Osotriazoles, phenyl

In 1944, Hann and Hudson found that, when refluxed with cupric sulfate, osazones are converted into colorless triazole derivatives which they designated osotriazoles. They determined the structure of the d-orahmo-hexulose derivative by means of the following reactions (1) it gave a tetraacetate and a tetrabenzoate which could be saponified to the parent osotriazole, indicating the presence of four free hydroxyl groups therein (2) on periodate oxidation, 3 moles of oxidant were consumed per mole of (71), giving 1 mole of formaldehyde, 2 moles of formic acid, and a known compound, 4-formyl-2-phenyl-l, 2,3-triazole (72). 

The sugar residues in osotriazoles can be readily acetylated, benzoylated (see Table II, p. 117), or p-toluenesulfonated. Further, as previously stated, osotriazoles can be oxidized with sodium periodate or red lead to give 4-formyl-2-phenyl-l,2,3-triazole (3), or with 20% nitric acid, aqueous potassium permanganate, or ceric sulfate to give 2-phenyl-l,2,3-triazole-4-carboxylic acid (5). 

In the controversy on the mechanism of osazone formation, it was found that glucose-f-t is converted into the phenylosazone and the phenyl-osotriazole without loss of tritium." This finding was taken as evidence against formation, by the Amadori rearrangement, of an intermediate having two hydrogen atoms on C-1 as in Weygand s scheme" B. 

However, 1,2-bisphenylhydrazones (osazones) on heating or on oxidation yield 2-phenyl-1,2,3-triazoles 13 (osotriazoles) ... 

Phenyl-2, l, 3 -Triazolol-4, 5 4,5-[1.2,3-Triazole] (2-Phenyl-[triazolo[4, 4 4,5-triazole], N-Phenyl-C,C-azimino-osotriazol [Ger] orPhenyl-osotrlazolazimid[Ger]). 

Alditol-l-yl)-2-phenyl-5-phenylazo-l,2,3-triazoles (osotriazole forma-zans) (669) were obtained by cyclization of the corresponding osazone formazans (668) with acetic acid (60BSF350 62BSF381) (Scheme 177). 

Osotriazoles of diketones previously had been described by von Pech-mann 2 0) who obtained them by the oxidation of the corresponding di-hydrazones. The corresponding osotriazoles of the sugars are formed directly by the action of copper sulfate. The formation of the phenyl-D-glucoso-triazole (II) from glucose phenylosazone (I) is illustrated. Its structure is demonstrated by oxidation with periodic acid to the 2-phenyl-4-formyl-osotriazole (III) which is identical with the product obtained previously by von Pechmann from mono-0-acetyldinitrosoacetone phenylhydrazone (IV). 

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