Liver protection or treatment agents comprising asiatic acid derivatives as the active component

A method of treating or preventing hepatotoxicity, said method comprising administering to a patient in need of such treatment, a therapeutically effective amount of a compound, or a pharmaceutically acceptable salt or ester thereof, represented by Formula 1

• wherein:
• R1 is chosen from —H, a hydroxy group, a hydroxy group protected by an acetyl or benzoyl group, a methyl group, an ethyl group, a methoxy group, an ethoxy group, a vinyl group, an ethinyl group, a cyano group, an azide group, an ethoxymethyloxy group, an octyloxymethyloxy group, a methanesulfonyloxy group, a phenylthio group and a (methylthio)thiocarbonyloxy group, or
• R1 and R2 taken together may form an oxo group;
• R2 is chosen from —H, a methoxy group, an ethoxy group, a hydroxy group and a hydroxy group protected by an acetyl or benzoyl group, or
• R2 and R4 taken together may form an epoxy group;
• R3 is chosen from —H, a vinyl group, a methyl group, an ethyl group, a hydroxy group and a hydroxy group protected by an acetyl or benzoyl group or
• R3 and R4 taken together may form an oxo group;
• R4 is chosen from —H, a methyl group, an ethyl group, a vinyl group, a hydroxy group and a hydroxy group protected by an acetyl or benzoyl group;
• R5 is chosen from a methyl group, a hydroxymethyl group wherein the hydroxy group may be protected by an acetyl or benzoyl group, a t-butyldimethylsilyloxymethyl group, a carboxylic group, a carboxylic ester moiety, a carboxylic amide moiety and an aldehyde group, or
• R4 and R5 taken together may form —OCR6R7OCH2—, wherein
• R6 is chosen from —H, a lower alkyl group having 1-4 carbon atoms and a phenyl group;
• R7 is chosen from —H, a lower alkyl group having 1-4 carbon atoms and a phenyl group, or
• R6 and R7 taken together may form —(CH2)5;
• R8 is chosen from —H and a methyl group;
• R9 is chosen from —CH2COOR and —COOR, wherein
• R is chosen from —H, a lower alkyl group having 1-4 carbon atoms, a 2-tetrahydropyranyl group, CH(OR11)R10, CH(OR13)CH2R12, wherein
• R10 is chosen from —H, a methyl group and an ethyl group;
• R11 is chosen from a lower alkyl group having 1-4 carbon atoms, an octyl group, a benzyl group, a methoxymethyl group and a methoxyethyl group;
• R12 is chosen from —H, a methyl group and an ethyl group;
• and
• R13 is chosen from a methyl group and an ethyl group, or
• R12 and R13 taken together may form —CH2CH2CH2—,
• a glucosyl or a rhamnosyl group, wherein the hydroxy group may be protected by an acetyl or benzoyl group,
• a hydroxymethyl group wherein the hydroxy group may be protected by an acetyl or a benzoyl group, a methanesulfonyloxymethyl group and a cyanomethyl group;
• and
• R14 and R15 are independently —H, or R14 and R,5 taken together form an oxo group, with the provisos that:
• when R1 and R4 are hydroxy, R2 and R3 are —H, R5 is hydroxymethyl and R8 is methyl,
• R is not —H or methyl and R10 is not —H;
• and
• when R1 is —OH, R2 is —H, R3 or R4 form with R5 —OC(R6)(R7)OCH2—, and R6 is methyl,
• R is not methyl,
• and a pharmaceutically acceptable carrier.