Hydrazine sugars

Hydrogen peroxide, hydrazine, sugars Completely miscible... 

Hydrazine and its alkylated derivatives are used as rocket fuels in organic chemistry, substituted phenylhydrazines are important in the characterisation of sugars and other compounds, for example aldehydes and ketones containing the carbonyl group C=0. 

The principal reactions of this class of compounds are summarized in Scheme 172. In most of these reactions the reactive nucleophilic center is the terminal NHj group, although the other exocyclic nitrogen may also be involved, as shown by acetylation, which yields 284 and 285. However, the structure of compound 281 is not the one proposed in a recent report (1582) that attributes the attack to the other exocyclic nitrogen. The formation of osazones (287) from sugars, 2-hydrazinothiazoles, and hydrazine has been reported (525, 531). 

Various substituted N-hiomo- and A/-chloroureas have also been prepared (97). These compounds are useful for synthesis of oxazoUdinones, and also hydrazine, hydrazo, and azo compounds. A/-Bromourea [51918-81 -1] is useful for selective oxidation of sugar derivatives (98). 

The editors note with regret the passing of Laszld Mester on February 23, 1986. Mester worked extensively on hydrazine derivatives of sugars, and he contributed a notable article on the formazan reaction in Volume 13 of this series. 

Sugar lactones react readily with hydrazine to give crystalline derivatives useful for isolation and identification (127). Thus, addition of hydrazine to a reaction mixture containing an aldonolactone facilitates isolation of the product. The lactone may be regenerated from the hydrazide by treatment with nitrous acid (128). The phenylhydrazides obtained on treatment of aldonolactones with phenylhydrazine are also useful for characterization (129,130). 

Sugar 1-hydrazones are in equilibrium with the corresponding glycosyl hydrazine and will react with electrophiles to form triazolinyl sugars (Scheme 21) <83JHC1447>. Variation of the electrophile can provide a range of substituted triazoles. 

Anhydrous hydrazine, Cyanogen bromide, Isopropyl alcohol, Sodium nitrite, Sodium bicarbonate, Copper nitrate cryohydrate Sodium nitrate, Sodium chloride. Sugar, Charcoal powder Potassium nitrate. Sodium chlorate. Sugar, Charcoal powder Potassium nitrate. Potassium chlorate. Sugar, Charcoal powder Sodium nitrate. Potassium chlorate. Sugar, Charcoal powder 3-Pyridol, Ethylmethylamine, Formaldehyde, Pyridine, Dimethylcarbamoyl chloride. Sodium carbonate. Chloroform, Sodium sulfate, 1,10-Dibromodecane, Acetone, Acetonitrile, Charcoal, Ethyl acetate... 

Levulinic esters. Levulinic esters of sugars can also be prepared by Mukaiyama s method for esterification with 2-chloro-l-methylpyridinium iodide (8, 95-96). Deblocking of the ester group is possible with hydrazine hydrate (1 equivalent, 20°).1... 

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