| 摘要 |
The composition contains as active constituent a dicarboxylic acid containing between 7 and 13 carbon atoms or one of its derivatives with at least one reducing functional group in the molecule. For the preparation of the active constituent in the form of a mercaptoderivative, the bromine derivative is prepared with a number of substituting bromine atoms equal to the number of mercaptogroups to be inserted, and the bromine derivative is reacted with thiourea and ethyl alcohol to form the alkylthiouronic salt which, by saponification, forms the corresponding mercaptoderivative. The composition according to the present invention can be applied topically in the form of creams, pomades, ointments and lotions. The compositions according to the present invention have proved capable in particular of inhibiting the formation of the cutaneous pigment (melanin) by blocking the dopa-tyrosinase reaction by a competitive mechanism. |
