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Record Information
StatusExpected but not Quantified
Creation Date2012-09-11 17:52:28 UTC
Update Date2019-07-23 06:12:01 UTC
Secondary Accession Numbers
  • HMDB32884
Metabolite Identification
Common NameAllura red AC
DescriptionColour additive used in gelatins, puddings, custards, beverages, sauces, toppings, fruits, dairy products, bakery products, jams, jellies, condiments, meat and poultry Allura Red AC is a red azo dye that goes by several names including: Allura Red, Food Red 17, C.I. 16035, FD&C Red 40, 2-naphthalenesulfonic acid, 6-hydroxy-5-((2-methoxy-5-methyl-4-sulfophenyl)azo)-, disodium salt, and disodium 6-hydroxy-5-((2-methoxy-5-methyl-4-sulfophenyl)azo)-2-naphthalene-sulfonate. It is used as a food dye and has the E number E129. Allura Red AC was originally introduced in the United States as a replacement for the use of amaranth as a food coloring. Allura Red AC is one of many High Production Volume Chemicals. Some manufacturers of Allura Red AC include: Asim Products, Sanchi Chemicals Pvt. Ltd., and Warner-Jenkinson Europe Ltd. Upon its introduction into the market, there were fears that Allura Red AC was carcinogenic; however, studies have since shown that this is not the case.[citation needed] The initial reports of its consumption causing tumors have since been shown to have been caused by the presence of para-cresidine.[citation needed] Although para-cresidine is an important reactant in the manufacture of Allura Red AC and is a known carcinogen, further studies conducted since have found no trace of para-cresidine to be present in food-grade Allura Red AC.[citation needed].
6-Hydroxy-5-[(2-methoxy-5-methyl-4-sulfophenyl)azo]-2-naphthalenesulfonic acid, 9ciHMDB
Allura redHMDB
Allura red ac dyeHMDB
C.I. 16035HMDB
C.I. FOOD red 17HMDB
Curry redHMDB
FD & C red no. 40HMDB
FD And C red no. 40HMDB
FD&C red no. 40HMDB
FOOD Red no. 40HMDB
Red no. 40HMDB
6-Hydroxy-5-[(e)-2-(2-methoxy-5-methyl-4-sulphophenyl)diazen-1-yl]naphthalene-2-sulphonic acidGenerator
Chemical FormulaC18H16N2O8S2
Average Molecular Weight452.458
Monoisotopic Molecular Weight452.034806878
IUPAC Name6-hydroxy-5-[(E)-2-(2-methoxy-5-methyl-4-sulfophenyl)diazen-1-yl]naphthalene-2-sulfonic acid
Traditional Name6-hydroxy-5-[(E)-2-(2-methoxy-5-methyl-4-sulfophenyl)diazen-1-yl]naphthalene-2-sulfonic acid
CAS Registry Number25956-17-6
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as 2-naphthalene sulfonates. These are organic aromatic compounds that contain a naphthalene moiety that carries a sulfonic acid group at the 2-position. Naphthalene is a bicyclic compound that is made up of two fused benzene ring.
KingdomOrganic compounds
Super ClassBenzenoids
Sub ClassNaphthalene sulfonic acids and derivatives
Direct Parent2-naphthalene sulfonates
Alternative Parents
  • 2-naphthalene sulfonic acid or derivatives
  • 2-naphthalene sulfonate
  • 2-naphthol
  • Benzenesulfonate
  • Arylsulfonic acid or derivatives
  • Benzenesulfonyl group
  • 1-sulfo,2-unsubstituted aromatic compound
  • Methoxyaniline
  • Anisole
  • Phenoxy compound
  • Phenol ether
  • Methoxybenzene
  • Alkyl aryl ether
  • 1-hydroxy-2-unsubstituted benzenoid
  • Toluene
  • Monocyclic benzene moiety
  • Organic sulfonic acid or derivatives
  • Sulfonyl
  • Organosulfonic acid
  • Organosulfonic acid or derivatives
  • Azo compound
  • Ether
  • Propargyl-type 1,3-dipolar organic compound
  • Organic 1,3-dipolar compound
  • Organopnictogen compound
  • Organosulfur compound
  • Organooxygen compound
  • Organonitrogen compound
  • Organic oxygen compound
  • Organic oxide
  • Organic nitrogen compound
  • Hydrocarbon derivative
  • Aromatic homopolycyclic compound
Molecular FrameworkAromatic homopolycyclic compounds
External DescriptorsNot Available


Biological location:


Biological role:

Industrial application:

Physical Properties
Experimental Properties
Melting Point300 °CNot Available
Boiling PointNot AvailableNot Available
Water Solubility225 mg/mL at 25 °CNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.02 g/LALOGPS
pKa (Strongest Acidic)-3ChemAxon
pKa (Strongest Basic)-1.7ChemAxon
Physiological Charge-2ChemAxon
Hydrogen Acceptor Count10ChemAxon
Hydrogen Donor Count3ChemAxon
Polar Surface Area162.92 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity111.56 m³·mol⁻¹ChemAxon
Polarizability43.42 ųChemAxon
Number of Rings3ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0079-0194400000-18e286940f518096ed97Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-01vo-3154920000-1e2da1baaba41d420686Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0udi-0000900000-d0a5b7281767780579c9Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0udi-0312900000-ad84ed764e2434380742Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0avl-2329000000-6bd858afebf71d6ff8e4Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0udi-0001900000-c1fb3bb729e1a24a69cdSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0uk9-0115900000-08ef62471db37994b26cSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0fl0-0390000000-50ed853957d4d7d0df44Spectrum
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
Biospecimen LocationsNot Available
Tissue LocationsNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDFDB010866
KNApSAcK IDNot Available
Chemspider ID26351025
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkAllura Red AC
METLIN IDNot Available
PubChem CompoundNot Available
PDB IDNot Available
ChEBI IDNot Available
Food Biomarker OntologyNot Available
VMH IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. (). Yannai, Shmuel. (2004) Dictionary of food compounds with CD-ROM: Additives, flavors, and ingredients. Boca Raton: Chapman & Hall/CRC.. .