Alpha-lipoic acid derivatives and their use in drug preparation

An enantiomer R of a compound of formula (I):

• wherein
• X is —NH—R1 , or
• R1 is —(CH2)n—R2,
• R2 is a linear, branched or cyclic C1-C6 aliphatic group, —O—(CH2)n—CH3, —NH—CO—(CH2)n—CH3, a 5- or 6-membered aliphatic or aromatic ring optionally comprising a heteroatom, a 5- or 6-membered aromatic ring substituted by one or two substituents, said substituents being selected from the group consisting of —OH, —O(alkyl C1-C3) and —OCO(alkyl C1-C3), or
• R3 is H or a C1-C3 aliphatic group and R4 is a linear C1-C3 or a branched C3-C12 aliphatic group, or R3 is a C1-C3 aliphatic group and R4 is a linear C1-C12 aliphatic group,
• Y is O, CH—(CH2)n—CH3 or N(CO)(CH2)n—CH3, and
• n is an integer from 0 to 6.

A method to treat diabetes, diabetic neuropathy, obesity and pathologies related thereto in an individual, the method comprising

• administering to the individual an effective amount of an enantiomer R of the compound of formula I:
• wherein
• X is —NH—R1 or
• R1 is —(CH2)n—R2, wherein
• R2 is a linear C1-C3 aliphatic group and n is an integer from 0 to 2, or
• R2 is a branched or cyclic C1-C6 aliphatic group, —O—(CH2)n—CH3, —NH—CO—(CH2)n—CH3 and n is an integer from 0 to 6, or
• R2 is a 5- or 6-membered aliphatic or aromatic ring optionally comprising a heteroatom, or a 5- or 6-membered aromatic ring substituted by one or two substituents, said substituents being selected from the group consisting of —OH, —O(alkyl C1-C3) and —OCO(alkyl C1-C3), or
• n is an integer from 0 to 6, and
• Y is O, CH—(CH2)n—CH3 or N(CO)(CH2)n—CH3, and
• R3 is H or a C1-C3 aliphatic group and R4 is a branched C3-C12 aliphatic group, wherein at least a branch is in alpha-position, or R3 is a C1-C3 aliphatic group and R4 is a linear C1-C6 aliphatic group.

Method of treating tumours in an individual, the method comprising

• administering to the individual in an amount effective to induce apoptosis of tumour cells, an enantiomer R of a compound of formula I:
• wherein
• X is —NH—R1 or
• R1 is a linear C6-C12 aliphatic group, or is a branched C5-C12 aliphatic group, wherein at least an ethyl branch is in alpha-position,
• Y is O, CH—(CH2)n—CH3 or N(CO)(CH2)n—CH3, and
• n is an integer from 0 to 6.