Molecular structure of 5-Formylthiophene-2-carboxylic acid (CAS NO.4565-31-5) is:

Product Name: 5-Formylthiophene-2-carboxylic acid
CAS Registry Number: 4565-31-5
Molecular Formula: C₆H₄O₃S
Systematic Name: 5-formylthiophene-2-carboxylic Acid
Molecular Weight: 156.16
Melting Point: 169 °C
Index of Refraction: 1.665 
Molar Refractivity: 38.32 cm³ 
Molar Volume: 103.1 cm³
Surface Tension: 69.4 dyne/cm 
Density: 1.514 g/cm³ 
Flash Point: 178.4 °C 
Enthalpy of Vaporization: 65.24 kJ/mol 
Boiling Point: 371.4 °C at 760 mmHg 
Vapour Pressure: 3.58E-06 mmHg at 25 °C 
SMILES: O=Cc1sc(C(=O)O)cc1
InChI: InChI=1/C6H4O3S/c7-3-4-1-2-5(10-4)6(8)9/h1-3H,(H,8,9) 
InChIKey: VFEAMMGYJFFXKV-UHFFFAOYAC 
Std. InChI: InChI=1S/C6H4O3S/c7-3-4-1-2-5(10-4)6(8)9/h1-3H,(H,8,9)
Std. InChIKey: VFEAMMGYJFFXKV-UHFFFAOYSA-N

Safty information about 5-Formylthiophene-2-carboxylic acid (CAS NO.4565-31-5) is:
Hazard Codes: Xi
Risk Statements: 36/37/38 
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements: 26-36 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S36:Wear suitable protective clothing.
Hazard Note: Irritant

 5-Formylthiophene-2-carboxylic acid , its cas register number is 4565-31-5. It also can be called 2-Thiophenecarboxylicacid, 5-formyl- ; 2-Formyl-5-thiophenecarboxylicacid .