Carbohydrates carbon

Arya DP (2006) Diazo and Diazonium DNA Cleavage Agents Studies on Model Systems and Natural Product Mechanisms of Action. 2 129-152 El Ashry ESH, El KUany Y, Nahas NM (2007) Manipulation of Carbohydrate Carbon Atoms for the Synthesis of Heterocycles. 7 1-30 El Ashry ESH, see El Nemr A (2007) 7 249-285... 

On the other hand, resonance assignments for CP of threonine and serine, and C and Cy of hydroxy proline, were difficult to make, because of their proximity to carbohydrate carbon resonances. In most cases then, the resonances were assigned on the basis of the effects of pH on the chemical shifts of those resonances. It was shown that the chemical shifts for the carbohydrate carbon resonances were virtually unaffected (AS 0.4 p.p.m.) when going from the cationic state (pH 2) to the anionic state (pH 11) of the amino acid residues. The chemical shifts of C and CP of the amino acid residues, however, shifted considerably (up to 3.1 and 6.6 p.p.m. for C" and CP, respectively see Table VI). 

C-2-0-2 bonds.7 45 The assignments of the carbohydrate-carbon resonances of Arap model compounds (61, 62) were based on comparisons with the 13C chemical-shift data for methyl a- and / -arabinopyrano-side.89-110... 

L. Hough, J. E. Priddle, and R. S. Theobald, Carbohydrate carbonates. Part II. Their preparation by ester-exchange methods, J. Chem. Soc. (1962) 1934-1938. 

Humic acid is composed of aromatic, aliphatic and carbohydrate carbon compounds. An average humic acid s elemental composition is 55.1% C, 5.0% H, 3.5% N, 35.6% O, and 1.8% S (Rice and MacCarthy, 1991). Its molecular weight distribution is typically broad, and it is a relatively high-molecular-weight material relative to the fulvic acid isolated from the same soil or sediment. It s predominantly functionalized by carboxylic acid and phenolic groups. At least some components of humic acid are surface-active, and these components have been shown to form micelles in concentrated, alkaline aqueous solutions (Piret et al., 1960 Visser, 1964 Wershaw et al., 1969 Tschapek and Wasowski, 1976 Chen et al., 1978 Rochus and Sipos, 1978 Hayano et al., 1982 Hayase and Tsubota, 1984 Guetzloff and Rice, 1994). 

Soil- and sediment-derived fulvic acid is also composed of aromatic, aliphatic, and carbohydrate carbon components, though it is generally believed to be more aromatic than the humic acid from that same environment. A typical fulvic acid s elemental composition is 46.2% C, 4.9% H, 2.5% N, 45.6% O, and 1.2% S (Rice and MacCarthy, 1991). The carboxyl group is the predominant functional group in... 

From this preliminary review of monosaccharide glycosides, it is possible to see that the fragmentation pattern in FAB mass spectra is governed by at least three factors whose importance may vary (1) nature of the aglycone, (2) configuration of the anomeric carbon (3) remote stereochemical effects (i.e., the relative stereochemistry of the other carbohydrate carbons). 

Total organic carbon minus biochemicals (lipids, protein, and carbohydrates) carbon. 

Dissolved carbohydrate carbon concentrations in microlayer and subsurface samples from non-slicked areas, after Sieburth et al. (1976)... 

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