| 摘要 |
NEW MATERIAL:A chalcone derivative shown by the formula I (R1 is H, or OH3; R2 is 2-24C aliphatic hydrocarbon group). EXAMPLE:4-Methoxy-4'-methyl-branched isostearoyloxychalcone. USE:An ultraviolet light absorber. Protecting effectively the skin from ultraviolet rays having 400-320nm long wavelength. It is blended with a base for cosmetic, and useful as oil for preventing sunburn oil, lotion, skin care cream agent, etc. PREPARATION:A 4-methoxybenzadehyde shown by the formula II is condensed with 4-hydroxyacetophenone shown by the formula III to give an 4-alkoxy-4'-hydroxychalcone shown by the formula IV, which is reacted with an acid chloride shown by the formula V in the presence of a nonnucleophilic basic catalyst or a carboxylic acid anhydride shown by the formula VI and a catalyst such as pyridine, etc. to give a compound shown by the formula I .
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