TFA derivatives on separate runs (see Table II).Structural Assignment with Respect to Stereoisomers. Immediately following the main fraction of the wine sample, two smaller fractions were eluted which were also present in synthetic 2 derived from a mixture of the diastereomeric 2,3-butanediols. Mass spectra for the three components differed in their abundances at m/e 55, 73, 126, and 182 (see Table II). GC-MS analysis of 4,5-dimethyl-l,3-dioxolane-2-propanamine TFA, 2a, which was synthesized by using essentially pure D(-)-2,3-butanediol, gave only the first (main) fraction. It can therefore be concluded that the main fraction of 4,5-dimethyl-l,3-dioxolane-2-propanamine in wine is an acetal of threo-2,3butanediol and that the two minor fractions are acetals of erythro-(meso-) 2,3-butanediol. Stevens (1969) reported the presence of both 2,4,5-trimethyldioxolane and 2,4-dimethyl-5-ethyldioxolane in wine. Muller et al. (1979) also identified a number of cyclic acetals in sherry. This and the present work suggest that cyclic acetals of other aldehydes may be present in wine. ACKNOWLEDGMENT Grateful acknowledgment is given to William Haddon and Sandra Tillin of the Western Regional Research Laboratories of the U.S. Department of Agriculture, Albany, CA, for the Cl and exact mass work.
SUMMARY
The fulvic acid and alkali‐soluble polysaccharide fractions of a sandy loam arable soil of the Countesswells series have been subjected to acid hydrolysis or methylation and the products examined by infra‐red and NMR spectroscopy, pyrolysis mass spectrometry and chemical analysis. Infra‐red and NMR spectroscopy of the polysaccharide fraction indicated that the substance was predominantly carbohydrate, although sugars accounted for less than one‐third of the weight by chemical analysis. Pyrolysis mass spectrometry con‐firmed the presence of sugars by sugar anhydride formation, but also showed the presence of ‘secondary’ or ‘pseudo’ polysaccharide. The fulvic acid contained only 2–3% sugars by chemical analysis, whereas a much larger carbohydrate component was suggested by physicochemical analyses. Infra‐red and pyrolysis mass spectrometry difference spectra for the residues after acid hydrolysis indicated the release of material with some of the characteristics of glycoprotein. Most of the carbohydrate present in the fulvic acid was of the secondary or pseudo polysaccharide type. The hypothesis that the secondary polysaccharide could be a degraded polysaccharide structure in which some sugar residues have been partly transformed to melanoidins by Maillard reaction is explored.
2 mm i.d. glass column packed with 3% OV-101 on 80/ 100-mesh Supelcoport (Supelco Co.). The air, hydrogen, the high-dose treatment. A dose-related difference showed the majority of the urinary metabolites were recovered as conjugated products under the high-dose treatment.A significant sex-related metabolic difference was observed under the low-dose treatment. A majority of the urinary metabolites from the female rats were conjugated products, 30% of the administered dose, compared to the 5% observed in the male rats. A similar sex-related difference was also observed in the whole blood residue/time plot, which showed the contribution of biliary recirculation in the disposition of cinmethylin in the female test animals.
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