The 4H-1-Benzopyran-3-carbonitrile,4-oxo-, with the CAS registry number 50743-17-4, has the systematic name of 4-oxo-4H-chromene-3-carbonitrile. It is a kind of light yellow crystalline powder, and belongs to the product category of Chromones. And the molecular formula of the chemical is C₁₀H₅NO₂.

The characteristics of 4H-1-Benzopyran-3-carbonitrile,4-oxo- are as followings: (1)ACD/LogP: 1.06; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 1.06; (4)ACD/LogD (pH 7.4): 1.06; (5)ACD/BCF (pH 5.5): 3.79; (6)ACD/BCF (pH 7.4): 3.79; (7)ACD/KOC (pH 5.5): 90.37; (8)ACD/KOC (pH 7.4): 90.37; (9)#H bond acceptors: 3; (10)#H bond donors: 0; (11)#Freely Rotating Bonds: 0; (12)Polar Surface Area: 50.09 Å²; (13)Index of Refraction: 1.621; (14)Molar Refractivity: 44.7 cm³; (15)Molar Volume: 127 cm³; (16)Polarizability: 17.72×10^-24cm³; (17)Surface Tension: 58.4 dyne/cm; (18)Density: 1.34 g/cm³; (19)Flash Point: 119.5 °C; (20)Enthalpy of Vaporization: 51.69 kJ/mol; (21)Boiling Point: 278.3 °C at 760 mmHg; (22)Vapour Pressure: 0.0043 mmHg at 25°C. 

Uses of 4H-1-Benzopyran-3-carbonitrile,4-oxo-: It can react with propylamine to produce 2-amino-4-oxo-4H-chromene-3-carbaldehyde. This reaction will need menstruum ethanol. The reaction time is 4 hours with heating, and the yield is about 75%. 

You should be cautious while dealing with this chemical. It irritates to eyes, respiratory system and skin, and it is also harmful by inhalation, in contact with skin and if swallowed. Therefore, you had better take the following instructions: Wear suitable protective clothing, gloves and eye/face protection, and if in case of contacting with eyes, rinse immediately with plenty of water and seek medical advice.

Addtionally, the following datas could be converted into the molecular structure:
(1)SMILES: O=C1c2c(O/C=C1/C#N)cccc2
(2)InChI: InChI=1/C10H5NO2/c11-5-7-6-13-9-4-2-1-3-8(9)10(7)12/h1-4,6H
(3)InChIKey: SFWNPLLGXKJESA-UHFFFAOYAC