1403474-70-3Relevant articles and documents
Azilsartan synthesis process
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, (2019/11/13)
The invention provides an azilsartan synthesis process which is characterized by comprising the following steps: dissolving hydroxylamine hydrochloride into dimethyl sulfoxide, adding sodium bicarbonate at 20-25 DEG C, increasing the temperature to 45-55 DEG C, performing stirring for 45-60 minutes, further adding AQST-SM, increasing the temperature to 80-85 DEG C, and performing a temperature-keeping reaction for 20-22 hours so as to obtain AQST-1; dissolving the AQST-1 into tetrahydrofuran, dropping DBU (diazabicyclo) at 20-25 DEG C, further adding carbonyl diazole, and performing a reactionfor 1.5-2.5 hours at 20-25 DEG C so as to obtain AQST-3; mixing the AQST-3 with a sodium hydroxide solution, increasing the temperature to 70-75 DEG C, and performing a temperature-keeping reaction for 1-2 hours so as to obtain a crude product of AQST; and adding methanol into the crude product of AQST, increasing the temperature to 60-65 DEG C, performing pulping for 45-50 minutes, reducing thetemperature to the room temperature, performing filtering, bleaching filter cakes by using methanol, performing suction filtration till dryness, and performing vacuum drying, so as to obtain an AQST product. By adopting the azilsartan synthesis process provided by the invention, the AQST product is prepared, the yield is high, the content of AQST is high, the content of impurities is low, the quality of the AQST product is remarkably improved, and the azilsartan synthesis process is well applied to production of high-quality azilsartan tablets.
Novel preparation method of azilsartan
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, (2018/11/22)
The invention relates to a novel preparation method of azilsartan with relatively high yield and relatively high purity. A multi-refining or column chromatography method is not needed, in addition, the final yield reduction can not be caused. According to the preparation route provided by the application, the contents of an impurity A and an impurity B can be effectively reduced, the refining frequency is reduced, and the yield is also increased.
Aitch sand smooth intermediate and its and Aitch of preparation method
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Paragraph 0149; 0150; 0151, (2017/01/26)
The invention discloses a preparation method of an intermediate 5B and azilsartan 1. The preparation method of the azilsartan 1 comprises the following steps: 1) in a solvent, mixing a compound 2B with hydroxylamine to react to obtain a compound 3B; 2) in a solvent, mixing the compound 3B prepared in the step 1) with chloroformate to react under the action of alkali to obtain a compound 4B; 3) in a solvent, carrying out cyclization reaction on the compound 4B prepared in the step 2) to obtain a compound 5B; and 4) in a solvent, carrying out esterolysis reaction on the compound 5B prepared in the step 3) under the action of alkali to obtain the azilsartan 1, wherein R is a C6-C10 aryl group or C1-C4 straight-chain or branched-chain alkyl group. The preparation method of the azilsartan intermediate 5B is described as the step 3). The preparation method has the advantages of fewer impurities, short reaction time, higher technical yield and higher product purity, and is suitable for industrial production.