Abstract: An optically active amino acid derivative is produced by N-protecting an optically active 3-haloalanine derivative followed by cyclization, or cyclizing this derivative followed by N-protection to thereby give an optically active N-protected-aziridine-2-carboxylic acid derivative which is protected by a benzenesulfonyl group substituted by nitro at the 2- and/or 4-positions and then treating this product with an organic metal reagent, or by N-protecting an optically active 3-haloalanine derivative to thereby give N-protected-aziridine-2-carboxylic acid which is protected by a benzenesulfonyl group substituted by nitro at the 2- and/or 4-positions and then treating this product with an organic metal reagent. According to this process, natural and unnatural optically active amino acids can be produced from inexpensive materials by using simple procedures.

Abstract: The present invention provides a method capable of suppressing a decrease in optical purity due to the exposure to heat during distillation of an optically active epoxide to permit an optically active epoxide of high quality to be simply obtained on an industrial scale. In the method, an optically active epoxide is distilled in the presence of a base to suppress a decrease in optical purity.

Abstract: An optically active amino acid derivative is produced by N-protecting an optically active 3-haloalanine derivative followed by cyclization, or cyclizing this derivative followed by N-protection to thereby give an optically active N-protected-aziridine-2-carboxylic acid derivative which is protected by a benzenesulfonyl group substituted by nitro at the 2- and/or 4-positions and then treating this product with an organic metal reagent, or by N-protecting an optically active 3-haloalanine derivative to thereby give N-protected-aziridine-2-carboxylic acid which is protected by a benzenesulfonyl group substituted by nitro at the 2- and/or 4-positions and then treating this product with an organic metal reagent. According to this process, natural and unnatural optically active amino acids can be produced from inexpensive materials by using simple procedures.

Abstract: There is provided a process for preparing a pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid which comprises condensing an amino acid and N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine.N-carboxyanhydride under basic condition, carrying out decarboxylation under between neutral and acidic condition to obtain N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid, and forming a pharmacologically acceptable salt thereof, wherein the production of a by-product (3): is suppressed by carrying out in an aqueous liquid a series of operations till formation of the pharmacologically acceptable salt or till isolation of the pharmacologically acceptable salt. The present invention enables to prepare the pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid having high quality, in a commercial scale with high yield and economical efficiency.

Abstract: There is provided a process for preparing a pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid which comprises condensing an amino acid and N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine.

Abstract: An optically active amino acid derivative is produced by N-protecting an optically active 3-haloalanine derivative followed by cyclization, or cyclizing this derivative followed by N-protection to thereby give an optically active N-protected-aziridine-2-carboxylic acid derivative which is protected by a benzenesulfonyl group substituted by nitro at the 2- and/or 4-positions and then treating this product with an organic metal reagent, or by N-protecting an optically active 3-haloalanine derivative to thereby give N-protected-aziridine-2-carboxylic acid which is protected by a benzenesulfonyl group substituted by nitro at the 2- and/or 4-positions and then treating this product with an organic metal reagent.

Abstract: There is provided a process for preparing a pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid which comprises condensing an amino acid and N-(1(S) -ethoxycarbonyl-3-phenylpropyl)-L-alanine N-carboxy-anhydride under basic condition, carrying out decarboxylation under between neutral and acidic condition to obtain N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid, and forming a pharmacologically acceptable salt thereof, wherein the production of a by-product (3): is suppressed by carrying out in an aqueous liquid a series of operations till formation of the pharmacologically acceptable salt or till isolation of the pharmacologically acceptable salt. The present invention enables to prepare the pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid having high quality, in a commercial scale with high yield and economical efficiency.

Abstract: There is provided a process for preparing a pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid which comprises condensing an amino acid and N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine.

Abstract: An industrial advantage process for producing high-purity 3-hydroxytetrahydrofuran easily and simply, which comprises reducing a 4-halo-3-hydroxybutyric acid ester (1) with a boron hydride compound and/or an aluminum hydride compound as a reducing agent in an organic solvent immiscible with water; treating the reaction mixture with an acid and water to thereby effect conversion to the corresponding 4-halo-1,3-butanediol and at the same time giving an aqueous solution containing said compound; carrying out the cyclization reaction of the 4-halo-1,3-butanediol in said aqueous solution; extracting the resulting 3-hydroxytetrahydrofuran from the 3-hydroxytetrahydrofuran-containing aqueous solution using an organic solvent immiscible with water; and isolating the 3-hydroxytetrahydrofuran by concentration and/or distillation of the solution obtained.

Abstract: There is provided a process for preparing a pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid which comprises condensing an amino acid and N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine.N-carboxyanhydride under basic condition, carrying out decarboxylation under between neutral and acidic condition to obtain N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid, and forming a pharmacologically acceptable salt thereof, wherein the production of a by-product (3): is suppressed by carrying out in an aqueous liquid a series of operations till formation of the pharmacologically acceptable salt or till isolation of the pharmacologically acceptable salt. The present invention enables to prepare the pharmacologically acceptable salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-amino acid having high quality, in a commercial scale with high yield and economical efficiency.

Abstract: The process for producing N2-(1(S)-carboxy-3-phenylpropyl)-L-lysyl-L-proline in a simple, efficient and industrially advantageous manner, including the following steps: 1) subjecting N2-(1(S)-alkoxycarbonyl-3-phenylpropyl)-N6-trifluoroacetyl-L-lysyl-L-proline (1) to alkali hydrolysis in a mixed solution composed of water and a hydrophilic organic solvent using an inorganic base in an amount of n molar equivalents (n ≧ 3) per mole of the above compound (1), 2) neutralizing the hydrolysis product using an inorganic acid in an amount of (n − 1) to n molar equivalents (n ≧ 3) to form a compound (2) and removing the inorganic salt formed by causing the same to precipitate out from a solvent system suited for decreasing the solubility of the inorganic salt, and 3) causing the compound (2) existing in the mixture after removal of the inorganic salt to crystallize out at the isoelectric point thereof and thereby recovering the compound (2) in the form of crystals while retaining the salts including the

Abstract: A process for simply and easily crystallizing a maleate salt of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-L-proline (enalapril) having a high quality out of an aqueous liquid, which comprises mixing an aqueous liquid having a pH of not less than 4 and containing N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanyl-L-proline, maleic acid and a base with an amount of an acid sufficient to convert substantially all the base into a neutral salt.

Abstract: The present invention provides a process for reducing carbonyl compounds to hydroxy compounds, in particular stereoselectively reducing .alpha.-aminohaloketone derivatives, under mild conditions in an easy and simple manner, which comprises reacting a carbonyl compound of the general formula (1) with an organoaluminum compound of the general formula (4) to provide the corresponding alcohol compound of the general formula (5).

Abstract: An object of the present invention is to provide a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative via efficient and industrially utilizable steps.The present invention provides a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative represented by the general formula (2) given below which comprises hydrolyzing an .alpha.-amino-.alpha.', .alpha.-dihaloketone derivative of the general formula (1) given below in the presence of a base, followed by protecting the amino group or without protecting the same.

Abstract: An object of the present invention is to provide a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative via efficient and industrially utilizable steps.The present invention provides a process for producing a .beta.-amino-.alpha.-hydroxy acid derivative represented by the general formula (2) given below which comprises hydrolyzing an .alpha.-amino-.alpha.', .alpha.'-dihaloketone derivative of the general formula (1) given below in the presence of a base, followed by protecting the amino group or without protecting the same.