A method for preparing isophorone diisocyanate by (1) reacting isophorone with hydrogen cyanide in the presence of a catalyst to obtain isophorone nitrile; (2) reacting the isophorone nitrile obtained in step (1) with ammonia gas and hydrogen in the presence of a catalyst to obtain isophorone diamine; and (3) subjecting the isophorone diamine to a phosgenation reaction to obtain the isophorone diisocyanate, wherein the content of impurities containing a secondary amine group in the isophorone diamine that undergoes the phosgenation reaction in step (3) is ≤0.5 wt. The method reduces the content of hydrolyzed chlorine in the isophorone diisocyanate product, improves the yellowing resistance of the product, and the harm due to presence of hydrolyzed chlorine in the product is reduced.

A method for preparing isophorone diisocyanate by (1) reacting isophorone with hydrogen cyanide in the presence of a catalyst to obtain isophorone nitrile; (2) reacting the isophorone nitrile obtained in step (1) with ammonia gas and hydrogen in the presence of a catalyst to obtain isophorone diamine; and (3) subjecting the isophorone diamine to a phosgenation reaction to obtain the isophorone diisocyanate, wherein the content of impurities containing a secondary amine group in the isophorone diamine that undergoes the phosgenation reaction in step (3) is ≤0.5 wt. The method reduces the content of hydrolyzed chlorine in the isophorone diisocyanate product, improves the yellowing resistance of the product, and the harm due to presence of hydrolyzed chlorine in the product is reduced.

Disclosed herein is a class of chiral binuclear metal complexes for stereoselective hydrolysis of saccharides and glycosides, and more particular chiral binuclear transition metal complex catalysts that discriminate epimeric glycosides and α- and β-glycosidic bonds of saccharides in aqueous solutions at near physiological pHs. The chiral binuclear metal complexes include a Schiff-base-type ligand derived from a chiral diamino building block, and a binuclear transition metal core, each which can be varied for selectivity. The metal core is a Lewis-acidic metal ion, such as copper, zinc, lanthanum, iron and nickel. The Schiff-base may be a reduced or non-reduced Schiff-base derived from aliphatic linear, aliphatic cyclic diamino alcohols or aromatic aldehydes. The ligand can be a penta- or heptadentate ligand derived from pyridinecarbaldehydes, benzaldehydes, linear or cyclic diamines or diamino alcohols.

Disclosed herein is a class of chiral binuclear metal complexes for stereoselective hydrolysis of saccharides and glycosides, and more particular chiral binuclear transition metal complex catalysts that discriminate epimeric glycosides and α- and β-glycosidic bonds of saccharides in aqueous solutions at near physiological pHs. The chiral binuclear metal complexes include a Schiff-base-type ligand derived from a chiral diamino building block, and a binuclear transition metal core, each which can be varied for selectivity. The metal core is a Lewis-acidic metal ion, such as copper, zinc, lanthanum, iron and nickel. The Schiff-base may be a reduced or non-reduced Schiff-base derived from aliphatic linear, aliphatic cyclic diamino alcohols or aromatic aldehydes. The ligand can be a penta- or heptadentate ligand derived from pyridinecarbaldehydes, benzaldehydes, linear or cyclic diamines or diamino alcohols.

The present invention relates to the field of medicinal chemistry, and relates to an ethylenediamine compound represented by Formula A, pharmaceutically acceptable salts, stereoisomers, tautomers or isomer mixtures, hydrates thereof, solvates thereof, or prodrugs thereof, and use thereof in the treatment of tuberculosis.

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To provide a polyamide resin composition preventing mold fouling during molding and capable of producing a molded product with an excellent color tone, as well as a molded product, a method for producing a molded product, and an antioxidant. The composition is a resin composition containing: a polyamide resin constituted of diamine-derived constituent units and dicarboxylic acid-derived constituent units, 70 mol % or more of the diamine-derived constituent units being derived from a compound represented by Formula (1), and 70 mol % or more of the dicarboxylic acid-derived constituent units being derived from an α,ω-linear aliphatic dicarboxylic acid having from 8 to 12 carbon atoms; and a compound represented by Formula (1), where R.sup.1 and R.sup.2 each independently represent an alkyl group having from 1 to 4 carbon atoms, and n1 and n2 are each independently an integer from 0 to 4, wherein a content of the compound represented by Formula (1) is from 3 to 100 mass ppm of the resin composition.

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A catalyst composition for hydrogenating 4,4′-methylenedianiline is provided. The catalyst composition includes a carrier including aluminum oxide and magnesium oxide, a rhodium-ruthenium active layer loaded on the surface of the carrier, and organic amine solvent. The weight percentage of magnesium oxide in the carrier is between 12% and 30%. A method for preparing 4,4′-methylene bis(cyclohexylamine) using the catalyst composition is also provided.

A catalyst composition for hydrogenating 4,4′-methylenedianiline is provided. The catalyst composition includes a carrier including aluminum oxide and magnesium oxide, a rhodium-ruthenium active layer loaded on the surface of the carrier, and organic amine solvent. The weight percentage of magnesium oxide in the carrier is between 12% and 30%. A method for preparing 4,4′-methylene bis(cyclohexylamine) using the catalyst composition is also provided.

A catalyst composition for hydrogenating 4,4′-methylenedianiline derivatives is provided. The catalyst composition includes a carrier including aluminum oxide and magnesium oxide, a rhodium-ruthenium active layer loaded on the surface of the carrier, and a solvent including an organic amine. The weight percentage of magnesium oxide in the carrier is between 12% and 30%. A method for preparing 4,4′-methylene bis(cyclohexylamine) derivatives using the catalyst composition is also provided.

A catalyst composition for hydrogenating 4,4′-methylenedianiline derivatives is provided. The catalyst composition includes a carrier including aluminum oxide and magnesium oxide, a rhodium-ruthenium active layer loaded on the surface of the carrier, and a solvent including an organic amine. The weight percentage of magnesium oxide in the carrier is between 12% and 30%. A method for preparing 4,4′-methylene bis(cyclohexylamine) derivatives using the catalyst composition is also provided.