摘要:
An industrially advantageous process for preparing high-purity 3-hydroxytetrahydrofuran easily and simply, which comprises converting a 4-halo-3-hydroxybutyric acid ester into a 4-halo-1,3-butanediol by reducing the ester with a boron hydride compound and/or an aluminum hydride compound in an organic solvent incompatible with water and treating the obtained reaction mixture with an acid and water, recovering an aqueous solution containing the diol, conducting the cyclization of the diol in this aqueous solution, extracting the resulting solution with an organic solvent incompatible with water, and isolating 3-hydroxytetrahydrofuran from the extract through concentration and/or distillation.
摘要:
The objective of the present invention is to provide an optically active imidazolidinone derivative widely usable for synthesizing an optically active amino acid, a method of easily producing the derivative, and a method of easily producing an optically active amino acid by using the derivative. The objective can be achieved by producing an optically active amino acid using a novel optically active imidazolidinone derivative represented by a general formula (3) and the like. According to the method of the present invention, an optically active imidazolidinone derivative can be obtained by preferential crystallization from a mixture of isomers of the imidazolidinone derivative. Therefore, an optically active amino acid can be easily and stereoselectively produced without cumbersome procedures required for the conventional methods, such as resolution of diastereomers, synthesis from an optically active amino acid and resolution of isomers by silica gel column cromatography.
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:
The problem to be solved of the present application is to provide a method for producing a novel pyrimidine derivative from an inexpensive compound which is industry-available with ease, and a method for producing an important intermediate of an HMG-CoA reductase inhibitor. The problem can be solved by, for example, reacting the compound (1) with the compound represented by (OR 1 ) 3P to obtain the phosphonate ester (3) and reacting the phosphonate ester (3) with the compound (4) in the presence of a base to obtain an HMG-CoA reductase inhibitor intermediate (5).
摘要:
A process for preparing optically active azetidine -2-carboxylic acid efficiently, easily, simply, and industrially advantageously by cyclizing an optically active 4-amino- 2-halogenobutyric acid in an optical yield of as high as 90 % or above. Specifically, a process for preparing optically active azetidine-2-carboxylic acid of formula (2) (wherein * represents an asymmetric carbon atom) by cyclizing an optically active 4-amino-2-halogenobutyric acid of the general formula (1) (wherein X is halogeno and * represents an asymmetric carbon atom) in the presence of an alkaline earth metal oxide, an alkaline earth metal hydroxide except barium hydroxide, or an organic amine.
摘要:
The invention provides a process for producing optically active azetidine-2-carboxylic acid with good efficiency, expedience, and commercial advantage, which comprises cyclizing an optically active 4-amino-2-halogenobutyric acid in an optical yield of as high as 90% or more. It is a process for producing optically active azetidine-2-carboxylic acid of the general formula (2), in which ∗ denotes an asymmetric carbon atom, which comprises cyclizing an optically active 4-amino-2-halogenobutyric acid of the general formula (1),in which X represents a halogen atom and ∗ denotes an asymmetric carbon atom, in the presence of an oxide of an alkaline earth metal, a hydroxide of an alkaline earth metal excepting barium, or an organic amine.
摘要:
An industrially advantageous process for preparing high-purity 3-hydroxytetrahydrofuran easily and simply, which comprises converting a 4-halo-3-hydroxybutyric acid ester into a 4-halo-1,3-butanediol by reducing the ester with a boron hydride compound and/or an aluminum hydride compound in an organic solvent incompatible with water and treating the obtained reaction mixture with an acid and water, recovering an aqueous solution containing the diol, conducting the cyclization of the diol in this aqueous solution, extracting the resulting solution with an organic solvent incompatible with water, and isolating 3-hydroxytetrahydrofuran from the extract through concentration and/or distillation.