Esters derived from substituted phennyl-cyclohexyl compounds

A Compound of formula (I):

• R2 is:
• OH;
• R3 is:
• H;
• or R2 and R3 together form a double bond;
• R4 is:
• H or C1-C2 alkyl;
• R5 is:
• H, NH2, NH—R11 or O—R11;
• R6 is:
• H, CO—R11, O—R11 or halogen;
• R7 is:
• H, C1-C5 alkyl, C2-C5 O-alkenyl, phenyl, or R6 and R7 are —CH═CR12—CR13═CH—, forming an unsubstituted or substituted with R12 or R13 condensed aromatic ring;
• R8 is:
• OH, —O—CO—N(CH3)2 or NH—R11;
• R11 is:
• phenyl;
• phenyl unsubstituted or substituted by 1 or more of the following substituents:
• halogen (Cl, Br, I), NO2, C1-C6 alkyl, C2-C6 alkenyl, OH, or NH2;
• R12 and R13 are:
• H, or C1-C3 O-alkyl, whether equal or different;
• its salts and optical isomers.