Indoxyl can be found in urine and is titrated with Obermayer's reagent, which is a dilute solution of ferric chloride (FeCl3) in hydrochloric acid (HCl).[3]
References
^Katritzky, A. R.; Pozharskii, A. F. (2000). Handbook of Heterocyclic Chemistry (2nd ed.). Academic Press. ISBN0080429882.
^Clayden, J.; Greeves, N.; Warren, S.; Wothers, P. (2001). Organic Chemistry. Oxford, Oxfordshire: Oxford University Press. ISBN0-19-850346-6.
^Lide, David (1998). CRC - Handbook of Chemistry and Physics. CRC press LLC. pp. Section 8 page 3. ISBN0-8493-0479-2.