| 摘要 |
The invention relates to a process for the preparation of a 2-dimethyl phenyl benzofuran of the general formula <FORM:1114030/C2/1> by (1) heating a ketone of a general formula <FORM:1114030/C2/2> with an acid catalyst to effect rearrangement, e.g. polyphosphoric acid or (2) decarboxylating and dehydrating an acid of the general formula <FORM:1114030/C2/3> in which R1, R2 and R3 are hydrogen or one of them is a methyl group. Compounds claimed per se are 2-(2,4-dimethylphenyl)-benzofuran, 2 - (2,4 - dimethylphenyl) - 5 - methyl - benzofuran, 2 - (2,4 - dimethylphenyl) - 6 - methyl-benzofuran, 2 - (2,4 - dimethylphenyl) - 7 - methyl-benzofuran.ALSO:A cosmetic composition capable of absorbing ultra-violet radiation comprises one or more compounds of a general formula: <FORM:1114030/A5-A6/1> in which R1, R2 and R3 are hydrogen or one of them is a methyl group in association with a cosmetic carrier. Many carriers are specified. The compositions may also contain one or more other UV radiation absorbers, such as the sodium salt of 2 - phenylbenzimidazole - 5 - sulphonic acid, the sodium salt of 3,4 - dimethylphenylglyoxylic acid, 4 - phenylbenzophenone or 4 - phenyl - benzophenone - 2/sv - carboxylic acid isooctyl ester. Other additives, such as perfumes, preserving agents or physiologically acceptable dyes, may also be added. Examples are given of compositions in the form of oils, creams, milk, aerosol and lipsticks. |
