摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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 trifluoroacetic acid-derived organic acid salt in a state dissolved in the mother liquor.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
Disclosed is a method for stabilizing a carbodiimide derivative (1) which is a condensing agent useful for production of general synthetic chemical products. Also disclosed is a stabilized composition of the carbodiimide derivative. The method is characterized in that the carbodiimide derivative (1) is handled in an atmosphere wherein the concentration of molecular oxygen in the gas phase within a container is set at not more than 3% by volume and/or in the co-presence of at least one compound selected from the group consisting of antioxidants, N-oxyl compounds, sulfur compounds, amines and Lewis acids.