Benzonaphthalene derivatives, a process for their preparation and their use in therapeutic and cosmetic compositions

A process for the treatment of a dermatologic, rheumatismal, respiratory or ophtalmologic disease comprising administering to a person suffering from said disease an effective amount of a composition containing, in a pharmaceutically acceptable vehicle, as the active ingredient thereof a benzonaphthalene compound of the formula ##STR11## wherein R.sub.1 represents ##STR12## or (ii) --CH.sub.2 OH, R.sub.6 represents ##STR13## or OR.sub.7 wherein R.sub.7 represents hydrogen, alkyl having 1-20 carbon atoms, monohydroxyalkyl or polyhydroxyalkyl, r' and r" represent hydrogen, lower alkyl, mono or polyhydroxyalkyl aryl or a residue of an amino acid, glucosamine, galactosamine or mannosamine, or together form a heterocycle selected from the group consisting of piperidino, piperazino, morpholino and pyrrolidino,

• R.sub.2 represents hydrogen, branched or straight chain alkyl having 1-15 carbon atoms, alkoxy having 1-4 carbon atoms or a cycloaliphatic radical,
• R.sub.3 represents hydrogen, hydroxy, branched or straight chain alkyl having 1-4 carbon atoms, alkoxy having 1-10 carbon atoms, a cycloaliphatic radical selected from the group consisting of 1-methylcyclohexyl and 1-adamantyl, a thiocycloaliphatic radical, or --O--Si(CH.sub.3).sub.2 --R.sub.8 wherein R.sub.8 represents linear or branched alkyl,
• R.sub.4 and R.sub.5 each independently represent hydrogen, lower alkyl or lower acyloxy.
• or a salt thereof.