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The development of a concise total synthesis of (±)‐phyllantidine (1), a member of the securinega family of alkaloids containing an unusual oxazabicyclo[3.3.1]nonane core, is described. The synthesis employs a unique synthetic strategy featuring the ring expansion of a substituted cyclopentanone to a cyclic hydroxamic acid as a key step that allows facile installation of the embedded nitrogen‐oxygen (N−O) bond. The optimization of this sequence to effect the desired regiochemical outcome and its mechanistic underpinnings were assessed both computationally and experimentally. This synthetic approach also features an early‐stage diastereoselective aldol reaction to assemble the substituted cyclopentanone, a mild reduction of an amide intermediate without N−O bond cleavage, and the rapid assembly of the butenolide found in (1) via use of the Bestmann ylide. [ABSTRACT FROM AUTHOR]

Abstract: Described herein is a concise total synthesis of the highly potent nicotinic acetylcholine receptor ligand hosieine A in racemic and enantioenriched forms. The synthesis requires only seven steps and features a telescoped reaction sequence initiated by a gold‐catalyzed Rautenstrauch reaction. [ABSTRACT FROM AUTHOR]

Abstract: Described herein is a synthetic strategy for the total synthesis of (±)‐phomoidride D. This highly efficient and stereoselective approach provides rapid assembly of the carbocyclic core by way of a tandem phenolic oxidation/intramolecular Diels–Alder cycloaddition. A subsequent SmI2‐mediated cyclization cascade delivers an isotwistane intermediate poised for a Wharton fragmentation that unveils the requisite bicyclo[4.3.1]decene skeleton and sets the stage for synthesis completion. [ABSTRACT FROM AUTHOR]

Abstract: Total syntheses of (+)-norsecurinine and (+)-allonorsecurinine are described that utilize a rhodium carbenoid-initiated O–H insertion/Claisen rearrangement/1,2-allyl migration domino process for the stereoselective introduction of the tertiary alcohol moiety. Overall the employed strategy is flexible and will allow access to other members of the Securinega family of alkaloids. [Copyright &y& Elsevier]

Abstract: The first total syntheses of (−)-syringolide 3, (+)-syributin 3 and their unnatural enantiomers (+)-syringolide 3 and (−)-syributin 3 using a common intermediate as starting material are described. In addition, total syntheses of (−)- and (+)-syributins 1 and 2 were accomplished by means of the same methodology. [Copyright &y& Elsevier]

[Display omitted] • Natural product inspires the application of allene ether Nazarov Chemistry. • Torquoselectivity guides the stereochemical course in allene ether Nazarov Reaction. • Palladium precatalyst greatly improves efficiency in an enol triflate to ene-amide conversion. This manuscript describes progress towards the total synthesis of (±)-isopalhinine A wherein an allene ether Nazarov cyclization gives rise to the bicyclic core. [ABSTRACT FROM AUTHOR]

Abstract Described is a total synthesis of the related alkaloids, cyclopiamide A and speradine E, via a unified strategy that also delivers the natural product aspergilline A. Key steps include metal-free conversion of a malonyl chloride and propargylamine to an intermediate pyrrolinone and a palladium catalyzed decarboxylation/aromatization sequence that delivers the requisite tetracyclic core. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]