REPLACEMENT REACTIONS IN THE QUINIC ACID SERIES

1963 ◽  
Vol 41 (10) ◽  
pp. 2417-2423 ◽  
Author(s):  
P. A. J. Gorin
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Acetic Acid ◽  
Magnetic Resonance ◽  
Quinic Acid ◽  
Mineral Acid ◽  
Aqueous Acetic Acid ◽  
Nuclear Magnetic

The action on D-quinic acid of hot 95% acetic acid containing mineral acid gave, after complete acetylation, 1,4,5-tri-O-acetyl-epi-quinide consisting of approximately equal portions of the (−)- and (±)-isomers, and tetra-O-acetyl-scyllo-quinic acid. The stereochemistry of the products and their derived free polyols were determined by nuclear magnetic resonance (n.m.r.) spectroscopy and synthesis.Elimination of the tosyloxy group in 5-tosyl-epi-quinicol was shown to take place readily in aqueous acetic acid with participation of the primary carbinol group to give an anhydro quinicol derivative and epi-quinicol.

1,4-DIMETHYLBICYCLO[2.2.1]HEPTANE DERIVATIVES

1965 ◽  
Vol 43 (8) ◽  
pp. 2306-2311
Author(s):  
Peter Yates ◽  
Thomas R. Lynch
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Acetic Acid ◽  
Sulfuric Acid ◽  
Magnetic Resonance ◽  
Methylmagnesium Iodide ◽  
Nuclear Magnetic Resonance Spectra ◽  
Magnetic Resonance Spectra ◽  
Nuclear Magnetic

The product from the action of methylmagnesium iodide on bicyclo[2.2.1]heptane-2,5-dione gave 2-exo-5-endo-diacetoxy-1,4-dimethylbicyclo[2.2.1]heptane on treatment with sulfuric acid in acetic acid. This has been converted to 1,4-dimethylbicyclo[2.2.1]heptane-2-exo-5-endo-diol, to 1,4-dimethylbicyclo[2.2.1]heptane-2,5-dione, and to 1,4-dimethylbicyclo[2.2.1]heptane-2-endo-5-endo-diol. The stereochemical assignments have been made on the basis of the interpretation of the nuclear magnetic resonance spectra of these compounds. The exo–endo diacetoxy compound is shown to be the expected product from a double Wagner–Meerwein rearrangement.

Unusual Nuclear Magnetic Resonance Dilution Shift for Acetic Acid in Acetic Anhydride

1963 ◽  
Vol 85 (14) ◽  
pp. 2173-2174 ◽  
Author(s):  
Norbert. Muller ◽  
Philip I. Rose
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Acetic Acid ◽  
Magnetic Resonance ◽  
Acetic Anhydride ◽  
Nuclear Magnetic

Structural analysis of the three lipopolysaccharides produced by Salmonella madelia (1,6,14,25)

1989 ◽  
Vol 67 (2-3) ◽  
pp. 78-85 ◽  
Author(s):  
José L. Di Fabio ◽  
Jean-Robert Brisson ◽  
Malcolm B. Perry
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Acetic Acid ◽  
Magnetic Resonance ◽  
Nitrous Acid ◽  
Periodate Oxidation ◽  
Ps Ii ◽  
Polysaccharide Fraction ◽  
Ps I ◽  
Hydrolysis Of ◽  
Nuclear Magnetic

Salmonella madelia reported to express the O-antigenic factors 1, 6, 14, and 25, defined in the Kauffmann–White classification system, was found to produce three different homogeneous lipopolysaccharides, which differed in having three structurally distinct O-polysaccharide components. The O-polysaccharide fraction obtained by mild acetic acid hydrolysis of the S. madelia lipopolysaccharide was analyzed by chemical composition, nitrous acid deamination, periodate oxidation, methylation, and 1H and 13C nuclear magnetic resonance methods and was demonstrated to be composed of three polysaccharides, PS(I), PS(II), and PS(III), which had the structures of repeating oligosaccharide units:[Formula: see text]Key words: Salmonella madelia, lipopolysaccharide, structure, analysis, nuclear magnetic resonance.

Carbon-13 nuclear magnetic resonance studies of (Z)-5-fluoro-2-methyl-1-{[p-(methylsulfinyl)phenyl] methylene}-1H-indene-3-acetic acid (sulindac) and some related compounds

1978 ◽  
Vol 56 (16) ◽  
pp. 2129-2133 ◽  
Author(s):  
Alan Wilmot Douglas
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Acetic Acid ◽  
Magnetic Resonance ◽  
Nuclear Spin ◽  
Substituent Effects ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Nuclear Magnetic Resonance Spectra ◽  
Spin Coupling Constants ◽  
Nuclear Magnetic

Carbon-13 nuclear magnetic resonance spectra have been obtained and fully assignee for a number of 2-methyl-1-{[p-(methylthio) or -(methylsulfinyl}phenyl]methylene}-1H-indene-3- acetic acid derivatives, including the potent anti-inflammatory compound sulindac, 1Z. Paired E and Z isomers were studied along with the sulindac sodium salt and ethyl ester in the Z series. Variations in steric crowding in E vs. Z isomers produce chemical shift effects which alternate with the number of intervening bonds. Fluorine substituent effects and 19F nuclear spin coupling to 13C nuclei, second-order features in off-resonance proton-decoupled spectra, and values of long-range 13CH nuclear spin coupling constants have been employed in making a complete set of assignments.

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