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.
摘要:
This invention relates to processes for the production of optically active 2-(disubstituted aryl)cyclopropylamine compounds and optically active 2-(disubstituted aryl)cyclopropane carboxamide compounds which are useful intermediates for the preparation of pharmaceutical agents, and in particular the compound [1S-(1α,2α,3β(1S*,2R*),5β)]-3-[7-[2-(3,4-difluorophenyl)-cyclopropyl]amino]-5-(propylthio)-3H-1,2,3-triazolo[4,5-d]pyrimidin-3-yl)-5-(2-hydroxyethoxy)-cyclopentane-1,2-diol.
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:
The method for producing a surfactin or a salt thereof according to the present invention comprises the steps of adding an organic solvent containing a branched alkyl alcohol to a culture fluid containing the surfactin or the salt thereof, or to a solution obtained by removing an insoluble component from the culture fluid, and extracting the surfactin or the salt thereof with the organic solvent,wherein the surfactin or the salt thereof is represented by the formula (1): wherein * indicates an optically active center; X is an amino acid selected from leucine, isoleucine and valine; R is a C9-13 alkyl group or a C9-13 branched alkyl group; and M is an alkali metal, an alkaline earth metal, an optionally-substituted amine or the like.
摘要:
This invention relates to processes for the production of optically active 2-(disubstituted aryl)cyclopropylamine compounds and optically active 2-(disubstituted aryl) cyclopropane carboxamide compounds which are useful intermediates for the preparation of pharmaceutical agents, and in particular the compound [1S-(1α,2α,3β(1S*,2R*),5β]-3-[7-[2-(3,4-difluorophenyl)-cyclopropyl]amino]-5-(propylthio)-3H-1,2,3-triazolo[4,5-d]pyrimidin-3-yl)-5-(2-hydroxyethoxy)-cyclopentane-1,2-diol.
摘要:
This invention relates to processes for the production of optically active 2-(disubstituted aryl)cyclopropylamine compounds and optically active 2-(disubstituted aryl)cyclopropane carboxamide compounds which are useful intermediates for the preparation of pharmaceutical agents, and in particular the compound [1S-(1α,2α,3β(1S*,2R*),5β)]-3-[7-[2-(3,4-difluorophenyl)-cyclopropyl]amino]-5-(propylthio)-3H-1,2,3-triazolo[4,5-d]pyrimidin-3-yl)-5-(2-hydroxyethoxy)-cyclopentane-1,2-diol.
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:
The present invention relates to a process for producing an N-carbamoyl-tert-leucine, characterized in mixing tert-leucine with an isocyanic acid compound while a pH of the mixture is kept at not less than 8.0 and not more than 13.5, wherein an amount of the isocyanic acid compound is not less than 0.9 times by mole and not more than 1.1 times by mole relative to an amount of the tert-leucine. According to the present invention, it becomes possible to easily produce an N-carbamoyl-tert-leucine with high efficiency, while the generation of by-products such as a dipeptide-like compound and a urea compound is prevented.
摘要:
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.
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.