Indoxyl
{{chembox
| verifiedrevid = 443875638
| ImageFile=Indoxyl.svg
| ImageSize=140
| ImageAlt = Skeletal formula
| ImageAlt1 = Ball-and-stick model
| PIN=1H-Indol-3-ol
| OtherNames=
|Section1={{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo=480-93-3
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = BZ24HY3WPJ
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 17840
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 45861
| EINECS = 689-424-0
| KEGG_Ref = {{keggcite|correct|kegg}}
| KEGG = C05658
| InChI = 1/C8H7NO/c10-8-5-9-7-4-2-1-3-6(7)8/h1-5,9-10H
| InChIKey = PCKPVGOLPKLUHR-UHFFFAOYAR
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C8H7NO/c10-8-5-9-7-4-2-1-3-6(7)8/h1-5,9-10H
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = PCKPVGOLPKLUHR-UHFFFAOYSA-N
| PubChem=50591
| SMILES = Oc2c1ccccc1[nH]c2
}}
|Section2={{Chembox Properties
| Formula=C8H7NO
| MolarMass=133.14728
| Appearance=
| Density=
| MeltingPt=
| BoilingPt=
| Solubility=
}}
|Section3={{Chembox Hazards
| GHSPictograms = {{GHS06}}{{GHS09}}
| GHSSignalWord = Danger
| HPhrases = {{H-phrases|302|311|319|400}}
| PPhrases = {{P-phrases|264|270|273|280|301+312|302+352|305+351+338|312|322|330|337+313|361|363|391|405|501}}
| MainHazards=
| FlashPt=
| AutoignitionPt =
}}
}}
In organic chemistry, indoxyl is a nitrogenous substance with the chemical formula: C8H7NO.{{Katritzky2nd}}{{cite book |last=Clayden |first=J. |last2=Greeves |first2=N. |last3=Warren |first3=S. |last4=Wothers |first4=P. |title=Organic Chemistry |publisher=Oxford University Press |location=Oxford, Oxfordshire |year=2001 |isbn=0-19-850346-6 |url=https://archive.org/details/organicchemistry00clay_0 |url-access=registration }} Indoxyl is isomeric with oxindol and is obtained as an oily liquid.
Preparation
The Heumann indigo synthesis starts from anthranilic acid:
:Image:Synthesis Indoxyl.svg to give phenylglycine-o-carboxylic acid. When treated in molten sodium carbonate, the 2-Indoxycarboxylic acid (3) decarboxylates to give indoxyl (4) .]]
In nature indoxyl is derived from indican, which is a glycoside. The hydrolysis of indican yields β-D-glucose and indoxyl.
Indigo dye is a product of the mild oxidation of indoxyl.
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).{{Cite book|title=CRC - Handbook of Chemistry and Physics|last=Lide|first=David|publisher=CRC press LLC|year=1998|isbn=0-8493-0479-2|pages=Section 8 page 3}}