38results about How to "High split yield" patented technology

The invention relates to the technical field of medicine preparation, and discloses a preparation method of rotigotine, which uses 5-methoxy-2-tetralone as an initial raw material, reacts with R-α-methylbenzylamine, and undergoes desorption Benzyl reduction, chiral resolution of S-mandelic acid, and then react with propionyl chloride reagent to generate amide compound, then reduce it with sodium borohydride reagent, and finally react with 2-(thiophen-2-yl) 2-nitrobenzenesulfonic acid ethyl Ester reaction to give rotigotine. The preparation process route is that the rotigotine of the present invention has mild preparation conditions, simple operation, high yield of key intermediates, high optical purity, easy industrial scale-up production, and good application prospects.

The invention relates to a resolution method of DL-panthenolactone. The resolving agent used in the existing resolution method has low selectivity when resolving DL-panthenolactone, which makes the total utilization rate of DL-panthenolactone low and improves the efficiency of resolving DL-panthenolactone. Cost of production. The resolving agent used in the present invention is an organic base R-NH 2 , where R is C 15 h 15 , comprising the following steps: a) reacting the purified resolving agent with acid, adding water, heating and dissolving, adding dropwise DL-pantothenolactone hydrolyzate, resolving agent: the molar ratio of DL-pantothenolactone=0.5- 0.7:1; b) Suction filter the reaction liquid obtained in a, carry out racemization on the filter cake, recover the resolving agent, add an organic solvent to the filtrate for azeotropic dehydration, distill off the excess organic solvent for crystallization. The present invention obviously improves the selectivity of the resolving agent to D-panthenolactone, improves the total utilization rate of DL-panthenolactone, has high resolution yield, reduces the amount of resolving agent and is easy to recycle repeatedly, reducing Breakdown of the production cost of DL-panthenolactone.

The invention relates to a method for preparing L-2-aminopropanol by means of splitting DL-2-aminopropanol. The method includes steps of 1), dissolving L-tartaric acid in water to obtain L-tartaric acid aqueous solution; 2), dissolving the DL-2-aminopropanol in alcohol solvents at the room temperature, then stirring the DL-2-aminopropanol and the alcohol solvents under cooling conditions, simultaneously completely dropwise adding the L-tartaric acid aqueous solution into the DL-2-aminopropanol to obtain mixed solution, then cooling the mixed solution until the temperature of the mixed solution reaches 0-5 DEG C, and preserving heat to obtain cooled solution; 3), adding a small quantity of crystal seeds into the cooled solution, allowing the cooled solution to stand still at the temperatures ranging from -15 DEG C to +25 DEG C, crystallizing the cooled solution at the temperatures ranging from -15 DEG C to +25 DEG C for 16-24 hours and separating out L-tartaric acid-L-2-aminopropanol acid salt crystals; 4), dissolving the L-tartaric acid-L-2-aminopropanol acid salt crystals by the aid of alcohol solvents, adding inorganic bases into the L-tartaric acid-L-2-aminopropanol acid salt crystals in batches, stirring the inorganic bases and the L-tartaric acid-L-2-aminopropanol acid salt crystals until amino alcohol is completely free, carrying out suction filtration and carrying out reduced-pressure distillation on filter liquid to obtain the L-2-aminopropanol. The method has the advantages that processes are easy to implement, raw materials are high in utilization rate, and accordingly the method is suitable for large-scale production.

Provided in the present invention is a method for the enzymatic resolution of an isavuconazole intermediate. Enantiomeric impurities in (2R,3S)-isavuconazole intermediate I are hydrolyzed to (2S,3S)-carboxylic acid by-product by nitrilase, and the products are separated and purified to obtain the optically pure (2S,3R)-isavuconazole intermediate I.