Titan yellow

{{short description|Organic dye}}

{{Chembox

| ImageFile = Titan yellow.svg

| ImageSize = 280

| ImageAlt = Structural formula of titan yellow, sodium salt

| ImageFile1 = Titan yellow sodium 3D spacefill.png

| ImageSize1 = 280

| ImageAlt1 = Ball-and-stick model of the titan yellow molecule, sodium salt

| PIN = Disodium 2,2′-[(1E)-triaz-1-ene-1,3-diyldi(4,1-phenylene)]bis(6-methyl-1,3-benzothiazole-7-sulfonate)

| OtherNames = Thiazole Yellow G; Clayton Yellow; C.I. 19540; C.I. Direct Yellow 9

| Section1 = {{Chembox Identifiers

| CASNo = 1829-00-1

| CASNo_Ref = {{cascite|correct|CAS}}

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = XL4T724PIZ

| PubChem = 73217

| ChemSpiderID = 65972

| SMILES = [Na+].[Na+].[O-]S(=O)(=O)c2c(ccc1nc(sc12)c6ccc(/N=N/Nc5ccc(c3nc4ccc(c(c4s3)S([O-])(=O)=O)C)cc5)cc6)C

| InChI = InChI=1S/C28H21N5O6S4.2Na/c1-15-3-13-21-23(25(15)42(34,35)36)40-27(29-21)17-5-9-19(10-6-17)31-33-32-20-11-7-18(8-12-20)28-30-22-14-4-16(2)26(24(22)41-28)43(37,38)39;;/h3-14H,1-2H3,(H,31,32)(H,34,35,36)(H,37,38,39);;/q;2*+1/p-2

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| Section2 = {{Chembox Properties

| Formula = C₂₈H₁₉N₅Na₂O₆S₄

| MolarMass = 695.720 g/mol

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| Section3 = {{Chembox Hazards

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Titan yellow is a compound with formula C₂₈H₁₉N₅Na₂O₆S₄. It is a triazene dye used as a stain and fluorescent indicator in microscopy.[http://www.sigmaaldrich.com/US/en/product/sial/88390 Thiazole Yellow G] at Sigma-Aldrich It is also used for the colorimetric indication of various compounds and is an acid-base indicator. As an acid-base indicator, it changes color from yellow to red between pH 12 and pH 13.