Phenylhydrazides

Early experiments with pyridine-2,3-dicarboxylic mono- and bis-phenylhydrazides were unsuccessful (32JIC145), but later these were cyclized in acetic acid (66CPBIOIO) to give only the 7-phenylpyrido[2,3-[Pg.242]

The 3,4-pyridinedicarboxylic phenylhydrazide (337), however, did cyclize in one of the earliest pyrido[3,4-higher temperature (12M(33)393, 66CPBIOIO). 

Phenylhydrazides have been prepared from amino acid esters and phenylhydrazine in 70% yield they are cleaved by oxidation [Cu(OAc)2, 95°, 10 min, 67% yield FeCyi NHCl, 96°, 14 min, 85% yield ]. 

Phenylhydrazides have been prepared from amino acid esters and phenylhy-drazine in 70% yield. ... 

Camphor is the ketone of the alcohol borneol and forms a number of well-characterised crystalline derivatives. Amongst these are the semi-carbazone, the phenylhydrazide, and the oxime, all characteristic of bodies containing the. CO. group. -The semi-carbazone,... 

Levi, Hawkins and Hibbert6 have recently confirmed the structure for L. mesenteroides dextran proposed by Fowler, Buckland, Brauns and Hibbert.34 Completely methylated dextran in an over-all yield of 71% was obtained by three methylations with dimethyl sulfate and sodium hydroxide, followed by six modified Muskat methylations. The methylated dextran was hydrolyzed at 140° with methanolic hydrogen chloride, and the mixture of methylated glucosides, obtained in 95% yield, was quantitatively separated by fractional distillation. 2,3-Di-methyl-D-glucose was identified by means of the phenylhydrazide of the corresponding D-gluconic acid. 

The extension of the salt-acid,27 phenylhydrazide,28 and amide rules29 to the derivatives of the 2-(hydroxymethyl) sugars by Schmidt and Weber-Molster30 indicated that the configuration of C2 in hamamelonic acid is the same as that of D-ribonic acid. Finally, the d-ribo configuration of the sugar was established by the synthesis of hamamelonic acid and its C2 epimer from D-ery/ftro-pentulose31 by the cyanohydrin reaction of Fischer and Kiliani. 

In contrast to aldoses, ketoses, and compound 2, which, on treatment with phenylhydrazine, form phenylosazones, compound 4, under the same conditions, yields116 the phenylhydrazone of aldehydo-D-glucuronic phenylhydrazide (69). In a series of papers, Momose and coworkers117 120 described the synthesis of N-... 

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). 

Silver l-benzeneazothiocarbonyl-2-phenylhydrazide, 3605 Sodium 5(5/-hydroxytetrazol-3/-ylazo)tetrazolide, 0682... 

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