Abstract: The invention relates to a method for producing pure racemic, R- or S-thioctic acid or mixtures thereof by reacting 6,8-disubstituted octanoic acid or their salts or esters with sulfides, sulfur or sulfites.

Abstract: The invention relates to a method for the production of (R)- or (S)-8-chloro-6-hydroxyoctanoic acid alkyl esters of the general formula (R)-II or (S)-II in which R has the meaning C1-4-alkyl, from 8-chloro-6-oxooctanoic acid alkyl esters of the general formula I in which R has the above meaning, by enzymatic reduction using alcohol dehydrogenases, such as Lactobacillus brevis or Thermoanaerobium brokii, in the presence of cofactor regeneration systems. The resulting (R)- and (S)-8-chloro-6-hydroxyoctanoic acid esters can be converted in a known manner into (R)-?-lipoic acid and (S)-?-lipoic acid, respectively.

Abstract: The invention relates to new modifications of the trometamol salt of R-thioctic acid of the formula I, processes for their production, pharmaceutical preparations containing these modifications, and their medical application.

Abstract: The invention relates to a method for producing pure racemic, R- or S-thioctic acid or mixtures thereof by reacting 6,8-disubstituted octanoic acid or their salts or esters with sulfides, sulfur or sulfites.

Abstract: The invention relates to a method for the production of (R)- or (S)-8-chloro-6-hydroxyoctanoic acid alkyl esters of the general formula (R)-II or (S)-II in which R has the meaning C1-4-alkyl, from 8-chloro-6-oxooctanoic acid alkyl esters of the general formula I in which R has the above meaning, by enzymatic reduction using alcohol dehydrogenases, such as Lactobacillus brevis or Thermoanaerobium brokii, in the presence of cofactor regeneration systems. The resulting (R)- and (S)-8-chloro-6-hydroxyoctanoic acid esters can be converted in a known manner into (R)-?-lipoic acid and (S)-?-lipoic acid, respectively.

Abstract: The invention relates to new modifications of the trometamol salt of R-thioctic acid of the formula I, processes for their production, pharmaceutical preparations containing these modifications, and their medical application.

Abstract: The invention relates to new modifications of the trometamol salt of R-thioctic acid of the formula I, processes for their production, pharmaceutical preparations containing these modifications, and their medical application.

Abstract: The invention relates to new modifications of the trometamol salt of R-thioctic acid of the formula I, 1

Abstract: The invention relates to new modifications of the trometamol salt of R-thioctic acid of the formula I, 1

Abstract: The invention relates to a process for the preparation of compounds of the general formula I in which R1 and R2 are identical or different and are a C1-C20-alkyl group, C3-C12-cycloalkyl group, C7-C12-aralkyl group or a mono- or binuclear aryl group, in which a ketone of the formula III or IV in which R1 and R2 have the above meaning, is asymmetrically hydrogenated.

Abstract: The invention relates to a process for the preparation of compounds of the general formula I ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are a C.sub.1 -C.sub.20 -alkyl group, C.sub.3 -C.sub.12 -cycloalkyl group, C.sub.7 -C.sub.12 -aralkyl group or a mono- or binuclear aryl group, in which a ketone of the formula III or IV ##STR2## in which R.sup.1 and R.sup.2 have the above meaning, is asymmetrically hydrogenated.

Abstract: The invention is relative to a thioctic acid with a predominant amount of an enantiomer and a novel modification, in the case of which the X-ray powder diffractograms show a characteristic reflex in the range of 23.4 to 22.7.degree. 2 theta(Cu) which shifts in the direction of the smaller angular values as the enantiomer content increases.

Abstract: The invention relates to (+) and (-)-8-halogen-6-hydroxy-octanoic acid enantiomers wherein the halogen is Cl, Br, or I, and their respective preparatory processes.

Abstract: The invention relates to (+) and (-)-8-halogen-6-hydroxy-octanoic acid enantiomers wherein the halogen is Cl, Br, or I, and their respective preparatory processes.

Abstract: The synthesis of pure enantiomers of 8-chloro-6-sulfonyloxy-octanoic acids and their alkyl esters and of pure enantiomers of 6,8-dichloro-octanoic acid and its alkyl esters as intermediates for the synthesis of the enantiomers of .alpha.-liponic acid as well as a method for converting the two enantiomers of 8-chloro-6-hydroxy-octanoic acid into an enantiomer of .alpha.-liponic acid.

Abstract: A compound or its tautomer of Formula I, ##STR1## wherein R.sup.1 is hydrogen, a 6-methyl, 6-fluoro, 6-chloro, 6-bromo, or 6,7-dimethoxy residue,R.sup.2 is hydrogen, or a methyl residue,and n is 1 or 2,and tautomers and their pharmaceutically acceptable alkali, or ammonium salts.