860994-58-7Relevant articles and documents
Novel synthesis method of oseltamivir
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Paragraph 0093-0098, (2021/05/19)
The invention provides a novel synthesis method of oseltamivir. The synthesis method comprises the following steps: taking a compound (E)-2-(2-nitrovinyl) isoindoline-1,3-diketone and ethyl pyruvate as initial raw materials, and carrying out Michael addition reaction under the condition of catalysis of a thiourea catalyst to obtain a corresponding Michael addition product; then, subjecting the Michael addition product and (formyl methylene) triphenyl phosphine to a Wittig reaction and a Henry reaction in a pot so as to obtain a ring closing product; and forming an etherified product from the ring closing product and a trichloroacetonitrile intermediate, and performing reduction, acetylation and de-protection to obtain oseltamivir. The reaction route comprises six steps, raw materials used in each step of reaction are easy to obtain and not expensive, the operation is easy, the yield of each step of reaction is high, no heavy metal or azide is used in the whole synthesis process, and the method is green and safe and can be applied to industrial production.
Hybrid Peptide-Thiourea Catalyst for Asymmetric Michael Additions of Aldehydes to Heterocyclic Nitroalkenes
?melová, Patrícia,Vargová, Denisa,?ebesta, Radovan
, p. 581 - 592 (2020/12/22)
Bifunctional organocatalysis combining covalent and noncovalent activation is presented. The hybrid peptide-thiourea catalyst features a N-terminal proline moiety for aldehyde activation and a thiourea unit for electrophile activation. This catalyst effec
Unified Synthesis of Polycyclic Alkaloids by Complementary Carbonyl Activation**
Christmann, Mathias,He, Guoli,List, Benjamin
supporting information, p. 13591 - 13596 (2021/05/07)
A complementary dual carbonyl activation strategy for the synthesis of polycyclic alkaloids has been developed. Successful applications include the synthesis of tetracyclic alkaloids harmalanine and harmalacinine, pentacyclic indoloquinolizidine alkaloid nortetoyobyrine, and octacyclic β-carboline alkaloid peganumine A. The latter synthesis features a protecting-group-free assembly and an asymmetric disulfonimide-catalyzed cyclization. Furthermore, formal syntheses of hirsutine, deplancheine, 10-desbromoarborescidine A, and oxindole alkaloids rhynchophylline and isorhynchophylline have been achieved. Finally, a concise synthesis of berberine alkaloid ilicifoline B was completed.
Highly Acidic Conjugate-Base-Stabilized Carboxylic Acids Catalyze Enantioselective oxa-Pictet–Spengler Reactions with Ketals
Zhu, Zhengbo,Odagi, Minami,Zhao, Chenfei,Abboud, Khalil A.,Kirm, Helmi Ulrika,Saame, Jaan,L?kov, M?rt,Leito, Ivo,Seidel, Daniel
, p. 2028 - 2032 (2019/12/24)
Acyclic ketone-derived oxocarbenium ions are involved as intermediates in numerous reactions that provide valuable products, however, they have thus far eluded efforts aimed at asymmetric catalysis. We report that a readily accessible chiral carboxylic acid catalyst exerts control over asymmetric cyclizations of acyclic ketone-derived trisubstituted oxocarbenium ions, thereby providing access to highly enantioenriched dihydropyran products containing a tetrasubstituted stereogenic center. The high acidity of the carboxylic acid catalyst, which exceeds that of the well-known chiral phosphoric acid catalyst TRIP, is largely derived from stabilization of the carboxylate conjugate base through intramolecular anion-binding to a thiourea site.
Catalyst Repurposing Sequential Catalysis by Harnessing Regenerated Prolinamide Organocatalysts as Transfer Hydrogenation Ligands
Bourgeois, Frederic,Medlock, Jonathan A.,Bonrath, Werner,Sparr, Christof
supporting information, p. 110 - 115 (2019/12/30)
A catalyst repurposing strategy based on a sequential aldol addition and transfer hydrogenation giving access to enantiomerically enriched α-hydroxy-γ-butyrolactones is described. The combination of a stereoselective, organocatalytic step, followed by an efficient catalytic aldehyde reduction induces an ensuing lactonization to provide enantioenriched butyrolactones from readily available starting materials. By capitalizing from the capacity of prolineamides to act as both an organocatalyst and a transfer hydrogenation ligand, catalyst repurposing allowed the development of an operationally simple, economic, and efficient sequential catalysis approach.
A conjugate Lewis base-Br?nsted acid catalyst for the sulfenylation of nitrogen containing heterocycles under mild conditions
Nalbandian, Christopher J.,Miller, Eric M.,Toenjes, Sean T.,Gustafson, Jeffery L.
supporting information, p. 1494 - 1497 (2017/02/05)
Catalysts that contain a thiourea tethered to a carboxylic acid were found to affect the sulfenylation of indoles and other N-heterocycles on the hour time scale at room temperature. The mild nature of these conditions allowed for the incorporation of diverse functionalities into more complex heterocycles.
Synthesis of pyrrolidine-3-carboxylic acid derivatives: Via asymmetric Michael addition reactions of carboxylate-substituted enones
Yin, Feng,Garifullina, Ainash,Tanaka, Fujie
supporting information, p. 6089 - 6092 (2017/08/02)
To concisely synthesize highly enantiomerically enriched 5-alkyl-substituted pyrrolidine-3-carboxylic acids, organocatalytic enantioselective Michael addition reactions of 4-alkyl-substituted 4-oxo-2-enoates with nitroalkanes have been developed. Using the developed reaction method, 5-methylpyrrolidine-3-carboxylic acid with 97% ee was obtained in two steps.
NEW PROCESS
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Page/Page column 61; 66, (2017/06/02)
The present invention relates to a new chemical synthesis, intermediates and catalysts useful for the preparation of the neprilysin (NEP) inhibitor sacubitril. It further relates to new intermediate compounds and their use for said new chemical synthesis
New simple primary amine-thiourea organocatalysts and their application in asymmetric conjugate addition
Yu, Lu,Li, Pengfei
supporting information, p. 3697 - 3700 (2014/06/23)
A kind of simple primary amine-thiourea organocatalysts was developed. And their application in asymmetric conjugate addition of ketone to nitroalkene was investigated. In the presence of the new primary amine-thiourea, the conjugate addition of ketone to
Enantioselective [4 + 2] cycloaddition of cyclic N-sulfimines and acyclic enones or ynones: A concise route to sulfamidate-fused 2,6-disubstituted piperidin-4-ones
Liu, Yong,Kang, Tai-Ran,Liu, Quan-Zhong,Chen, Lian-Mei,Wang, Ya-Chuan,Liu, Jie,Xie, Yong-Mei,Yang, Jin-Liang,He, Long
supporting information, p. 6090 - 6093 (2014/01/06)
A concise route to valuable sulfamate-fused 2,6-disubstituted piperidin-4-ones or 2,3-dihydropyridin-4(1H)-ones in good yield with high diastereo- and enantioselectivity is presented. The combination of chiral primary amine and o-fluorobenzoic acid efficiently promoted an asymmetric [4 + 2] cycloaddition reaction of N-sulfonylimines and enones or ynones. The cycloaddition reaction between cyclic N-sulfonylimines and ynones is first reported.
