Polyols and sugars

D-fructose (13) undergoes photochemically induced catalytic oxidation by 0 to D-erythrose (14) and other fragments in the presence 

The reaction occurs via photochemically induced oxidation by the metal ion and reoxidation of the reduced metal ion by O.  

Ascorbic acid, an enediol, undergoes facile oxidation with 0 in 

The oxidation of saturated diols is of interest due to its relevance to lignin oxidation. Catalysts based on iron porphyrins have been described. A free-radical cleavage via an oxoiron(IV) intermediate has been proposed. 

Blackburn, N.J., J. Chem. Soc., Dalton Trans., 534 Blackburn, N.J., J. Chem. Soc., Dalton Trans., 1596 

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Concentrated aqueous salt solutions were used for dehydration of carbohydrates catalyzed by RuCh + Ag2S04 ( RUSO4 ) [47]. Such solvents may also help in constracting aqueous-organic biphasic media with good phase separation properties. Selective dehydroxylation of polyols and sugars was achieved in aqueous solutions with the use of anionic rathenium carbonyls, as well [48]. 

Since the stereochemical outcome of LiAfflLj reduction of isoxazolines is predictable according to the parameters described above (140,293), this concept was exploited in efficient syntheses of various amino polyols and sugars as represented... 

Y Shimazu, M Uehara, M Watanabe. Simultaneous determination of ethyl alcohol, polyols, and sugars in grape must and wine by high-performance liquid chromatography. J Brew Soc Japan 75(4) 327-331, 1980. 

Synthesis of compatible solutes and production of stress-tolerant plants The cellular response of salt- and drought-tolerant organisms to both long- and short-term sah-nity stresses includes the synthesis and accumulation of a class of osmoprotective compounds known as compatible solutes. These relatively small, organic osmolytes include amino acids and derivatives, polyols and sugars, and methylamines. The osmolytes stabilize proteins and cellular stractures, and can also increase the osmotic pressure of the ceU [45]. This response... 

Tanaka, K., Ohta, K., Fritz, J. S., Lee, Y. S., and Shim, A. B., Ion-exclusion chromatography with conductimetric detection of aliphatic carboxyhc acids on an H -form cation-exchange resin column by elution with polyols and sugars, J. Chromatogr. A, 706, 385-393, 1995. 

Table II Detergency data of polyol and sugar esters expressed...

K. Tanaka and K. Ohta, lon-exdusion chromatography of ethanolamines on an anion-exchange resin by elution with polyols and sugars, /. Chromatogr. A,... 

The less hydrophilic polyols and sugar alcohols can also be used as polar heads for the design of bio-based hydrotropes. Glycerol being widely available as the by-product of the biodiesel industry, it has received particular interest. 

Glycosides, classical aromatic and ionic hydrotropes (Fig. 1) are nonvolatile, whereas some derivatives of polyols and sugar alcohols show... 

Alkoxides are readily formed from partially substituted polyols and sugars by treatment with sodium naphthalenide 19) in 1,2-dimethoxy-ethane solution and subsequent reaction with alkyl halides then produces ethers 20). The reaction sequence is simple to apply, and the method deserves further investigation. 

Kikuchi, Y., Kobayashi, K., and Aoyama, Y. (1992) Complexation of chiral glycols, steroidal polyols, and sugars with a multibenzenoid, achiral host as studied by induced circular-dichroism spectroscopy exciton chirality induction in resorcinol-aldehyde cyclotetramer and its use as a supramolecular probe for the assignments of stereochemistry of chiral guests, J. Am. Chem. Soc. 114, in press. 

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