Acid orange 19

Acid orange 19
Names
	Other names Sodium 4-hydroxy-3-(2-(4-methyl-3-((phenylamino)sulfonyl)phenyl)diazenyl)-1-naphthalenesulfonate
Identifiers
CAS Number	3058-98-8;
3D model (JSmol)	Interactive image;
ChemSpider	4675590;
ECHA InfoCard	100.019.363
EC Number	221-298-0;
PubChem CID	135601373;
CompTox Dashboard (EPA)	DTXSID90883728;
	InChI InChI=1S/C23H19N3O6S2.Na/c1-15-11-12-17(13-21(15)33(28,29)26-16-7-3-2-4-8-16)24-25-20-14-22(34(30,31)32)18-9-5-6-10-19(18)23(20)27;/h2-14,26-27H,1H3,(H,30,31,32);/q;+1/p-1 Key: KKJOSHGDFRDDGD-UHFFFAOYSA-M;
	SMILES CC1=C(C=C(C=C1)N=NC2=C(C3=CC=CC=C3C(=C2)S(=O)(=O)[O-])O)S(=O)(=O)NC4=CC=CC=C4.[Na+];
Properties
Chemical formula	C23H18N3NaO6S2
Molar mass	519.52 g·mol−1
Hazards
	GHS labelling:
Hazard statements	H412
Precautionary statements	P273, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Acid orange 19 is an azo dye that is used to color polyamide and wool fibers.^[1] It is usually available as a fine reddish-orange powder. The dye is soluble in water, producing an orange solution. When this solution is treated with concentrated hydrochloric acid, it turns red.^[2]

Acid orange 19 is prepared by azo coupling with 1-Hydroxynaphthalene-4-sulfonic acid.

Like most azo dyes, it is mildly toxic when orally ingested and has carcinogenic properties.^[3]

References

↑ Hunger, Klaus; Mischke, Peter; Rieper, Wolfgang; Raue, Roderich; Kunde, Klaus; Engel, Aloys (2005). "Azo Dyes". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a03_245. ISBN 978-3-527-30673-2.
↑ "3058-98-8 | CAS DataBase". www.chemicalbook.com. Retrieved 2026-06-07.
↑ John, Arooba; Yang, Hsi-Hsien; Muhammad, Sohaib; Khan, Zafar Iqbal; Yu, Haiyang; Luqman, Muhammad; Tofail, Matiba; Hussain, Muhammad Iftikhar; Awan, Muhammad Umer Farooq (2022-07-13). "Cross Talk between Synthetic Food Colors (Azo Dyes), Oral Flora, and Cardiovascular Disorders". Applied Sciences. 12 (14): 7084. doi:10.3390/app12147084. ISSN 2076-3417.

[Ullmann-1] Hunger, Klaus; Mischke, Peter; Rieper, Wolfgang; Raue, Roderich; Kunde, Klaus; Engel, Aloys (2005). "Azo Dyes". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a03_245. ISBN 978-3-527-30673-2.

[2] "3058-98-8 | CAS DataBase". www.chemicalbook.com. Retrieved 2026-06-07.

[3] John, Arooba; Yang, Hsi-Hsien; Muhammad, Sohaib; Khan, Zafar Iqbal; Yu, Haiyang; Luqman, Muhammad; Tofail, Matiba; Hussain, Muhammad Iftikhar; Awan, Muhammad Umer Farooq (2022-07-13). "Cross Talk between Synthetic Food Colors (Azo Dyes), Oral Flora, and Cardiovascular Disorders". Applied Sciences. 12 (14): 7084. doi:10.3390/app12147084. ISSN 2076-3417.

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