The IUPAC name of this chemical is 8-hydroxyquinoline-5-sulfonic acid. With the CAS registry number 84-88-8, it is also named as 8-Hydroxychinolin-5-sulfonsaeure; Oxine-5-sulfonic acid. The product's categories are quinoline series, organic acids, hydroxyquinolines, quinolines, building blocks and heterocyclic building blocks. It is yellow to green crystalline which is soluble in water, slightly soluble in organic solvents. This product can be used for organic synthesis' intermediates and analytical reagents.

The other characteristics of this product can be summarized as: (1)ACD/LogP: -1.28; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 7.4): -4.83; (4)ACD/BCF (pH 5.5): 1; (5)ACD/BCF (pH 7.4): 1; (6)ACD/KOC (pH 5.5): 1; (7)ACD/KOC (pH 7.4): 1; (8)#H bond acceptors: 5; (9)#H bond donors: 2; (10)#Freely Rotating Bonds: 2; (11)Index of Refraction: 1.711; (12)Molar Refractivity: 53.98 cm³; (13)Molar Volume: 137.9 cm³; (14)Polarizability: 21.4×10^-24 cm³; (15)Surface Tension: 82.5 dyne/cm; (16)Rotatable Bond Count: 1; (17)Tautomer Count: 2; (18)Exact Mass: 225.009578; (19)MonoIsotopic Mass: 225.009578; (20)Topological Polar Surface Area: 95.9; (21)Heavy Atom Count: 15.

Preparation of 8-Hydroxyquinoline-5-sulfonic acid: It is obtained by 8-hydroxyquinoline from sulfonation. Cooling the fuming sulfuric acid below 10°C under stirring, and gradually adding 8-hydroxyquinoline when maintaining the temperature below 15°C. Heating after exhausted, then stirring 5h below 30°C . Place overnight. Take the reaction solution into the 8-10 times of the amount of water (based on 8-hydroxyquinoline) and control the temperature at 60°C. Precipitation, crystallization, and then placed overnight. Filtration, washing, drying at 100°C to get product. The yield is 87%.

Uses of 8-Hydroxyquinoline-5-sulfonic acid: It reacts with 2-chloro-1-phenyl-ethanone to get 8-(2-oxo-2-phenyl-ethoxy)-quinoline-5-sulfonic acid. This reaction needs reagent NaOH, catalytic agent tetra-n-butylammonium bromide and solvent CH₂Cl₂ and H₂O at temperature of 25 °C. The reaction time is 6 hours. The yield is 85%. 

When you are using this chemical, please be cautious about it as the following:
It is harmful if swallowed. And 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.

People can use the following data to convert to the molecule structure.
1. Smiles: c12c(c(ccc1S(O)(=O)=O)O)nccc2;
2. InChI: InChI=1/C9H7NO4S/c11-7-3-4-8(15(12,13)14)6-2-1-5-10-9(6)7/h1-5,11H,(H,12,13,14).

The following is the toxicity data which has been tested.