Aurin

Synthesis

Aurin was first prepared in 1834 by the German chemist Friedlieb Ferdinand Runge, who obtained it by distilling coal tar. He named it Rosölsäure or Rosaölsäure (red oil acid). In 1861, the German chemists Hermann Kolbe and Rudolf Schmitt presented the synthesis of aurin by heating oxalic acid and creosote (which contains phenol) in the presence of concentrated sulfuric acid. (Gradually, chemists realized that commercial aurin was not a pure compound, but was actually a mixture of similar compounds.See the papers of the English chemist Richard S. Dale and the German-English chemist Carl Schorlemmer and of the German chemist Heinrich Fresenius (de) (1847–1920).

• A review of findings about aurin up to 1872 appeared in:
• )

Aurin is formed by heating of phenol and oxalic acid in concentrated sulfuric acid. :[[File:Aurinsynthese.svg|400px]]

Safety

Aurin may cause eye, skin, and respiratory tract irritation. Ingestion and inhalation should be avoided.

Aurin was reported to have endocrine disruptor chemical (EDC) properties.

References

References

1. {{Sigma-Aldrich
2. (1834). "Ueber einige Produkte der Steinkohlendestillation". Annalen der Physik und Chemie.
3. (1859). "Note on rosolic acid". Quarterly Journal of the Chemical Society.
4. (1861). "Rother Farbstoff aus dem Kreosot". Annalen der Chemie.
5. Thorpe, Thomas Edward, ed., ''A Dictionary of Applied Chemistry'', 2nd ed. (London, England: Longmans, Green, and Co., 1913), vol. 5, "Triphenylmethane colouring matters," [https://books.google.com/books?id=c-ZYAAAAYAAJ&pg=PA551 p. 551.] From p. 551: "The researches of Dale and Schorlemmer, Zulkowski, and others have shown that common aurin consists of a mixture of a number of substances, which, in a pure state, are well crystallised."
6. (1 March 2000). "The Estrogen Receptor Relative Binding Affinities of 188 Natural and Xenochemicals: Structural Diversity of Ligands". Toxicological Sciences.