D-erythro-2,3-Hexodiulosono-1,Clactone 2-arylhydrazones (2) were prepared by condensation of dehydro-D-arubino-ascorbic acid with the desired arylhydrazine. Reaction of 2 with hydroxylamine gave the 2-arylhydrazone 3oximes (3). On boiling with acetic anhydride, 3 gave 2-aryl-4-(2,3-di-O-acetyl-Derythro-glycerol-l-y1)-1,2,3-triazole-5-carboxylic acid 5,1'-lactone (S), whereas the unacetylated triazole derivatives were obtained upon reaction of 3 with bromine in water. On treatment of 5 with hydrazine hydrate, 2-aryl-4-(D-erythro-glycerol-lyl)-1,2,3-triazole-5carboxylic acid 5hydrazides (6) were obtained. Acetylation of 6 gave the hexaacetyl derivatives. Similarly, treatment of 5 with liquid ammonia gave the triazolecarboxamides (12). Vigorous acetylation of 12 with boiling acetic anhydride gave tetraacetates, whereas acetylation with acetic anhydride-pyridine gave triacetates. Periodate oxidation of 6 gave the 2-aryl-4-formyl-1,2,3-triazole-5carboxylic acid 5-hydrazides (S), and, on reduction, 8 gave the 2-aryl-4-(hydroxymethyl)-1,2,3-triazole-5-carboxylic acid 5-hydrazides, characterized as acetates. Similarly, periodate oxidation of 12 gave the triazolealdehyde (15)) and reduction of 15 gave the hydroxymethyl derivatives (16). Acetylation of 16 gave the monoand di-acetates, and, on reaction with o-phenylenediamine, 15 afforded the triazoleimidazole. Controlled reaction of 3 with sodium hydroxide, followed by neutralization, gave 3-(D-eryfhro-glyceroI-l-yl)-4,.5-isoxazolinedione 4-arylhydrazones. Reaction of 3 with HBr-HOAc gave S-0-acetyl-6-bromo-6-deoxy-D-erythro-2,3-hexodiulosono-1,4-lactone 2-arylhydrazone 3-oximes (21). Compounds 21 were converted into 4-(2-0-acetyl-3-bromo-3-deoxy-D-erythro-glycerol-l-y1)-2aryl-1,2,3-triazole-5-carboxylic acid 5,1'-lactone on treatment with acetic anhydride. DISCUSSION AND RESULTS Because of our continued interest in the synthesis of nitrogen heterocycles *Triazole Derivatives from Dehydroascorbic Acids, Part V. For Part IV, see ref. 1.