The Acid yellow 11 is an organic compound with the formula C₁₆H₁₃N₄O₄S^.Na. The IUPAC name of this chemical is sodium 4-(3-methyl-5-oxo-4-phenyldiazenyl-4H-pyrazol-1-yl)benzenesulfonate. With the CAS registry number 6359-82-6, it is also named as benzenesulfonic acid, 4-[5-hydroxy-3-methyl-4-[(E)-2-phenyldiazenyl]-1H-pyrazol-1-yl]-, sodium salt (1:1). The product's category is Dyes and Pigments. Besides, it is a yellow to slightly orange powder, which should be stored in a dark cool and dry place. It is mainly used for dyeing wool, silk and fabric and coloring of paper, leather, paints, pharmaceuticals, cosmetics.

Physical properties about Acid yellow 11 are: (1)#H bond acceptors: 8; (2)#H bond donors: 2; (3)#Freely Rotating Bonds: 5; (4)Polar Surface Area: 128.35 Å².

Preparation: this chemical can be prepared by Aniline and 1-(sulfo-phenyl)-3-methyl-5-pyrazolone through coupling and salting.

When you are using this chemical, please be cautious about it as the following:
It can cause burns. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. Besides, this chemical is risk of explosion if heated under confinement. When you are using it, wear suitable gloves and eye/face protection. In case of accident or if you feel unwell seek medical advice immediately (show the label where possible).

You can still convert the following datas into molecular structure:
(1)SMILES: [Na+].[O-]S(=O)(=O)c1ccc(cc1)n3nc(C)c(/N=N/c2ccccc2)c3O
(2)InChI: InChI=1/C16H14N4O4S.Na/c1-11-15(18-17-12-5-3-2-4-6-12)16(21)20(19-11)13-7-9-14(10-8-13)25(22,23)24;/h2-10,21H,1H3,(H,22,23,24);/q;+1/p-1/b18-17+;
(3)InChIKey: WUKOPYOUBRDMHY-MQRXKLAQBO
(4)Std. InChI: InChI=1S/C16H14N4O4S.Na/c1-11-15(18-17-12-5-3-2-4-6-12)16(21)20(19-11)13-7-9-14(10-8-13)25(22,23)24;/h2-10,21H,1H3,(H,22,23,24);/q;+1/p-1/b18-17+;
(5)Std. InChIKey: WUKOPYOUBRDMHY-ZAGWXBKKSA-M