mannopyranoside (15): ir (CHCI3) 1715 and 1265 cm-1 (C=0 and C-O stretch, benzoate); nmr (CDCI3) 8.2-7.2 (m, 10, two phenyl groups), 5.68 (s, 1, methine H from benzylidene group), 5.60 (unresolved m, 1, H-2), 4.85 (d, J 1,2 = 1.4 Hz, 1, H-l), 3.47 and 3.44 (two s, 6, C-l and C-3 methoxy groups). The second fraction (102 mg, 77.5%) was, according to ir and nmr spectra, the starting material 1.…”

“…Elution with 98:2 benzene-2-propanol gave slightly impure 15 (111 mg). The rechromatography on slica gel (16 g) and elution with 98:2 benzene-2-propanol afforded pure 15 (110 mg; 100%) as an amorphous solid: [a]27D -48°(c 1.0, CHCI3); ir (CHCI3) 1720 and 1265 cm-1 (C=0 and C-O stretch, benzoate); nmr (CDCI3) 5 8.2-7.2 (m, 10, phenyl), 5.68 (s, 1, methine H from benzylidene group), 5.61 (m, 1, H-2), 4.85 (d, J1>2 < 1 Hz, 1, H-l), 4.5-S.7 (m, 5, H-3, H-4, H-5, H-6, and H'-6), 3.46 and 3.43 (two s, 6, C-l and C-3 methoxy groups).…”

Synthesis of glycose carbamides and evaluation of the induction of erythroid differentiation of human erythroleukemic K562 cells

“…The synthesis of methyl α-and β-6-amino-6-deoxy-3,4-O-isopropylidene-D-galactopyranosides 15 and 16 was easily achieved starting from the corresponding anomeric diols 9 13 and 10 13 and employing the same reaction sequence. Reaction ofboth 9 and 10 with a slight excess of p-toluenesulphonyl choride caused the expected selective 14,15 tosylation of primary OH group. The resulting 6-sulphonates were subjected to nucleophilic displacement with NaN 3 , followed by reduction of resulting azides to furnish 15 and 16 in satisfactory overall yield (39 and 45%, respectively).…”