Molecular Structure of Indole-5-carboxylic acid (CAS NO.1670-81-1):

IUPAC Name: 1H-Indole-5-carboxylic acid
Canonical SMILES: C1=CC2=C(C=CN2)C=C1C(=O)O
InChI: InChI=1S/C9H7NO2/c11-9(12)7-1-2-8-6(5-7)3-4-10-8/h1-5,10H,(H,11,12)
InChIKey: IENZCGNHSIMFJE-UHFFFAOYSA-N
Molecular Weight: 161.15738 [g/mol]
Molecular Formula: C₉H₇NO₂
XLogP3: 1.5
H-Bond Donor: 2
H-Bond Acceptor: 2 
EINECS: 216-799-6 
Index of Refraction: 1.725
Molar Refractivity: 45.45 cm³
Molar Volume: 114.4 cm³
Surface Tension: 71.6 dyne/cm
Density: 1.408 g/cm³
Flash Point: 207.6 °C
Enthalpy of Vaporization: 70.99 kJ/mol
Boiling Point: 419.6 °C at 760 mmHg
Vapour Pressure: 8.6E-08 mmHg at 25 °C
Appearance: light beige to yellow powder
Melting Point: 211-213 °C(lit.)
storage temp.: −20 °C
Product Categories: blocks; Carboxes; IndolesOxindoles; Indole / indoline / oxindole; Indole and Indoline; Indoles and derivatives; Indole; Indoles; Simple Indoles; Building Blocks; Heterocyclic Building Blocks

Safety Information of Indole-5-carboxylic acid (CAS NO.1670-81-1):
Hazard Codes: Xn,Xi
Risk Statements: 36/37/38-21/22 
R21/22:Harmful in contact with skin and if swallowed. 
R36/37/38:Irritating to eyes, respiratory system and skin.
Safety Statements: 22-24/25-36/37/39-26 
S22:Do not breathe dust. 
S24/25:Avoid contact with skin and eyes. 
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection. 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.
WGK Germany: 3
HazardClass: IRRITANT

 Indole-5-carboxylic acid (CAS NO.1670-81-1), its Synonyms are 2,3-Benzopyrrole-5-carboxylic acid ; 1H-indole-5-carboxylate ; 1H-indole-5-carboxylic acid ; 5-Indolecarboxylic acid .