Degussa Aktiengesellschaft

Energieversorgung Weser-ems Ag

Jurgen Martens

Axel Kleemann

Horst Weigel

Horst Bethge

Karlheinz Drauz

Friedrich Bittner

Paul Scherberich

Herbert Tanner

Friedhelm Geiger

Manfred Spindler

Klaus Deller

Werner Schwarze

Wolfgang Leuchtenberger

Franz Effenberger

Marc Samson

Bernd Lehmann

Kurt Gunther

Harald Peterson

Werner Harms

Regina Steigerwald

Uwe Kramer

Eberhard Busker

Hans G Koban

Maren Schickedanz

Halogen thiophene carboxylic acid derivatives of the General Formula ##STR1## in which Hal signifies chlorine or bromine, n the number 2 or 3, * signifies either an enantiomer or a racemate in the case of different R.sup.2 and R.sup.3 groups, R.sup.1 stands for hydrogen or an alkyl group, R.sup.2 stands for hydrogen, an alkyl group which can optionally be substituted by hydroxy-, carboxy-, alkoxy- or alkoxycarbonyl, mercapto- or alkylmercapto- or benzylmercapto, for an aryl group or aralkyl group, wherein the ring system can optionally be substituted with fluorine, chlorine or bromine atoms, for a cycloalkyl group or a cycloalkyl-methyl group, R.sup.3 stands for hydrogen, an alkyl group, an alkenyl or alkynyl group or, optionally, R.sup.1 and R.sup.3 or R.sup.2 and R.sup.3 together can form an alkylene bridge in which one CH.sup.2 unit can optionally be substituted by NR.sup.1, O or S, Y signifies OH, OR.sup.4 or NR.sup.5 R.sup.6, in which R.sup.4 stands for an alkyl group whose H atoms are optionally replaced entirely or partially by halogen atoms, R.sup.5 signifies hydrogen, an alkyl group, hydroxy- or an alkoxy group, R.sup.6 signifies hydrogen, an alkyl group, a phenyl group or a cycloalkyl group or, optionally, R.sup.5 and R.sup.6 can form a ring with inclusion of the nitrogen atom and, optionally, of a further heteroatom. In addition, a method of their production is described. Compounds of General Formula I can be used in the form of plant protection products with suitable carrier materials.

Compounds for combating plant disease

A method for the removal of water or aqueous liquids from the sump of an underground cavity, especially a cavern, is based on providing a process in which a water-miscible organic liquid is added to the sump, and then the mixture formed in this way is extracted from the cavity.

Method for the removal of aqueous liquids from the sump of an

Thin-layer chromatography is employed to separate enantiomers of the general formula, ##STR1## in which C* represents an asymmetric center and the substituents R.sup.1, R.sup.2, and R.sup.3 are such that they supply the structural element ##STR2## for .alpha.-amino- or .alpha.-iminocarboxylic acids, particularly the well-known .alpha.-amino- or .alpha.-iminocarboxylic or for derivatives of such carboxylic acids, either of which contains no free thiol groups. In the thin-layer chromatographic separation operation a TLC plate is used which is coated with silica gel hydrophobicized by a silane derivative and which is further impregnated with an ionic compound of a divalent transition metal and a chiral selector. The mobile phase employed is a ternary mixture of a water-miscible alkanol, such as methanol, water, and acetonitrile, or a quaternary mixture of the latter ternary mixture to which a water-miscible cyclic ether, such as tetrahydrofuran, has been added.

Thin-layer chromatographic method for the separation of enantiomers

Pure L-leucine is obtained from an aminoacid mixture which contains at least 45 weight percent L-leucine, at most 40 weight percent L-isoleucine and at most 25 weight percent of other aminoacids by acetylating the mixture, precipitating the acetylation product by acidification, subjecting the acetylation product to a saponification by an L-aminoacid acylate until 30 to 95% of the N-acetyl-L-leucine employed is saponified and isolating the L-leucine from the saponification mixture.

Process for obtaining pure L-leucine

The separation of L-leucine and L-isoleucine in aminoacid mixtures containing at least 30 weight percent L-leucine, at most 70 weight percent L-isoleucine and at most 40 weight percent of other aminoacids is accomplished by acetylating the mixture, precipitating the acetylation product by acidification, subjecting the aqueous solution to a saponification by an L-aminoacid acylase until 25 to 95% of the N-acetyl-L-leucine is saponified, crystallizing pure L-leucine from the saponification mixture and separating it off, isolating N-acetyl-L-isoleucine from the mother liquor and saponifying it in known manner to the free aminoacid and isolating the free aminoacid.

Process for the separation of L-leucine and L-isoleucine

The subject matter of the invention is a process for the recovery of S-(carboxymethyl)-(R)-cysteine and S-(carboxymethyl)-(S)-cysteine from a mixture of the two enantiomers. The mixture to be separated is dissolved in water in the presence of sufficient ammonia that the ammonium salt solution formed has a pH between 6 and 9. Then there is brought about in the solution of ammonium salt a state of supersaturation by the addition of seeding crystals of the ammonium salt of one of the two enantiomers, insofar as the starting material contains one of the two enantiomers in excess, the ammonium salt of this enantiomer, the ammonium salt of one of the two enantiomers is brought to crystallization and separated off. Subsequently by addition of seeding crystals of the ammonium salt of the other enantiomers to the remaining mother liquor the ammonium salt of this enantiomer is likewise brought to crystallization and separated off. Finally the respective S-(carboxymethyl)-cysteine is set free from the two ammonium salts.

Process for the recovery of S-(carboxymethyl)-(R)-cysteine and

There are prepared 1-amino-2-mercapto-2-methylpropyl phosphonic acid or 1-amino-2-mercapto-2-methylpropyl alkylphosphinic acids of the formula ##STR1## in which Y is hydroxy or an alkyl group by reacting thiazoline-(3) with a phosphonic acid dialkyl ester or an alkylphosphinic acid alkyl ester and then hydrolytically splitting the thiazolidinyl phosphonic acid dialkyl ester or thiazolidinyl alkylphosphinic acid alkyl ester. The thiazolidinyl compounds are new compounds. The 1-amino-2-mercapto-2-methylpropyl phosphonic acid and the 1-amino-2-mercapto-2-methylpropyl alkylphosphinic acids are needed for pharmaceutical purposes.

Process for the production of substituted phosphonic and phosphinic

There are prepared specific .alpha.-aminocarboxylic acids or their methyl, ethyl, or benzyl esters in which the .alpha.-amino group is substituted by a 3-cyanopropanoyl group. The compounds are useful for producing the corresponding derivatives of 4-aminobutyramide ('Gabamide') by catalytic hydrogenation of the cyano group.

N.alpha.-(3-Cyanopropanoyl)-aminocarboxylic acid derivatives and their

The invention is directed to optically active proline derivative of the general formula: ##STR1## in which X is a hydrogen atom or a hydroxyl group and R is a hydrogen atom, an unsubstituted or alkyl group substituted phenyl group or a straight chain or branched alkyl group having 1 to 20 carbon atoms and a process for its production by reacting an enantiomerically pure proline or 4-hydroxy-proline as a solution in an alkanol having 1 to 4 carbon atoms with 0.9 to 2 times the molar amount of an alkali metal alcoholate corresponding to the alkanol and 1 to 3 times the molar amount of an epoxide of the general formula ##STR2## in which R is as defined above. The optically active proline derivative of general formula (I) can be used in the form of metal ion chelate complexes as the chiral stationary phase in the separation of enantiomers by means of liquid chromatography.

Optically active proline derivative, process for its production and use

L-proline is produced from the methyl or ethyl ester of L-pyroglutamic acid by reacting this with at least twice the molar amount of phosgene to form the corresponding 1-chlorocarbonyl-5,5-dichloroproline ester, producing the corresponding 2-chloro-1-chlorocarbonyl-pyrrolin-(2)-carboxylic acid ester-(5) therefrom by splitting off hydrogen chloride, catalytically hydrogenating the pyrrolin-(2) compound to the corresponding N-chlorocarbonyl-proline ester and hydrolyzing the latter with acid to form L-proline.

Process for the production of L-proline

Aqueous solutions of sodium salts of .alpha.-aminocarboxylic acids practically free of foreign salts are produced by saponifying the corresponding hydantoin at a temperature between 110.degree. C. and 180.degree. C. with a mixture, in each case based on the hydantoin, of 1 equivalent of sodium hydroxide and 2 equivalents of calcium oxide or hydroxide, separating off the precipitated calcium carbonate after the end of the saponification and concentrating the aqueous sodium salt solution remaining to drive off the ammonia contained therein.

Process for the production of aqueous solutions of sodium salts of .alpha.-

To separate the racemate (R,S)-cysteine, the racemate is condensed in an inert solvent with an enantiomerically enantiomeric monosaccharide of the group of aldoses having 4 to 7 carbon atoms to form the corresponding 2-substituted thiazolidin-4-carboxylic acid and the mixture of diastereomers obtained separated from each other. Subsequently, the isolated unitary diastereomers are reacted in an inert solvent with a carbonyl reagent to split the ring and the enantiomerically pure cysteine in each case is isolated as such or as the corresponding cystine.

Process for the separation of the racemate (R,S)-cysteine

.alpha.-(3-Cyano-propanoyl)-aminocarboxylic acid derivatives

There is described the resolution of the racemate (1RS,2SR)-2-amino-1-phenyl-propan-1-ol. It is carried out by means of the optical isomers of S-(carboxymethyl)-cysteine.

Process for the resolution of the racemate

There is described the resolution of the racemate S-(carboxymethyl)-(RS)-cysteine. It is carried out by means of the optical isomers of 2-amino-1-phenyl-propan-1-ol. This process makes it possible to obtain in a simple manner S-(carboxymethyl)-(R)-cysteine which is important for pharmaceutical purposes and is made from synthetically produced cysteine.

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Alzenau, Germany

Jurgen Martens