The IUPAC name of Pigment Red 57:1 is calcium (4Z)-4-[(4-methyl-2-sulfonatophenyl)hydrazinylidene]-3-oxonaphthalene-2-carboxylate. With the CAS registry number 5281-04-9, it is also named as 2-Naphthalenecarboxylic acid, 3-hydroxy-4-((4-methyl-2-sulfophenyl)azo)-, calcium salt; D & C Red no. 7. The other registry numbers are 106008-82-6, 11145-41-8, 116357-55-2, 116711-94-5, 12238-33-4, 12238-35-6, 12238-36-7, 12238-46-9, 12238-47-0, 128282-14-4, 1325-10-6, 149003-64-5, 217821-04-0, 37340-13-9, 39340-05-1, 53028-84-5, 53612-29-6, 57176-64-4, 57917-29-0, 60748-28-9 and 69458-81-7. In addition, ithis chemical is red powder which is insoluble in ethanol, slightly soluble in hot water, insoluble in cold water. Its absorption maximum lies at about 442 nm when dissolved in dimethylformamide.

The other characteristics of this product can be summarized as: (1)#H bond acceptors: 8; (2)#H bond donors: 3; (3)#Freely Rotating Bonds: 5; (4)Rotatable Bond Count: 2; (5)Tautomer Count: 18; (6)Exact Mass: 424.004198; (7)MonoIsotopic Mass: 424.004198; (8)Topological Polar Surface Area: 147; (9)Heavy Atom Count: 28; (10)Complexity: 763; (11)Defined Bond StereoCenter Count: 1; (12)Covalently-Bonded Unit Count: 2.

Uses OF Pigment Red 57:1: It is not only used to dye paint, ink, color paint and watercolor, but also used for coloring rubber, plastic cords, and household chemical products. When used as a food dye, it has E number E180. It is used to color cheese rind as well as a component in some lip balms. It is banned in some countries.

People can use the following data to convert to the molecule structure. 
1. SMILES: [Ca+2].[O-]S(=O)(=O)c3cc(C)ccc3/N=N/c1c2ccccc2cc(C([O-])=O)c1O;
2. InChI: InChI=1/C18H14N2O6S.Ca/c1-10-6-7-14(15(8-10)27(24,25)26)19-20-16-12-5-3-2-4-11(12)9-13(17(16)21)18(22)23;/h2-9,21H,1H3,(H,22,23)(H,24,25,26);/q;+2/p-2/b20-19+;.