Pyrouric acid

A previously unknown concrete acid calculus) was separated by Scheele from urinary calculi (uric acid) and shown to be present in small quantities in urine. The red colour (murexide) formed on evaporating it with nitric acid was observed. By heating uric acid he obtained a sublimate (afterwards called pyrouric acid) which he thought was similar to succinic acid it is really cyanuric acid. ... 

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