On the rearrangement of dehydro-l-ascorbic acid 2-p-mitcphenyl hydmzene to nitrogen heteiocyeles

ABSTRACT

The 3-hydroxyiminomethylpyrazole derivative II existed in keto-enol as evidenced by production of two acetyl derivatives IV and V, respectively. The enol form III gave the benzoyl derivative VI. Similarly, the 3-formylhydranone derivative VII gave the acetyl derivative IX. Condensation of VII with o- and m-nitrobenzaldehyde gave the benzylidene derivatives X and XI, respectively. The thiosemicarbazone XII also existed in the keto-enol forms. Both gave the acetyl bicyclic derivatives XIV and XV upon acetylation, and the enol form XIII gave the benzoyl derivative XVI. The 2-p- nitrophenylhydrazone 3-oxime XVII gave the triazole derivative XVIII upon oxidation with cupric chloride. The 2-p-nitrophenylhydrazone 3- oxime XVII gave the triazole derivative XVIII, which yielded the acetyl derivative XIX. Mild acetylation of XVII with AcOH gave the monoacetyl derivative XX which upon acetylation with Ac2O gave the triacetyl derivative XXI