Molecule structure of 3-Carboxymethylenephthalide (CAS NO.4743-57-1) :

IUPAC Name: (2Z)-2-(3-oxo-2-benzofuran-1-ylidene)acetic acid 
Molecular Weight: 190.15224 g/mol
Molecular Formula: C₁₀H₆O₄ 
Density: 1.612 g/cm³ 
Melting Point: 287 °C
Boiling Point: 362.9 °C at 760 mmHg 
Flash Point: 151 °C
Index of Refraction: 1.749
Molar Refractivity: 47.99 cm³
Molar Volume: 117.9 cm³
Polarizability: 19.02*10^-24 cm³
Surface Tension: 91 dyne/cm 
Enthalpy of Vaporization: 64.25 kJ/mol
Vapour Pressure: 6.65E-06 mmHg at 25 °C 
XLogP3-AA: 1.2
H-Bond Donor: 1
H-Bond Acceptor: 4
Rotatable Bond Count: 1
Exact Mass: 190.026609
MonoIsotopic Mass: 190.026609
Topological Polar Surface Area: 63.6
Heavy Atom Count: 14
Complexity: 305
Canonical SMILES: C1=CC=C2C(=C1)C(=CC(=O)O)OC2=O
Isomeric SMILES: C1=CC=C2C(=C1)/C(=C/C(=O)O)/OC2=O
InChI: InChI=1S/C10H6O4/c11-9(12)5-8-6-3-1-2-4-7(6)10(13)14-8/h1-5H,(H,11,12)/b8-5-
InChIKey of 3-Carboxymethylenephthalide (CAS NO.4743-57-1) : XKMGDVJBAWUUDZ-YVMONPNESA-N

Reported in EPA TSCA Inventory.

Moderately toxic by ingestion. When heated to decomposition it emits acrid smoke and irritating vapors.

 3-Carboxymethylenephthalide (CAS NO.4743-57-1) is also called  (3-Oxo-1(3H)-isobenzofuranylidene)acetic acid ;
3-Oxo-delta(sup 1,alpha)-phthalanacetic acid ; AI3-18620 ; Acetic acid, (3-oxo-1(3H)-isobenzofuranylidene)- ; Acetic acid, (3-oxo-1(3H)-isobenzofuranylidene)- (9CI) ; delta(sup 1,alpha)-Phthalanacetic acid, 3-oxo- .