1-Naphthalenesulfonicacid, 3-hydroxy-4-[2-(2-hydroxy-1-naphthalenyl)diazenyl]-, sodium salt (1:1) (2538-85-4)

The IUPAC name of Calcon is sodium 4-[(2-hydroxynaphthalen-1-yl)hydrazinylidene]-3-oxonaphthalene-1-sulfonate. With the CAS registry number 2538-85-4, it is also named as 2,2'-Oxy-4-sulfononaphthaleneazonaphthalene. The product's categories are dyes and pigments; azo compounds; naphthylazo compounds; analytical chemistry; chelating reagents. It is dark brown to purple powder which is stable and incompatible with strong oxidizing agents. Calcon is soluble in water which is maroon, and also soluble in fibrinolytic hormone (ethylene glycol ether), slightly soluble in ethanol and acetone, insoluble in other organic solvents. In the concentrated sulfuric acid is blue, diluted generated lines red-brown precipitate; in concentrated nitric acid is yellow. Its solution plus hydrochloric acid generated yellow-brown precipitate; adding concentrated sodium hydroxide liquid to transmit to purplish black.

The other characteristics of this product can be summarized as: (1)#H bond acceptors: 7; (2)#H bond donors: 3; (3)#Freely Rotating Bonds: 5; (4)Rotatable Bond Count: 3; (5)Tautomer Count: 28; (6)Exact Mass: 416.044287; (7)MonoIsotopic Mass: 416.044287; (8)Topological Polar Surface Area: 127; (9)Heavy Atom Count: 29; (10)Complexity: 791; (11)Undefined Bond StereoCenter Count: 1; (12)Covalently-Bonded Unit Count: 2.

Preparation of Calcon: Coupling 1,2,4-acid oxygen body (1-amino-2-naphthol-4-sulfonic acid diazonium salt) and 2-naphthol, and then by salting, filtration and drying, we can get this product. Consumption of raw materials (kg/t): 1,2,4-acid oxygen body 3652; naphthoic acid 220; zinc sulfate 80; sodium hydroxide 120; ammonia 185; soda 165 (20%) 80.

Uses of Calcon: It is mainly used for dyeing wool loose hair and wool tops. And it is generally used for dyeing black, not for dyeing gray. In addition, it can also be used for coloring silk, nylon, and leather. Pure product can also be used as an indicator agent.

When you are using this chemical, please be cautious about it as the following:
It is irritating to eyes, respiratory system and skin. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. If you want to contact this product, you must wear suitable protective clothing, gloves and eye/face protection. 

People can use the following data to convert to the molecule structure. 
1. SMILES: [Na+].[O-]S(=O)(=O)c3cc(O)c(/N=N/c1c2ccccc2ccc1O)c4ccccc34;
2. InChI: InChI=1/C20H14N2O5S.Na/c23-16-10-9-12-5-1-2-6-13(12)19(16)21-22-20-15-8-4-3-7-14(15)18(11-17(20)24)28(25,26)27;/h1-11,23-24H,(H,25,26,27);/q;+1/p-1/b22-21+;.

The following are the toxicity data which has been tested.