Molecular structure of 5-Carboxythiophene-2-boronic acid (CAS NO.465515-31-5) is:

Product Name: 5-Carboxythiophene-2-boronic acid
CAS Registry Number: 465515-31-5
IUPAC Name: 5-Boronothiophene-2-carboxylic acid
Molecular Weight: 171.9668 [g/mol]  
Molecular Formula: C₅H₅BO₄S  
H-Bond Donor: 3  
H-Bond Acceptor: 4
Melting Point: 135 °C
Storage temp.: Keep Cold
Index of Refraction: 1.616 
Molar Refractivity: 37.706 cm³ 
Molar Volume: 107.971 cm³
Surface Tension: 74.345 dyne/cm 
Density: 1.593 g/cm³ 
Flash Point: 236.592 °C 
Enthalpy of Vaporization: 76.868 kJ/mol 
Boiling Point: 467.594 °C at 760 mmHg 
Vapour Pressure: 0 mmHg at 25 °C 
Product Categories: BORONICACID;Boronic Acids & Esters;Thiophenes & Benzothiophenes;Boronic acid;Organoborons;Thiophene;Boronic Acids & Esters;Thiophenes & Benzothiophenes;Boronic Acids
Canonical SMILES: B(C1=CC=C(S1)C(=O)O)(O)O
InChI: InChI=1S/C5H5BO4S/c7-5(8)3-1-2-4(11-3)6(9)10/h1-2,9-10H,(H,7,8) 
InChIKey: OQGIKNPOYTVNNF-UHFFFAOYSA-N

Safty information about 5-Carboxythiophene-2-boronic acid (CAS NO.465515-31-5) is:
Hazard Codes: Xi
Risk Statements: 36/37/38 
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements: 26-36/37/39-37/39 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection. 
S37/39:Wear suitable gloves and eye/face protection.
Hazard Note: Irritant/Keep Cold
HazardClass: IRRITANT

 5-Carboxythiophene-2-boronic acid , its cas register number is 465515-31-5. It also can be called 2-Carboxythiophene-5-boronic acid; 5-Boronothiophene-2-carboxylic acid ; 5-(Dihydroxyboryl)-2-thiophenecarboxylic acid .It is a white to light yellow crystal powder.