专利号:US-2008032964-A1 优先权日:2006-04-10 标题:Process for the synthesis of azetidinone 发明人:KANSAL VINOD K; AHMAD SUHAIL; MARIAPPAN SHANMUGAVEL; TYAGI BHUPENDRA; PERLMAN NURIT; LE PAIH JACQUES; ZANOTTI-GEROSA ANTONIO 权利人:KANSAL VINOD K; AHMAD SUHAIL; MARIAPPAN SHANMUGAVEL; TYAGI BHUPENDRA; PERLMAN NURIT; LE PAIH JACQUES; ZANOTTI-GEROSA ANTONIO 摘要:Provided are intermediates useful for the synthesis of hydroxyl-alkyl substituted azetidinones, processes of their preparation, and processes for the synthesis of certain hydroxyl-alkyl substituted azetidinones. Also provided are processes for the synthesis of 1-(4-fluorophenyl)-3(R)-[3-(4-fluorophenyl)-3(S)-hydroxypropyl]-4(S)-(4-hydroxyphenyl)-2-azetidinone, or ezetimibe.
专利号:US-8383810-B2 优先权日:2004-12-20 标题:Process for the synthesis of azetidinones 发明人:THIRUVENGADAM TIRUVETTIPURAM K; CHIU JOHN S; FU XIAOYONG; MCALLISTER TIMOTHY L 权利人:MERCK SHARP & DOHME; THIRUVENGADAM TIRUVETTIPURAM K; CHIU JOHN S; FU XIAOYONG; MCALLISTER TIMOTHY L 摘要:A process is provided for preparing azetidinones useful as intermediates in the synthesis of penems and as hypocholesterolemic agents, comprising reacting a β-(substituted-amino)amide, a β-(substituted-amino)acid ester, or a β-(substituted-amino)thiolcarbonic acid ester with a silylating agent and a cyclizing agent selected from the group consisting of alkali metal carboxylates, quaternary ammonium carboxylates, quaternary ammonium hydroxides, quaternary ammonium alkoxides, quaternary ammonium aryloxides and hydrates thereof, or the reaction product of: (i) at least one quaternary ammonium halide and at least one alkali metal carboxylate; or (ii) at least one quaternary ammonium chloride, quaternary ammonium bromide, or quaternary ammonium iodide and at least one alkali metal fluoride, wherein a quaternary ammonium moiety of the cyclizing agent is unsubstituted or substituted by one to four groups independently selected from the group consisting of alkyl, arylalkyl and arylalkyl-alkyl.
专利号:US-5728827-A 优先权日:1993-07-09 标题 :Process for the synthesis of azetidinones 发明人:THIRUVENGADAM TIRUVETTIPURAM K; MCALLISTER TIMOTHY; TANN CHOU-HONG 权利人:SCHERING CORP 摘要:This invention provides a process for preparing azetidinones useful as intermediates in the synthesis of penems and as hypocholesterolemic agents, particularly for azetidinones substituted in the C-3 and C-4 positions and optionally substituted at the ring nitrogen, comprising reacting a β-(substituted-amino)amide, a β-(substituted-amino)acid ester, or a β-(substituted-amino)thiolcarbonic acid ester with a silylating agent and a cyclizing agent.
专利号:US-11713329-B2 优先权日:2018-12-10 标 题 :Intermediates useful in the preparation of halichondrin compounds and methods for preparing the same 发明人:XU WEIPING 权利人:BEIJING TIENYI LUFU PHARMATECH CO LTD 摘要:The invention relates to intermediates useful in the preparation of halichondrin compounds, methods for preparing the same and use thereof, such as halichondrins, eribulin, or their analogs. The intermediates, the methods and use thereof are used for the synthesis of the C20-C26 fragment of halichondrin compounds. The raw materials in the synthetic route of the invention are cheap and easily obtained, the sources and the qualities of the raw materials are reliable. The choice of the methods useful in the synthesis of chiral central structures are based on the structural characteristics of the reactants, thus effectively improving the synthesis efficiency, reducing the difficulties and risks of product quality control, and avoiding the use of highly toxic and expensive organotin catalysts to significantly decrease costs and improve environmental friendliness.
专利号:US-6093812-A 优先权日:1991-07-23 标 题 :Process for the stereospecific synthesis of azetidinones 发明人:THIRUVENGADAM TIRUVETTIPURAM K; TANN CHOU-HONG; LEE JUNNING; MCALLISTER TIMOTHY; COLON CESAR; BARTON DEREK H R; BRESLOW RONALD; SUDHAKAR ANANTHA 权利人:SCHERING CORP 摘要:This invention provides an improved process for producing azetidinones. More particularly, this invention provides the steps of producing an trans-azetidinone represented by the formula from a carboxylic acid R2-D-CH2COOH, an aldehyde R1-A-CHO and an amine RNH2, by the steps of: (a1) converting a carboxylic acid to the corresponding acid chloride; (b1) deprotonating a chiral oxazolidinone and treating the resulting anion with the product of step (a1); (c1) enolizing the product of step (b1) and condensing with the aldehyde; (d1) hydrolyzing the product of step (c1); (e1) condensing the product of step (d1) with the amine; and (f1) cyclizing the product of step (e1). Alternatively, the process comprises (a2) enolizing the product of step (b1) and condensing, in the presence of a Lewis acid, with a Schiff's base prepared from the aldehyde and the amine; and (b2) cyclizing the product of step (a2).
专利号:US-6207822-B1 优先权日:1998-12-07 标 题:Process for the synthesis of azetidinones 发明人:THIRUVENGADAM TIRUVETTIPURAM K; FU XIAOYONG; TANN CHOU-HONG; MCALLISTER TIMOTHY L; CHIU JOHN S; COLON CESAR 权利人:SCHERING CORP 摘要:This invention provides a process for preparing the hypocholesterolemic compoundcomprising:(a) reacting p-fluorobenzoylbutyric acid with pivaloyl chloride and acylating the product with a chiral auxiliary to obtain a ketone of formula IV:(b) reducing the ketone of formula IV in the presence of a chiral catalyst to an alcohol:(c) reacting the chiral alcohol of step (b), an imine and a silyl protecting agent, then condensing the protected compounds to obtain a beta-(substituted-amino)amide of formula VII:(d) cyclizing the beta-(substituted-amino)amide of formula VII with a silylating agent and a fluoride ion catalyst to obtain a protected lactam of the formula VIII:and removing the protecting groups.The intermediates of formulas VII and VIII are also claimed.
摘要:Klapars, A., Science of Synthesis: Cross Coupling and Heck-Type Reactions, (2012) 2, 246. 摘要:Elliott, M. C.; Jones, D. H., Science of Synthesis: Multicomponent Reactions, (2013) 2, 263. 摘要:Li, H.; Wang, Y.; Liu, Q., Science of Synthesis: Base-Metal Catalysis, (2023) 2, 585. 参考文献:10.1007/bf01388170 摘要:Calmes M, Daunis J. How to build optically active alpha-amino acids. Amino Acids. 1999;16(3-4):215–50. doi: 10.1007/bf01388170.