The synthesis of 5‐acyl‐4‐aryl(alkyl)‐2‐aryl‐1,2,3‐triazole 1‐oxides by lead tetraacetate oxidation of mono‐ and bisarylhydrazones of α‐hydroxyimino‐β‐diketones

Abstract

The synthesis and lead tetraacetate oxidation of the title mono‐ and bis‐arylhydrazones to the corresponding 5‐acyl‐4‐aryl(alkyl)‐2‐aryl‐1,2,3‐triazole 1‐oxides is described.

Oxidative cyclization in the synthesis of 5‐ and 6‐membered N,O‐heterocycles

“…The synthesis of 2,4,5-trisubstituted 1,2,3-triazole 1-oxides 139 has been reported by the LTA oxidative cyclization of oxime hydrazones 137 or 138 (Scheme 28) [79].…”

Chemistry of 1,2,3-triazoles

“…Oxidative cyclization of 2-(2-arylhydrazono)acetaldehyde led to 2-aryl-1,2,3triazolium 1-oxides [256][257][258][259][260][261][262][263][264][265][266][267][268]. 1,2,3-Triazole derivatives 205 were easily transformed into 2-aryl-1,2,3-triazoles 206 by zinc reduction (Scheme 72) [259].…”

“…Currently, the following three drugs are used therapeutically in the treatment of non-insulin-dependent diabetes as antiglucosidases: 1-(2-hydroxyethyl)-2-(hydroxymethyl)-1-deoxynojirimycin (156, Miglitol or Glyset) [266], N-butyl-1-deoxynojirimycin (157, Zavesca) and voglibose (158, Vogli, Basen, or Prandial) (Scheme 21). New compounds with inhibitory activity on glycosidases led to the discovery that five-membered azaheterocycles mimic the sugar moieties; thus, various compounds containing the pyrrole, imidazole [267,268], tetrazolo-glyco-derivatives, and [1,2,3]-1Htriazole [269][270][271][272][273][274][275] groups were prepared and evaluated. Because the alkyl chain linker of N-butyl-1-deoxynojirimycin (157) does not have a deleterious effect on the inhibition of α-glucosidases on glycosidase activity, Zhou and coworkers [276] designed and synthesized a series of triazoles linked to nojirimycin (154) and evaluated their ability to inhibit α-glucosidase from Bacillus stearothermophilus.…”

Synthesis of 2,3-Diphenylquinoxaline 1-Oxides by Oxidative Cyclization of Benzil α-Arylimino Oximes

“…1,4 The synthesis and oxidation of α -arylimino oximes 3 to the title quinoxaline 1-oxides 4 is part of our effort to synthesize and oxidatively cyclize mixed heteroallylic derivatives of dicarbonyl compounds such as α -hydroxyimino aroylhydrazones of biacetyl, 5 arylhydrazones of biacetyl benzoylhydrazones, 6 and mono-and bisarylhydrazones of α -hydroxyimino β -diketones. 7 The condensation of the substituted anilines 1 with the ( E )-benzil monoxime was achieved in aqueous ethanol. The composition of the solvent mixture (vide infra) was established after tedious attempts to avoid the oiling out of the resulting reaction mixtures.…”