Sudan Red 7B, also known as Solvent Red 19, Ceres Red 7B, Fat Red 7B, Hexatype carmine B, Lacquer red V3B, Oil violet, Organol bordeaux B, Sudanrot 7B, Typogen carmine, and C.I. 26050, is a red diazo dye.^[1][2][3] Chemically it is N-ethyl-1-[[p-(phenylazo)phenyl]azo]-2-naphthalenamine. It is soluble in oils and insoluble in water.

Sudan Red 7B

Names
Preferred IUPAC name N-Ethyl-1-{[4-(phenyldiazenyl)phenyl]diazenyl}naphthalen-2-amine
Other names Solvent Red 19; Ceres Red 7B; Fat Red 7B; Hexatype carmine B; Lacquer red V3B; Oil violet; Organol bordeaux B; Sudanrot 7B; Typogen carmine; C.I. 26050; N-ethyl-1-[[p-(phenylazo)phenyl]azo]-2-naphthalenamine
Identifiers
CAS Number	6368-72-5 Y
3D model (JSmol)	Interactive image
ChemSpider	55325 Y
ECHA InfoCard	100.026.238
KEGG	C19529 N
PubChem CID	61396
UNII	8QUH39Y06P Y
CompTox Dashboard (EPA)	DTXSID4064266
InChI InChI=1S/C24H21N5/c1-2-25-23-17-12-18-8-6-7-11-22(18)24(23)29-28-21-15-13-20(14-16-21)27-26-19-9-4-3-5-10-19/h3-17,25H,2H2,1H3/b27-26+,29-28+ Y Key: VKWNTWQXVLKCSG-ZDXBJJIESA-N Y InChI=1/C24H21N5/c1-2-25-23-17-12-18-8-6-7-11-22(18)24(23)29-28-21-15-13-20(14-16-21)27-26-19-9-4-3-5-10-19/h3-17,25H,2H2,1H3/b27-26+,29-28+ Key: VKWNTWQXVLKCSG-ZDXBJJIEBU
SMILES N(=N/c3ccc(/N=N/c1c2c(ccc1NCC)cccc2)cc3)\c4ccccc4
Properties
Chemical formula	C24H21N5
Molar mass	379.467 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

It is used in biology for staining, and in industry as one of the fuel dyes. It can be also present in red laser toners.