The 4H-1-Benzopyran-4-one,5-methoxy-2-phenyl-, with the CAS registry number 42079-78-7, is also known as 5-Methoxyflavone. It belongs to the product category of Mono-substituted Flavones. Its EINECS number is 255-652-0. This chemical's molecular formula is C₁₆H₁₂O₃ and molecular weight is 252.26. What's more, its systematic name is 5-methoxy-2-phenyl-4H-chromen-4-one. It should be sealed and stored in a cool and dry place. 

Physical properties of 4H-1-Benzopyran-4-one,5-methoxy-2-phenyl- are: (1)ACD/LogP: 3.47; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 3.47; (4)ACD/LogD (pH 7.4): 3.47; (5)ACD/BCF (pH 5.5): 256.03; (6)ACD/BCF (pH 7.4): 256.03; (7)ACD/KOC (pH 5.5): 1842.71; (8)ACD/KOC (pH 7.4): 1842.71; (9)#H bond acceptors: 3; (10)#H bond donors: 0; (11)#Freely Rotating Bonds: 2; (12)Polar Surface Area: 35.53 Å²; (13)Index of Refraction: 1.614; (14)Molar Refractivity: 70.88 cm³; (15)Molar Volume: 203.2 cm³; (16)Polarizability: 28.1×10^-24cm³; (17)Surface Tension: 47.7 dyne/cm; (18)Density: 1.24 g/cm³; (19)Flash Point: 201.1 °C; (20)Enthalpy of Vaporization: 67.67 kJ/mol; (21)Boiling Point: 422.5 °C at 760 mmHg; (22)Vapour Pressure: 2.39E-07 mmHg at 25°C.

Preparation of 4H-1-Benzopyran-4-one,5-methoxy-2-phenyl-: this chemical can be prepared by 1-(2-Hydroxy-4-methoxyphenyl)-3-phenylpropyn-1-one by heating. This reaction will need reagent K₂CO₃ and solvent acetone with the reaction time of 1 hour. The yield is about 80%.

Uses of 4H-1-Benzopyran-4-one,5-methoxy-2-phenyl-: it can be used to produce 4,5-dimethoxy-2-phenyl-chromenylium; perchlorate at the temperature of 50 °C. It will need reagent HClO₄ with the reaction time of 10 hours. The yield is about 32%.

When you are using this chemical, please be cautious about it as the following:
It is irritating to eyes, respiratory system and skin. In case of contact with eyes, you should rinse immediately with plenty of water and seek medical advice. When using it, you need wear suitable protective clothing, gloves and eye/face protection.

You can still convert the following datas into molecular structure:
(1)Canonical SMILES: COC1=CC=CC2=C1C(=O)C=C(O2)C3=CC=CC=C3
(2)InChI: InChI=1S/C16H12O3/c1-18-13-8-5-9-14-16(13)12(17)10-15(19-14)11-6-3-2-4-7-11/h2-10H,1H3
(3)InChIKey: XRQSPUXANRGDAV-UHFFFAOYSA-N