Allura Red AC

Allura Red AC
Names
	Preferred IUPAC name Disodium 6-hydroxy-5-[(2-methoxy-5-methyl-4-sulfonatophenyl)diazenyl]naphthalene-2-sulfonate
	Other names Disodium 6-hydroxy-5-[(2-methoxy-5-methyl-4-sulfophenyl)azo]-2-naphthalenesulfonate; Allura Red; Food Red 17; C.I. 16035; FD&C Red 40; E129; 2-Naphthalenesulfonic acid, 6-hydroxy-5-((2-methoxy-5-methyl-4-sulfophenyl)azo)-, disodium salt;
Identifiers
CAS Number	25956-17-6 ;
3D model (JSmol)	Interactive image;
ChEMBL	ChEMBL174821 ;
ChemSpider	11588224 ;
ECHA InfoCard	100.043.047
E number	E129 (colours)
PubChem CID	33258;
UNII	WZB9127XOA ;
CompTox Dashboard (EPA)	DTXSID4024436 ;
	InChI InChI=1S/C18H16N2O8S2.2Na/c1-10-7-14(16(28-2)9-17(10)30(25,26)27)19-20-18-13-5-4-12(29(22,23)24)8-11(13)3-6-15(18)21;;/h3-9,21H,1-2H3,(H,22,23,24)(H,25,26,27);;/q;2+1/p-2/b20-19+;; Key: CEZCCHQBSQPRMU-LLIZZRELSA-L ; InChI=1/C18H16N2O8S2.2Na/c1-10-7-14(16(28-2)9-17(10)30(25,26)27)19-20-18-13-5-4-12(29(22,23)24)8-11(13)3-6-15(18)21;;/h3-9,21H,1-2H3,(H,22,23,24)(H,25,26,27);;/q;2+1/p-2/b20-19+;; Key: CEZCCHQBSQPRMU-JGGVBICHBN;
	SMILES [Na+].[Na+].COc3cc(c(C)cc3/N=N/c1c2ccc(cc2ccc1O)S([O-])(=O)=O)S([O-])(=O)=O;
Properties
Chemical formula	C18H14N2Na2O8S2
Molar mass	496.42 g·mol−1
Appearance	Red powder
Melting point	> 300 °C (572 °F; 573 K)
Hazards
NFPA 704 (fire diamond)	1 1 0
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Allura Red AC, also known as FD&C Red 40 or E129, is a red azo dye commonly used in food. It was developed in 1971 by the Allied Chemical Corporation, who gave the substance its name.

It is usually supplied as its red sodium salt but can also be used as the calcium and potassium salts. These salts are soluble in water. In solution, its maximum absorbance lies at about 504 nm.^: 921

Allura Red AC is manufactured by azo coupling between diazotized 5-amino-4-methoxy-2-toluenesulfonic acid and 6-hydroxy-2-naphthalene sulfonic acid.