The 5-Isoquinolinesulfonicacid, with the CAS registry number 27655-40-9, has the systematic name of isoquinoline-5-sulfonic acid. And the molecular formula of this chemical is C₉H₇NO₃S. It is a kind of white crystalline solid, and belongs to the following product categories: Quinolines, Isoquinolines & Quinoxalines; Organic acids; Aromatics Compounds; Aromatics; Sulfur & Selenium Compounds; Building Blocks; Heterocyclic Building Blocks; Isoquinolines.

The physical properties of 5-Isoquinolinesulfonicacid are as following: (1)ACD/LogP: 0.21; (2)# of Rule of 5 Violations: 0; (3)ACD/BCF (pH 5.5): 1; (4)ACD/BCF (pH 7.4): 1; (5)ACD/KOC (pH 5.5): 1; (6)ACD/KOC (pH 7.4): 1; (7)#H bond acceptors: 4; (8)#H bond donors: 1; (9)#Freely Rotating Bonds: 1; (10)Polar Surface Area: 64.64 Å²; (11)Index of Refraction: 1.675; (12)Molar Refractivity: 52.45 cm³; (13)Molar Volume: 139.5 cm³; (14)Polarizability: 20.79×10^-24cm³; (15)Surface Tension: 67.9 dyne/cm; (16)Density: 1.499 g/cm³.

Uses of 5-Isoquinolinesulfonicacid: It can be used to produce 5-isoquinolinesulfonyl chloride hydrochloride. This reaction will need reagents SOCl₂ and DMF. The reaction time is 2 hours with heating, and the yield is about 91%.

You should be cautious while dealing with this chemical. It is   toxic in contact with skin and by inhalation. It may cause burns, and may also cause cancer by inhalation. Therefore, you had better take the following instructions: Wear suitable protective clothing, gloves and eye/face protection, and in case of contacting with eyes, rinse immediately with plenty of water and seek medical advice; In case of accident or if you feel unwell, seek medical advice immediately (show label where possible); Avoid exposure - obtain special instruction before use.

You can still convert the following datas into molecular structure:
(1)SMILES: O=S(=O)(O)c1cccc2c1ccnc2
(2)InChI: InChI=1/C9H7NO3S/c11-14(12,13)9-3-1-2-7-6-10-5-4-8(7)9/h1-6H,(H,11,12,13)
(3)InChIKey: YFMJTLUPSMCTOQ-UHFFFAOYAR