- Preparation method of rabeprazole chloride and intermediate thereof
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According to an existing method, acetic anhydride is adopted for a reaction when a formula III is synthesized from a formula IV, the reaction temperature is high, the reaction time is long, a large number of isomer byproducts can be generated in the reaction process, and the product purity is low. When the compound shown in the formula I is synthesized from free alkali of a compound shown in a formula II, halogenated alkane is used as a solvent and thionyl chloride is used as a chlorination reagent for reaction, alkali quenching, water washing extraction and salt formation after concentrationare needed for aftertreatment, the operation is complex, and the production period is long. According to the invention, p-toluenesulfonic acid is added for catalysis when the compound shown as the formula III is prepared, so that the reaction can be carried out at a relatively low temperature, the side reaction is greatly reduced, and the purity of the product is improved. When the compound shownin the formula I is prepared, ethyl acetate is used as a solvent, a product is gradually separated out along with the reaction, the product can be obtained through direct filtration after the reactionis completed, aftertreatment is simple, the product purity is high, and the method is suitable for industrial production.
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Paragraph 0017-0019
(2020/10/05)
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- Metal- and base-free regioselective thiolation of the methyl C(sp3)-H bond in 2-picoline: N -oxides
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A one-pot, two-step synthesis of pyridine-2-ylmethyl thioethers is developed through a TFAA-mediated [3,3]-sigmatropic rearrangement of pyridine N-oxides and TBAB-catalyzed direct conversion of trifluoroacetates into thioethers under metal- and base-free conditions. This methodology enables thiolation of the unactivated methyl C(sp3)-H bond in 2-picolines with thiols. Remarkable features of the method include high regioselectivity, step- and atom-economy, mild conditions, simple operation, wide substrate scope and scalability. Furthermore, the method has been successfully applied to the synthesis of omeprazole sulfide and rabeprazole sulfide without the need for TBAB catalysis. A comprehensive green chemistry metrics analysis indicated that this method is much more efficient and greener than the reported synthesis of rabeprazole sulfide.
- Wang, Dong,Liu, Zhenlin,Wang, Zhentao,Ma, Xinyue,Yu, Peng
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supporting information
p. 157 - 163
(2019/01/11)
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- PROCESS FOR PREPARATION OF PYRIDINYLMETHYLSULPHINYL BENZIMIDAZOLE COMPOUNDS AND PYRIDINE INTERMEDIATES
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Process for preparing 4-chloro-substituted pyridine intermediates of Formula (I), useful for preparation of pyridinylmethylsulphinyl benzimidazole compounds, especially Rabeprazole is disclosed herein. The invention, further describes process for preparation of stable Rabeprazole sodium of high purity in a reproducible and consistent manner.
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Page/Page column 12-13
(2009/10/22)
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- NEW PRAZOLE COMPOUND AND THE USE THEREOF
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The present invention relates to derivatives of compounds (formula (I) or (II)) and their salts, wherein R1 represents lower alkyl or the lower alkyl substituted by halogen atoms, R2 represents straight-chain or branched-chain alkyl containing 1-4 carbon atoms and R3 represents hydrogen atom or alkali metals such as lithium, sodium, potassium or alkaline-earth metals such as magnesium and calcium. In the present invention, compounds with formula (I) or (II) and their derivatives or salts thereof acceptable in pharmacy and pharmacology can remarkably improve the effectiveness of anti-ulcer in alimentary tract, weakly inhibit gastric acid secretion, reduce the risk of stomach cancer and have excellent bio-availability and other in-vive pharmacokinetic characteristics.
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Page/Page column 5
(2008/06/13)
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