1. Basic Identification Information

Parameter	English Specification/Value
IUPAC Name	1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione (also: 4-tert-butyl-4'-methoxydibenzoylmethane)
Common Name(s)	Avobenzone; Parsol 1789; Eusolex 9020; Escalol 517; Neo Heliopan 357; Butyl Methoxydibenzoylmethane (BMDBM)
CAS Registry Number	70356-09-1
EC/EINECS Number	274-576-0
Molecular Formula	C₂₀H₂₂O₃
Molecular Weight	310.39 g/mol
Chemical Class	Dibenzoylmethane derivative; oil-soluble organic UVA filter; sunscreen agent; photoprotective ingredient

2. Physicochemical Properties

Property Category	Specific Parameter	Specification/Value
Structural Features	Functional Groups	β-diketone system (enol-keto tautomerism); tert-butyl group; methoxy group; two benzoyl groups
Physical Appearance	State & Color	Pale yellow crystalline powder; slight characteristic odor
	Melting Point	81-84 °C (lit.)
	Boiling Point	Decomposes before boiling (decomposes >150 °C)
	Density (25 °C)	1.10 g/cm³ (crystalline form)
Solubility	Oil Solubility	Soluble in ethanol, isopropanol, acetone, ethyl acetate, and cosmetic oils (100+ g/100 mL)