scholarly journals Nuclear Magnetic Resonance Spectroscopy of Amino-sugars. III. Substitutional and Configurational Effects of Amino Group and Related Functions on the Chemical Shift and Coupling Constant in Deuterium Oxide

1966 ◽  
Vol 14 (11) ◽  
pp. 1210-1219 ◽  
Author(s):  
Shigeharu Inouye
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Deuterium Oxide ◽  
Resonance Spectroscopy ◽  
Amino Sugars ◽  
Amino Group ◽  
Coupling Constant

scholarly journals Carbon-13 nuclear-magnetic-resonance spectroscopy of Forssman hapten

1981 ◽  
Vol 195 (3) ◽  
pp. 529-533 ◽  
Author(s):  
T A W Koerner ◽  
L W Cary ◽  
S C Li ◽  
Y T Li
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Intestinal Mucosa ◽  
Fatty Acyl ◽  
Resonance Spectroscopy ◽  
Chemical Shift Assignments ◽  
Amide Linkage

The 13C n.m.r. spectrum of Forssman hapten was obtained at 25.16 MHz in [3H] chloroform/[2H] methanol (1:1, v/v), using purified glycosphinogolipid from canine intestinal mucosa (glycolipid I). All amide, olefin, anomeric, intersaccharide glycosidic ether, amide linkage, methyl and many methylene resonances were resolved and assigned. Analysis of the anomeric region reveals the following pentaglycosylceramide structure as originally proposed [Siddiqui & Hakomori (1971) J. Biol. Chem. 246, 5766-5769]: GalNAc (alpha 1 leads to 3) GalNAc (beta 1 leads to 3) Gal (alpha 1 leads to 4) Gal (beta 1 leads to 1) ceramide. Analysis of the amide, olefin and methylene regions reveals no alpha-hydroxy fatty acyl group and less than or equal to 6 mol% unsaturated fatty acyl groups are present. Chemical-shift assignments are reported for the anomeric and glycosidic ether carbon atoms of intersaccharide-linked alpha-galactose and N-acetyl-alpha-galactosamine residues. Two rules are proposed for the assignment of the anomeric form of 1 leads to 3 and 1 leads to 4 linkages of galactose and N-acetylgalactosamine residues present in the glycone of glyco-conjugates. The present study emphasizes the importance of the anomeric “window” (80-120 p.p.m.) in studies of glycone structure.

The characterization of primary, secondary, and tertiary vanadate alkyl esters by 51V nuclear magnetic resonance spectroscopy

1988 ◽  
Vol 66 (10) ◽  
pp. 2570-2574 ◽  
Author(s):  
Alan S. Tracey ◽  
Michael J. Gresser
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Chemical Shifts ◽  
Hydroxyl Group ◽  
Resonance Spectroscopy ◽  
Low Field ◽  
Nuclear Magnetic

A variety of alkyl vanadates has been studied by 51V nuclear magnetic resonance spectroscopy. It was found that the equilibrium constant for condensation of vanadate with alcohols is insensitive to whether the hydroxyl group is primary, secondary, or tertiary. These products, however, have characteristic vanadium chemical shifts that allow assignment of nmr signals to the appropriate ester. It was also found that chemical shifts are additive in the sense that the chemical shifts of the esters ROVO3H− are one half the chemical shift of the diesters (RO)2VO2− when those shifts are given relative to −559 ppm. This effect is independent of whether the signals are to high or low field of −559 ppm and the additivity extends to mixed ligand systems. This value of −559 ppm is close but not equal to the chemical shift of the vanadate monoanion, H2VO41−, which is at −561 ppm. These results are at variance with arguments concerning the effects of ligand bulkiness on chemical shifts of vanadium(V) complexes.

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