purpuric acid

Named by Dr W. H. Wollaston "from its remarkable property of forming compounds with most bases of a red or purple colour" (as reported by William Prout in Philosophical Transactions of the Royal Society of London, Vol. 108 in 1818, pages 420-428).

purpuric acid (uncountable)

1. (chemistry) C₈H₅N₅O₆, a nitrogenous acid that yields alloxan and uramil when hydrolysed, known for its purple salts.

At first, the name was applied to a "substance discovered by Prout, which had neither a purple colour, nor possessed acid properties, but it was so named, because it was extracted, by means of an acid, from purpurate of ammonia", and its composition was thought to be H₈C₁₆O₁₀N₁₀ (as reported in the London and Edinburgh Philosophical Magazine and Journal of Science, volume XV, July—December 1839, Daid Brewster, Richard Taylor, Richard Phillips, eds, page 491).

• murexide, its ammonium salt