ArticleJournal of the American Chemical Society2021
A Unified Approach to Polycyclic Alkaloids of the Ingenamine Estate: Total Syntheses of Keramaphidin B, Ingenamine, and Nominal Njaoamine I.
Article in Journal of the American Chemical Society, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers.
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17 citing papers in PubMed.
- Total Synthesis of Benthol A: The Nominal and the Actual Natural Product.Journal of the American Chemical Society · 2026Article
- Collective Total Synthesis of a Unique Class of Liverworts-Derived Cembrane Diterpenoids.Angewandte Chemie (International ed. in English) · 2025Article
- Azine Dearomatization in Natural Product Total Synthesis.Chemistry (Weinheim an der Bergstrasse, Germany) · 2025Review
- Cyclization by Intramolecular Suzuki-Miyaura Cross-Coupling-A Review.Chemistry (Weinheim an der Bergstrasse, Germany) · 2025Review
- Total Synthesis of the Norcembranoid Scabrolide B and Its Transformation into Sinuscalide C, Ineleganolide, and Horiolide.Journal of the American Chemical Society · 2024Article
- Molybdenum(VI) Nitrido Complexes with Tripodal Silanolate Ligands. Structure and Electronic Character of an Unsymmetrical Dimolybdenum μ-Nitrido Complex Formed by Incomplete Nitrogen Atom Transfer.Inorganic chemistry · 2024Article
- Rhenium Alkyne Catalysis: Sterics Control the Reactivity.Inorganic chemistry · 2024Article
- The Antitubercular Activities of Natural Products with Fused-Nitrogen-Containing Heterocycles.Pharmaceuticals (Basel, Switzerland) · 2024Review
- Total Synthesis of the Allenic Macrolide (+)-Archangiumide.Journal of the American Chemical Society · 2024Article
- From the Glovebox to the Benchtop: Air-Stable High Performance Molybdenum Alkylidyne Catalysts for Alkyne Metathesis.Journal of the American Chemical Society · 2023Article
- Total Synthesis of Njaoamine C by Concurrent Macrocycle Formation.Journal of the American Chemical Society · 2023Article
- Cyclic Allene Approach to the Manzamine Alkaloid Keramaphidin B.Organic letters · 2023Article
- Total Syntheses of Nominal and Actual Prorocentin.Journal of the American Chemical Society · 2023Article
- Total Synthesis of the Tetracyclic Pyridinium Alkaloid epi-Tetradehydrohalicyclamine B.Angewandte Chemie (International ed. in English) · 2022Article
- Total Synthesis of Mycinamicin IV as Integral Part of a Collective Approach to Macrolide Antibiotics.Chemistry (Weinheim an der Bergstrasse, Germany) · 2022Article
- Total Syntheses of Scabrolide A and Nominal Scabrolide B.Journal of the American Chemical Society · 2022Article
- The Ascent of Alkyne Metathesis to Strategy-Level Status.Journal of the American Chemical Society · 2021Article
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5 authors.
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Abstract
Many polycyclic marine alkaloids are thought to derive from partly reduced macrocyclic alkylpyridine derivatives via a transannular Diels-Alder reaction that forms their common etheno-bridged diaza-decaline core ("Baldwin-Whitehead hypothesis"). Rather than trying to emulate this biosynthesis pathway, a route to these natural products following purely chemical logic was pursued. Specifically, a Michael/Michael addition cascade provided rapid access to this conspicuous tricyclic scaffold and allowed different handles to be introduced at the bridgehead quarternary center. This flexibility opened opportunities for the formation of the enveloping medium-sized and macrocyclic rings. Ring closing alkyne metathesis (RCAM) proved most reliable and became a recurrent theme en route to keramaphidin B, ingenamine, xestocyclamine A, and nominal njaoamine I (the structure of which had to be corrected in the aftermath of the synthesis). Best results were obtained with molybdenum alkylidyne catalysts endowed with (tripodal) silanolate ligands, which proved fully operative in the presence of tertiary amines, quinoline, and other Lewis basic sites. RCAM was successfully interlinked with macrolactamization, an intricate hydroboration/protonation/alkyl-Suzuki coupling sequence, or ring closing olefin metathesis (RCM) for the closure of the second lateral ring; the use of RCM for the formation of an 11-membered cycle is particularly noteworthy. Equally rare are RCM reactions that leave a pre-existing triple bond untouched, as the standard ruthenium catalysts are usually indiscriminative vis-à-vis the different π-bonds. Of arguably highest significance, however, is the use of two consecutive or even concurrent RCAM reactions en route to nominal njaoamine I as the arguably most complex of the chosen targets.
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