Abstract: New genes containing a DNA sequence coding for hydroxynitrile lyase, which genes can be prepared via a primer combination based on the DNA sequence of the 5?-region of the mdl genes from the Prunus serotina and from Prunus amygdalus and/or a primer 2 based on the 3?-region of the DNA sequences of one of the hydroxynitrile lyase isoenzymes from Prunus serotina or from Prunus amygdalus, subsequent amplification with a DNA polymerase using a DNA from organisms, containing genes coding for hydroxynitrile lyase, as templates and cloning, and also recombinant proteins which can be prepared in suitable host cells by heterologous expression of the DNA sequence of said HNL genes, and proteins and fusion proteins derived therefrom and use of said proteins for preparing (R)- or (S)-cyanohydrins.

Abstract: A process for preparing enantiomer-enriched heterocyclic (R)- and (S)-cyanohydrins of the formula (I), where R1, R2, R3, R4 independently of one another are H, an unsubstituted or substituted C1–C24-alkyl, alkenyl or alkynyl radical, where one or more carbon atoms in the chain can be replaced by an oxygen atom, a nitrogen atom, a sulfur atom, an SO or an SO2 group, an unsubstituted or substituted aryl or heteroaryl radical or heterocyclic radical or halogen, hydroxyl, NR5R6, acetyl, oxo, C1–C6-carbalkoxy, C1–C6-carbalkoxyamino, COOR7, cyano, amide, benzoylamino or NO2, R5 and R6 are H, C1–C6-alkyl radical, phenyl radical, benzyl radical or COOR7, or together form a C2–C8-alkylene or heteroalkylene radical, R7 is H or C1–C6-alkyl, n is 0, 1, 2 or 3, X, Y and Z can be an unsubstituted or substituted carbon atom or a radical selected from the group consisting of N, O, S or NR5R6, where R5 and R6 are as defined above, SO or SO2, and at least one of the radicals X, Y and Z is not a carbon atom, where the compo

Abstract: A process for preparing protected, enantiomer-enriched cyanohydrins of the formula where R1 and R2 independently of one another can be an unsubstituted, monosubstituted or polysubstituted C1-C20-alkyl, C5-C20-aryl, C5-C20-heteroaryl, C5-C20-alkaryl, C5-C20-alkylheteroaryl or C5-C20-aralkyl radical or an unsubstituted, monosubstituted or polysubstituted C5-C20-heterocycle, or C5-C20-alkylheterocycle or together can be an unsubstituted or substituted C4-C20-alkylene radical, which can contain one or more heteroatoms in the chain, or one of the radicals is hydrogen, and R3 can be an unsubstituted or substituted C1-C20-alkyl, C5-C20-aryl or C5-C20-heteroaryl radical, by reacting an aldehyde or ketone of the formula where R1 and R2 are defined as above, in the presence of an (R)- or (S)-hydroxynitrile lyase in an organic, aqueous or 2-phase system or in emulsion at a temperature of ?5 to +40° C. with a carbonic ester nitrile of the formula where R3 is defined as above.

Abstract: New genes containing a DNA sequence coding for hydroxynitrile lyase, which genes can be prepared via a primer combination based on the DNA sequence of the 5?-region of the mdl genes from the Prunus serotina and from Prunus amygdalus and/or a primer 2 based on the 3?-region of the DNA sequences of one of the hydroxynitrile lyase isoenzymes from Prunus serotina or from Prunus amygdalus, subsequent amplification with a DNA polymerase using a DNA from organisms, containing genes coding for hydroxynitrile lyase, as templates and cloning, and also recombinant proteins which can be prepared in suitable host cells by heterologous expression of the DNA sequence of said HNL genes, and proteins and fusion proteins derived therefrom and use of said proteins for preparing (R)- or (S)-cyanohydrins.

Abstract: New genes containing a DNA sequence coding for hydroxynitrile lyase, which genes can be prepared via a primer combination based on the DNA sequence of the 5?-region of the mdl genes from Prunus serotina and from Prunus amygdalus and/or a primer 2 based on the 3?-region of the DNA sequences of one of the hydroxynitrile lyase isoenzymes from Prunus serotina or from Prunus amygdalus, subsequent amplification with a DNA polymerase using a DNA from organisms, containing genes coding for hydroxynitrile lyase, as templates and cloning, and also recombinant proteins which can be prepared in suitable host cells by heterologous expression of the DNA sequence of said HNL genes, and proteins and fusion proteins derived therefrom and use of said proteins for preparing (R)- or (S)-cyanohydrins.

Abstract: A process for the preparation of chiral &agr;-hydroxycarboxylic acids: in which R1 is optionally halogen substituted C1-C2-alkyl and R2 is optionally halogen substituted C2-C3-alkyl from a compound: in which R′2 is optionally halogen substituted C2-C3-alkylene, m is 0 or 1 and R is optionally substituted alkyl, aryl, heteroaryl or heterocyclyl and X can be oxygen, sulfur, sulfinyl, sulfonyl, imino, C1-C6-alkylimino, xanthate, silyl, or, if m is equal to 0, halogen, which is reacted in the presence of a cyanide group donor to give the corresponding (R)- or (S)-cyanohydrin or its racemate: which then is converted by means of acidic hydrolysis into an acid: or its racemate, and by cleavage of the group: (R)m-X  (V), and optional resolution, whereby the desired chiral &agr;-hydroxycarboxylic acid of the formula (I) is obtained.

Abstract: The invention relates to the production of (R)-enantiomeric, optically active cyanohydrins by reacting an aldehyde or a ketone with a cyanide group donor in the presence of (R) oxynitrilase, wherein a reaction mixture comprising a) an aldehyde or a ketone dissolved in an organic solvent; said organic solvent is immiscible or only slightly miscible with water, b) any aqueous R)-oxynitrilase solution and c) a cyanide group donor is stirred in such away that an emulsion is formed which remains intact until the end of the enzymatic reaction. After the enzymatic reaction has terminated, the (R)-cyanohydrin is isolated from the reaction mixture.

Abstract: Process for preparing enantiomer-enriched cyanohydrins in which an acetal or ketal of the formula (I) is reacted 1

Abstract: A process for preparing protected, enantiomer-enriched cyanohydrins of the formula 1

Abstract: A process for preparing enantiomer-enriched heterocyclic (R)- and (S)-cyanohydrins of the formula (I), 1

Abstract: New genes containing a DNA sequence coding for hydroxynitrile lyase, which genes can be prepared via a primer combination based on the DNA sequence of of the 5′-region of the mdl genes from Prunus serotina and from Prunus amygdalus and/or a primer 2 based on the 3′-region of the DNA sequences of one of the hydroxynitrile lyase isoenzymes from Prunus serotina or from Prunus amygdalus, subsequent amplification with a DNA polymerase using a DNA from organisms, containing genes coding for hydroxynitrile lyase, as templates and cloning, and also recombinant proteins which can be prepared in suitable host cells by heterologous expression of the DNA sequence of said HNL genes, and proteins and fusion proteins derived therefrom and use of said proteins for preparing (R)- or (S)-cyanohydrins.

Abstract: A process for the preparation of chiral &agr;-hydroxycarboxylic acids: 1

Abstract: A process for the preparation of enantiomer-enriched aminofuranones and hydroxyfuranones in which an enantiomer-enriched cyanohydrin is acylated by an acylating agent, then cyclized at 40 to 90° C. in the presence of zinc or a zinc compound to the corresponding enantiomer-enriched aminofuranone, which is converted where appropriate by acid hydrolysis into the corresponding enantiomer-enriched hydroxyfuranone.

Abstract: An enantioselective process for the preparation of the (S)-enantiomer of an optically active cyanohydrin by reaction of an aldehyde or of a ketone with a cyanide group donor, in which the aldehyde or the ketone is reacted with a cyanide group donor in an organic diluent in the presence of a recombinant (S)-hydroxynitrile lyase from Hevea brasiliensis and the (S)-cyanohydrin formed is isolated from the reaction mixture.

Abstract: Process for the preparation of the (S)-enantiomers of optically active cyanohydrins, in which a reaction mixture of a) an aldehyde or ketone dissolved in an organic, water-immiscible or slightly miscible diluent, b) an aqueous (S)-hydroxynitrile lyase solution and c) a cyanide group donor is stirred in such a way that an emulsion is formed which is maintained up to the end of the reaction by stirring.

Abstract: A process for stabilizing enantiomer-enriched cyanohydrins where citric acid and/or boric acid or boric anhydride is added as a stabilizer to the cyanohydrin to be stabilized.

Abstract: Process for enhancement of enantioselectivity in the enzymatic separation of (R)- and (S)-enantiomers of an asymmetric alkynol, a lipase and in the presence of at least one vinyl ester, in which the acid component has at least 4 C atoms, an organic solvent and with the addition of water. Also disclosed is a process for enhancement of enantioselectivity in the enzymatic separation of (R)- and (S)-enantiomers of an alcohol with the aid of the abovementioned vinyl ester under addition of a second vinyl ester having at least 2 C atoms less in the alkyl chain than the vinyl ester used as esterifying agent.

Abstract: Resolution of asymmetric alcohols by reacting them with a vinyl, propenyl or isopropenyl ester of an alkone- or alkene-di- or tricarboxylic acid in the presence of a lipase, and the use thereof.