Oxamic acid ethyl ester

Thiazolo[2,3-c][l,2,4]triazines 658 were prepared (84LA1302) regio-specifically by cyclizing 2-hydrazono-2-thiazoline 659 with glyoxylic acid or ester. They had herbicidal activity. Condensation of 659 with oxamic acid ethyl ester gave hydrazide 660, which was cyclized with sodium... 

Ethyl thioamidooxalate Oxamic acid, 2-thio-, ethyl ester (8) Acetic acid, aminothioxo-, ethyl ester (9) (16982-21-1)... 

Works on the oxidation of uric acid has unequivocally established the triazine structure > ° (9) of oxonic acid. This is further confirmed by the straightforward synthesis described by Piskala and Gut. ° The reaction of biuret (11) with potassium ethyloxalate yielded a potassium salt (24), that with ethyl oxamate, the amide of oxonic acid (25). Both these compounds were converted to 5-azauracil. An analogous reaction with diethyloxalate which should produce an ester of oxonic acid resulted in a mixture of urethane and parabanic acid, however. 

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