The 3-Isothiazolecarboxylic acid is also known as Isothiazole-3-carboxylic acid. And  the CAS registry number of 3-Isothiazolecarboxylic acid is 4576-90-3, This chemical's molecular formula is C₄H₃NO₂S and molecular weight is 129.14. What's more, its systematic name is called 1,2-Thiazole-3-carboxylic acid. 

Physical properties about this chemical are: (1) ACD/LogP: 0.49; (2) # of Rule of 5 Violations: 0; (3) ACD/LogD (pH 5.5): -1.17; (4) ACD/LogD (pH 7.4): -2.52; (5) ACD/BCF (pH 5.5): 1; (6) ACD/BCF (pH 7.4): 1; (7) ACD/KOC (pH 5.5): 1; (8) ACD/KOC (pH 7.4): 1; (9) #H bond acceptors: 3; (10) #H bond donors: 1; (11) #Freely Rotating Bonds: 1; (12) Polar Surface Area: 67.43 Å²; (13) Index of Refraction: 1.617; (14) Molar Refractivity: 29.65 cm³; (15) Molar Volume: 84.6 cm³; (16) Surface Tension: 72 dyne/cm; (17) Density: 1.525 g/cm³; (18) Flash Point: 61.7 °C; (19) Enthalpy of Vaporization: 43.85 kJ/mol; (20) Boiling Point: 178.4 °C at 760 mmHg; (21) Vapour Pressure: 0.65 mmHg at 25 °C.

You can still convert the following datas into molecular structure:
(1) SMILES: O=C(O)c1nscc1
(2) InChI: InChI=1/C4H3NO2S/c6-4(7)3-1-2-8-5-3/h1-2H,(H,6,7)
(3) InChIKey: BMPVWNJQCJQBFW-UHFFFAOYAX