A bicyclic naphthalenic compound has the formula ##STR1## wherein A represents methylene or dimethylene, substituted or not by lower alkyl,R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represent hydrogen or lower alkyl, orR.sub.1 and R.sub.3 taken together form a methylene or dimethylene bridge when A represents dimethylene,R' represents hydrogen, OH, alkoxy having 1-4 carbon atoms, acyloxy having 1-4 carbon atoms or amino,R" represents hydrogen or alkoxy having 1-4 carbon atoms, orr' and R" taken together form an oxo, methano or hydroxyimino group,R represents --CH.sub.2 OH or --COR.sub.5,R.sub.5 represents hydrogen, --OR.sub.6 or ##STR2## R.sub.6 represents hydrogen, alkyl having 1-20 carbon atoms, monohydroxyalkyl, polyhydroxyalkyl, aryl or aralkyl optionally substituted, the residue of a sugar or ##STR3## p is 1, 2 or 3, and r' and r", each independently, represent hydrogen, lower alkyl, monohydroxyalkyl optionally interrupted by a heteroatom, polyhydroxyalkyl, aryl or benzyl optionally substituted, the residue of an amino acid, an aminoester or an aminated sugar, or r' and r" together form with the nitrogen atom to which they are attached, a heterocycle substituted or not, and the salts of said compounds of formula (I) or the optional isomers thereof.