摘要:
A process for preparing an optically active (2S,3S)-allophenylnorstatin derivative (I) is disclosed, comprising asymmetrically hydrogenating a 4-phenyl-2-halogeno-3-oxobutyric ester (III) in the presence of a ruthenium-phosphine complex to obtain a 4-phenyl-(2S)-halogeno-(3R)-hydroxybutyric ester (IV), epoxidizing the ester (IV) in the presence of a base to obtain a 4-phenyl-(2S,3R)-epoxybutyric ester (V), reacting the ester (V) with a tri(lower alkyl)silylazide or a (lower alkyl)diarylsilylazide in the presence of a Lewis to obtain a (3S)-azido-4-phenyl-(2S)-trisubstituted silyloxybutyric ester (VI), hydrogenolyzing the ester (VI) into a (2S,3S)-allophenylnorstatin derivative (VII), protecting the amino group of the compound (VII), and, if desired, hydrolyzing the compound before or after the amino group protection. Compounds (I) can be obtained at high optical purity safely and in good yield.
摘要:
Disclosed is a 2-phenyl-2-(2'-piperidinylidene)acetate derivative suitably used for a raw material of a 2-phenyl-2-(2'-piperidinyl)acetate derivative and a process for manufacturing the same. Also disclosed is a process for manufacturing an optically active 2-phenyl-2-(2'-piperidinyl)acetate derivative which is a major intermediate for an antidepressant. The 2-phenyl-2-(2'-piperidinylidene)acetate derivative is manufactured by cyclizing a 7-(N-substituted amino)-3-oxo-2-heptanoate derivative. The optically active 2-phenyl-2-(2'-piperidinyl)acetate derivative is manufactured by asymmetrically hydrogenating the 2-phenyl-2-(2'-piperidinylidene)acetate derivative in the presence of a complex of a Group VIII transition metal or an acid.
摘要:
Compounds represented by the following general structural formula (1) and methods for producing the compounds: ##STR1## R.sup.1 represents a group such as benzyloxycarbonyl, R.sup.2 represents a lower alkyl group, R.sup.3 represents a hydrogen atom or a protecting group, each of M.sup.1 and M.sup.2 represents a metal atom, and n represents the atomic valence of M.sup.1. Intermediates for HMG-CoA reductase inhibitors can be prepared safely and easily from these compounds.
摘要:
Disclosed is a 7-(N-substituted amino)-3-oxo-2-phenylheptanoate derivative, 7-(N-substituted amino)-3-hydroxy-2-phenylheptanoate derivative, and 7-(N-substituted amino)-3-benzenesulfonyloxy-2-phenylheptanoate derivative, which are quite important major intermediates for an antidepressant. The 7-(N-substituted amino)-3-oxo-2-phenylheptanoate derivative can be manufactured by condensing an enolate of phenylacetates with a 5-(N-substituted amino) pentanoate derivative.
摘要:
A novel process for producing 3-oxocarboxylic acid esters, which are useful as intermediates in the synthesis of ceramides to be used as a humectant, biodegradable polymers, drugs, etc., at a high purity and a high yield without requiring any troublesome procedure, is disclosed. The process comprises reacting an acetoacetic ester with a calcium compound, a barium compound or a strontium compound in the presence of an organic solvent at a temperature of 10 to 120.degree. C., further reacting the obtained product with a carboxylic acid chloride to thereby acylate it, and then adding thereto an alcohol in an amount 1 to 5 times by mol as much as the calcium compound, barium compound or strontium compound to thereby deacetylate the same.
摘要:
A production process for obtaining optically active (3R,1'S)-1-benzyl-3-�(1'-N-methylamino)ethyl!pyrrolidine or (3R,1'S)-3-�(1'-N-methylamino)ethyl!pyrrolidine used as an intermediate for the synthesis of pharmaceutical preparations such as anti-fungal agents in high purity and in high yield using a reduced number of processing steps. The process comprises asymmetrically hydrogenating 3-acetyl-1-benzyl-2-pyrrolidinone in the presence of a complex formed from bidentate phosphine and ruthenium as a catalyst to provide (3S,1'R)-1-benzyl-3-�(1'-hydroxy)ethyl!-2-pyrrolidinone, then reducing with a hydride to provide (3R,1'R)-1-benzyl-3-�(1'-hydroxy)ethyl!pyrrolidine, mesylating or tosylating to provide (3R,1'R)-1-benzyl-3-�(1'-methanesulfonyloxy)ethyl!pyrrolidine or (3R,1'R)-1-benzyl-3-�(1'-p-toluenesulfonyloxy)ethyl!pyrrolidine, and reacting with methylamine to obtain (3R,1'S)-1-benzyl-3-�(1'-N-methylamino)ethyl!pyrrolidine. The prcess may further comprise de-benzylating (3R,1'S)-1-benzyl-3-�(1'-N-methylamino)ethyl!pyrrolidine to obtain (3R,1'S)-3-�(1'-N-methylamino)ethyl!pyrrolidine.
摘要:
The present invention relates to a flavor composition or fragrance composition which can satisfy diversified requirements for flavored products, as well as to a flavor-improving agent which can improve the quality and release of aroma of a beverage or food. More particularly, the present invention relates to a flavor composition or fragrance composition which comprises an optically active S-alkyl 2-methylbutanethioate as an active ingredient, a flavor- or fragrance-added product, a flavor-improving agent which comprises an optically active S-alkyl 2-methylbutanethioate as an active ingredient, and a beverage or food having an improved flavor. The optically active S-alkyl 2-methylbutanethioate includes S-alkyl(R)-2-methylbutanethioate and S-alkyl(S)-2-methylbutanethioate.
摘要:
(2R,3R)-3-N-(L-aspartyl)amino-1-(1-methyl-2-norbornyl)-2-butanol and (2R,3R)-3-N-(L-aspartyl)amino-1-(3-methyl-2-norbornyl)-2-butanol as well as a sweetener comprising the same are disclosed. These compounds, which have excellent sweetness characteristics and are stable in acidic aqueous solutions, are highly useful as a sweetener in various fields.
摘要:
(A) a diacylated dopamine derivative represented by the formula (I): ##STR1## wherein R.sup.1 represents an alkyl group having 3 to 7 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, substituted or unsubstituted phenyl group or a substituted or unsubstituted nitrogen-containing heterocyclic group; and R.sup.2 represents a hydrogen atom or a lower alkyl group; or a salt thereof; and(B) one or more compounds selected from lactic acid esters, fatty acid monoglycerides and higher alcohols; optionally together with(C) an unsaturated fatty acid monohydric alcohol ester. This preparation has a sustained effect, a high skin permeability and a low skin irritativeness.
摘要:
The present invention relates to a flavor composition or fragrance composition which can satisfy diversified requirements for flavored products, as well as to a flavor-improving agent which can improve the quality and release of aroma of a beverage or food. More particularly, the present invention relates to a flavor composition or fragrance composition which comprises an optically active S-alkyl 2-methylbutanethioate as an active ingredient, a flavor- or fragrance-added product, a flavor-improving agent which comprises an optically active S-alkyl 2-methylbutanethioate as an active ingredient, and a beverage or food having an improved flavor. The optically active S-alkyl 2-methylbutanethioate includes S-alkyl(R)-2-methylbutanethioate and S-alkyl(S)-2-methylbutanethioate.