THE INVENTION RELATES TO DERIVATIVES OF MORPHINE-6-GLUCURONIDE HAVING FORMULA (I) WHEREIN R1 IS A 5-MEMBERED HETEROAROMATIC GROUP OPTIONALLY SUBSTITUTED BY ONE OR MORE SUBSTITUENTS SELECTED FROM AMONG HALOGEN ATOMS AND (C1-C4)ALKYL, HALOGEN, HYDROXYL, HALO(C1-C4)ALKYL, HALO(C1-C4)ALKYLOXY, (C1-C4)ALKYLOXY, ARYL(C1-C4)ALKYL AND ARYL GROUPS, SAID ARYL GROUP BEING OPTIONALLY SUBSTITUTED BY ONE OR MORE GROUPS SELECTED FROM AMONG (C1-C4)ALKYL, HALO(C1-C4)ALKYL, HYDROXYL AND (C1-C4)ALKYLOXY GROUPS, IN THE FORM OF A BASE OR ACID ADDITION SALT, AS WELL AS IN HYDRATE OR SOLVATE FORM. THE INVENTION ALSO RELATES TO THE PREPARATION METHOD THEREOF AND TO THE USE OF SAME IN THERAPEUTICS.
