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.
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.
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.
