摘要:
Process for the production of imidazole derivatives of the formula: ##STR1## wherein R.sub.1 is an (R)- or (S)-1-phenylalkyl group, an (R)- or (S)-1-alkoxycarbonyl-1-phenylmethyl group or an (R)- or (S)-1-aryloxycarbonyl-1-phenylmethyl group, R.sub.2 is hydrogen, a substituted or unsubstituted alkanoyl group, an unsubstituted or a substituted benzoyl group, a substituted or an unsubstituted benzyl group, an alkoxycarbonyl group, and aryloxycarbonyl group, an alkoxyalkyl group, a pyranyl group, a substituted or unsubstituted benzenesulfonyl group, an alkylsulfonyl group, a diarylphosphinyl group, a dialkoxyphosphinyl group or a trialkylsilyl group, and A is a sulfur or oxygen atom. A tetronic acid of the formula: ##STR2## wherein A has the above-mentioned meaning, is reacted with a diazonium salt, converting the resultant arylazotetronic acid or the tautomeric arylhydrazone in a further step with a chiral amine into an arylazoamino compound, reducing the arylazoamino compound, converting the resultant diamine, with phosgene or a phosgene-equivalent reagent, into the corresponding imidazole and optionally introducing a protective group by reaction with a substituted or unsubstituted aliphatic or aromatic acid chloride, an aliphatic or aromatic carboxylic acid anhydride, a haloformic acid alkyl ester, a 1-alkoxyalkyl halide, an enol ether, an aromatic or aliphatic sulfonic acid halide, a diarylphosphinic acid halide, a phosphoric acid dialkyl ester halide, a trialkyl silyl halide or a trialkyl silyl acetamide. These imidazole derivatives are suitable as intermediate products for the production of (+) biotin.
摘要:
Process for the production of optically-active di-[3-chloro-2-oxy-propyltrimethylammonium]-tartrate. Racemic 3-chloro-2-oxy-propyltrimethylammonium-chloride is converted by racemate resolution with CaCl.sub.2, for example, into the optically-active di-[3-chloro-2-oxy-propyltrimethylammonium]-tartrate. Such optically-active tartrate compound is dissociated into calcium tartrate and optically-active 3-chloro-2-oxy-propyltrimethylammonium-chloride, and the latter is converted with inorganic cyanides. From the product, the production of optically-active carnitine nitrile chloride can be achieved.
摘要:
Process for the production of tetronic acid from 4-haloacetoacetic ester. The 4-haloacetoacetic ester is transformed into the corresponding 4-tertiary-butoxyacetoacetic ester and the latter is converted by cyclizing ether cleavage into tetronic acid. Preferably the cyclizing ether cleavage is carried out thermolytically at a temperature above 100.degree. C. or is carried out by treatment with an acid at a temperature of 0.degree. to 30.degree. C. Tertiary-butoxyacetoacetic acid ethyl ester is a new compound.
摘要:
Process for the production of optically-active di-[3-chloro-2-oxy-propyltrimethylammonium]-tartrate. Racemic 3-chloro-2-oxy-propyltrimethylammonium-chloride is converted by racemate resolution with optically-active tartaric acid into the optically-active di-[3-chloro-2-oxy-propyltrimethylammonium]-tartrate. Such optically-active tartrate compound is dissociated in tartaric acid to optically-active 3-chloro-2-oxy-propyltrimethylammonium-chloride and the latter is converted with inorganic cyanides. From the product, the production of optically-active carnitine nitrile chloride can be achieved.
摘要:
Process for the production of optically-active di-[3-chloro-2-oxy-propyltrimethylammonium]-tartrate. Racemic 3-chloro-2-oxy-propyltrimethylammonium-chloride is converted by racemate resolution with optically-active tartaric acid into the optically-active di-[3-chloro-2-oxy-propyltrimethylammonium]-tartrate. Such optically-active tartrate compound is dissociated in tartaric acid and optically-active 3-chloro-2-oxy-propyltrimethylammonium-chloride and the latter is converted with inorganic cyanides. From the product, the production of optically-active carnitine nitrile chloride can be achieved.
摘要:
Process for the production of optically-active di-[3-chloro-2-hydroxy-propyltrimethylammonium]-tartrate. Racemic 3-chloro-2-hydroxy-propyltrimethylammonium-chloride is converted by racemate resolution with optically-active tartaric acid into the optically-active di-[3-chloro-2-hydroxy-propyltrimethylammonium]-tartrate. Such optically-active tartrate compound is dissociated in tartaric acid and optically-active 3-chloro-2-hydroxy-propyltrimethylammonium-chloride and the latter is converted with inorganic cyanides. From the product, the production of optically-active carnitine nitrile chloride can be achieved.
摘要:
Process for the production of 2-(2-aminothiazole-4-yl)-2-(syn)-methoxyimino acetic ester. First 4-chloroacetoacetic ester is oximized and then the resultant chlorohydroxyimino ester, in solution form, reacted with thiourea to produce 2-(2-aminothiazole-4-yl)-2-(syn)-hydroxyimino acetic ester. The latter is methylated with dimethyl sulfate using phase transfer catalysis.
摘要:
The process for the production of carnitine hydrochloride which involves reacting an ester of .gamma.-halo-acetoacetic acid having the formula: ##STR1## R.sub.1 is a hydrogen, R.sub.2 is a lower alkyl group having 1 to 10 carbon atoms and X is halogen selected from the group consisting of chlorine or bromine, with an alkali alcoholate, which is present in a stoichiometrically excessive amount, at a temperature between 0.degree. and -40.degree. C. The reaction product is reacted with trimethylamine at a temperature between 10.degree. and 50.degree. C., a (3-carbalkoxy-2-oxopropyl)-trimethyl ammonium halide resulting. The (3-carbalkoxy-2-oxopropyl)-trimethyl ammonium halide is hydrogenated, a carnitine ester resulting. Then the carnitine ester is converted by means of aqueous hydrochloride acid into carnitine hydrochloride.
摘要:
Process for the production of thiotetronic acid wherein 4-chloroacetoacetic acid chloride is reacted with hydrogen sulfide in the presence of an amine.
摘要:
4-Alkoxy-3-pyrrolin-2-on-1-yl acetic acid alkyl esters are intermediate products for the production of cerebrally-active pharmaceutical products. The advantageous process for production of the new intermediate products is described.