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Rütter D, van Gastel M, Leutzsch M, Nöthling N, SantaLucia D, Neese F, Fürstner A. 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. Inorg Chem 2024; 63:8376-8389. [PMID: 38663089 PMCID: PMC11080062 DOI: 10.1021/acs.inorgchem.4c00762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 04/05/2024] [Accepted: 04/11/2024] [Indexed: 05/07/2024]
Abstract
In contrast to a tungsten nitrido complex endowed with a tripodal silanolate ligand framework, which was reported in the literature to be a dimeric species with a metallacyclic core, the corresponding molybdenum nitrides 3 are monomeric entities comprising a regular terminal nitride unit, as proven by single-crystal X-ray diffraction (SC-XRD). Their electronic character is largely determined by the constraints imposed on the metal center by the podand ligand architecture. 95Mo nuclear magnetic resonance (NMR) and, to a lesser extent, 14N NMR spectroscopy allow these effects to be studied, which become particularly apparent upon comparison with the spectral data of related molybdenum nitrides comprising unrestrained silanolate, alkoxide, or amide ligands. Attempted nitrogen atom transfer from these novel terminal nitrides to [(tBuArN)3Mo] (Ar = 3,5-dimethylphenyl) as the potential acceptor stopped at the stage of unsymmetric dimolybdenum μ-nitrido complex 13a as the first intermediate along the reaction pathway. SC-XRD, NMR, electron paramagnetic resonance, and ultraviolet-visible spectroscopy as well as magnetometry in combination with density functional theory allowed a clear picture of the geometric and electronic structure of this mixed-valent species to be drawn. 13a is formally best described as an adduct of the type [(Mo[O])+III-(μN)-III-(Mo[N])+VI], S = 1/2 complex with (Mo[O])+III in the low-spin configuration, whereas related complexes such as [(AdS)3Mo-(μN)-Mo(NtBuAr)3] (19; Ad = 1-adamantyl) have previously been regarded in the literature as mixed-valent Mo+IV/Mo+V species. The spin population at the two Mo centers is uneven and notably larger at the more reduced Mo[O] atom, whereas the only spin present at the (μN) bridge is derived from spin polarization.
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Affiliation(s)
- Daniel Rütter
- Max-Planck-Institut
für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | | | - Markus Leutzsch
- Max-Planck-Institut
für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Nils Nöthling
- Max-Planck-Institut
für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Daniel SantaLucia
- Max-Planck-Institut
für Chemische Energiekonversion, 45470 Mülheim/Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut
für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut
für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
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2
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Burton NR, Backus KM. Functionalizing tandem mass tags for streamlining click-based quantitative chemoproteomics. Commun Chem 2024; 7:80. [PMID: 38600184 PMCID: PMC11006884 DOI: 10.1038/s42004-024-01162-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 03/27/2024] [Indexed: 04/12/2024] Open
Abstract
Mapping the ligandability or potential druggability of all proteins in the human proteome is a central goal of mass spectrometry-based covalent chemoproteomics. Achieving this ambitious objective requires high throughput and high coverage sample preparation and liquid chromatography-tandem mass spectrometry analysis for hundreds to thousands of reactive compounds and chemical probes. Conducting chemoproteomic screens at this scale benefits from technical innovations that achieve increased sample throughput. Here we realize this vision by establishing the silane-based cleavable linkers for isotopically-labeled proteomics-tandem mass tag (sCIP-TMT) proteomic platform, which is distinguished by early sample pooling that increases sample preparation throughput. sCIP-TMT pairs a custom click-compatible sCIP capture reagent that is readily functionalized in high yield with commercially available TMT reagents. Synthesis and benchmarking of a 10-plex set of sCIP-TMT reveal a substantial decrease in sample preparation time together with high coverage and high accuracy quantification. By screening a focused set of four cysteine-reactive electrophiles, we demonstrate the utility of sCIP-TMT for chemoproteomic target hunting, identifying 789 total liganded cysteines. Distinguished by its compatibility with established enrichment and quantification protocols, we expect sCIP-TMT will readily translate to a wide range of covalent chemoproteomic applications.
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Affiliation(s)
- Nikolas R Burton
- Department of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles CA, USA
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA, USA
| | - Keriann M Backus
- Department of Biological Chemistry, David Geffen School of Medicine, UCLA, Los Angeles CA, USA.
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA, USA.
- Molecular Biology Institute, UCLA, Los Angeles, CA, USA.
- DOE Institute for Genomics and Proteomics, UCLA, Los Angeles, CA, USA.
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, CA, USA.
- Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA, USA.
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3
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Zhang H, Li X, Hui Z, Huang S, Cai M, Shi W, Lin Y, Shen J, Sui M, Lai Q, Shao Z, Dou J, Luo X, Ge Y, Tang X. A Semisynthesis Platform for the Efficient Production and Exploration of Didemnin-Based Drugs. Angew Chem Int Ed Engl 2024; 63:e202318784. [PMID: 38291557 DOI: 10.1002/anie.202318784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/28/2024] [Accepted: 01/30/2024] [Indexed: 02/01/2024]
Abstract
Plitidepsin (or dehydrodidemnin B), an approved anticancer drug, belongs to the didemnin family of cyclic depsipeptides, which are found in limited quantities in marine tunicate extracts. Herein, we introduce a new approach that integrates microbial and chemical synthesis to generate plitidepsin and its analogues. We screened a Tistrella strain library to identify a potent didemnin B producer, and then introduced a second copy of the didemnin biosynthetic gene cluster into its genome, resulting in a didemnin B titer of approximately 75 mg/L. Next, we developed two straightforward chemical strategies to convert didemnin B into plitidepsin, one of which involved a one-step synthetic route giving over 90 % overall yield. Furthermore, we synthesized 13 new didemnin derivatives and three didemnin probes, enabling research into structure-activity relationships and interactions between didemnin and proteins. Our study highlights the synergistic potential of biosynthesis and chemical synthesis in overcoming the challenge of producing complex natural products sustainably and at scale.
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Affiliation(s)
- Haili Zhang
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
| | - Xuyang Li
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
| | - Zhen Hui
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
| | - Shipeng Huang
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
- Department of Chemistry and Shenzhen Grubbs Institute, Southern University of Science and Technology, 518000, Shenzhen, China
| | - Mingwei Cai
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
| | - Wenguang Shi
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
| | - Yang Lin
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
| | - Jie Shen
- College of Life Science and Technology, China Pharmaceutical University, 211198, Nanjing, China
| | - Minghao Sui
- College of Life Science and Technology, China Pharmaceutical University, 211198, Nanjing, China
| | - Qiliang Lai
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, 184 Daxue Road, 361005, Xiamen, China
| | - Zongze Shao
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, 184 Daxue Road, 361005, Xiamen, China
| | - Jie Dou
- College of Life Science and Technology, China Pharmaceutical University, 211198, Nanjing, China
| | - Xiaozhou Luo
- Center for Synthetic Biochemistry, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 518055, Shenzhen, China
| | - Yun Ge
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
- State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, 518055, Shenzhen, China
| | - Xiaoyu Tang
- Institute of Chemical Biology, Shenzhen Bay Laboratory, 518132, Shenzhen, China
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4
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Lin B, Liu T, Luo T. Gold-catalyzed cyclization and cycloaddition in natural product synthesis. Nat Prod Rep 2024. [PMID: 38456472 DOI: 10.1039/d3np00056g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
Covering: 2016 to mid 2023Transition metal catalysis, known for its remarkable capacity to expedite the assembly of molecular complexity from readily available starting materials in a single operation, occupies a central position in contemporary chemical synthesis. Within this landscape, gold-catalyzed reactions present a novel and versatile paradigm, offering robust frameworks for accessing diverse structural motifs. In this review, we highlighted a curated selection of publications in the past 8 years, focusing on the deployment of homogeneous gold catalysis in the ring-forming step for the total synthesis of natural products. These investigations are categorized based on the specific ring formations they engender, accentuating the prevailing gold-catalyzed methodologies applied to surmount intricate challenges in natural products synthesis.
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Affiliation(s)
- Boxu Lin
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
| | - Tianran Liu
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
| | - Tuoping Luo
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, Guangdong 518055, China
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5
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Yahata K, Fürstner A. Total Synthesis of the Guangnanmycin A Alcohol. Angew Chem Int Ed Engl 2024; 63:e202319070. [PMID: 38226793 DOI: 10.1002/anie.202319070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/14/2024] [Accepted: 01/16/2024] [Indexed: 01/17/2024]
Abstract
Guangnanmycin A is a recently discovered congener of the well-known antitumor drug lead leinamycin; its macrolactam ring, however, is even more strained than that of the parent compound. The first synthetic foray towards this challenging target is reported, which relies on molybdenum-catalyzed macrocyclization by ring closing alkyne metathesis (RCAM) followed by ruthenium-catalyzed redox isomerization of the propargyl alcohol thus formed; the resulting enone enabled the introduction of the yet missing exo-methylene group by a modified Peterson olefination. The signature disulfide moiety of guangnanmycin A was installed by strain-driven thia-Michael addition followed by conversion of the thioether thus formed into an unsymmetric disulfide with the aid of (methylthio)dimethylsulfonium tetrafluoroborate and MeSSMe. While this sequence furnished racemic guangnanmycin A alcohol in good overall yield, the final oxidation to the corresponding acid failed, most likely because of the exceptional sensitivity of the strained scaffold.
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Affiliation(s)
- Kenzo Yahata
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
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6
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Bracken AK, Gekko CE, Suss NO, Lueders EE, Cui Q, Fu Q, Lui ACW, Anderson ET, Zhang S, Abbasov ME. Biomimetic Synthesis and Chemical Proteomics Reveal the Mechanism of Action and Functional Targets of Phloroglucinol Meroterpenoids. J Am Chem Soc 2024; 146:2524-2548. [PMID: 38230968 PMCID: PMC11000255 DOI: 10.1021/jacs.3c10741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Natural products perennially serve as prolific sources of drug leads and chemical probes, fueling the development of numerous therapeutics. Despite their scarcity, natural products that modulate protein function through covalent interactions with lysine residues hold immense potential to unlock new therapeutic interventions and advance our understanding of the biological processes governed by these modifications. Phloroglucinol meroterpenoids constitute one of the most expansive classes of natural products, displaying a plethora of biological activities. However, their mechanism of action and cellular targets have, until now, remained elusive. In this study, we detail the concise biomimetic synthesis, computational mechanistic insights, physicochemical attributes, kinetic parameters, molecular mechanism of action, and functional cellular targets of several phloroglucinol meroterpenoids. We harness synthetic clickable analogues of natural products to probe their disparate proteome-wide reactivity and subcellular localization through in-gel fluorescence scanning and cell imaging. By implementing sample multiplexing and a redesigned lysine-targeting probe, we streamline a quantitative activity-based protein profiling, enabling the direct mapping of global reactivity and ligandability of proteinaceous lysines in human cells. Leveraging this framework, we identify numerous lysine-meroterpenoid interactions in breast cancer cells at tractable protein sites across diverse structural and functional classes, including those historically deemed undruggable. We validate that phloroglucinol meroterpenoids perturb biochemical functions through stereoselective and site-specific modification of lysines in proteins vital for breast cancer metabolism, including lipid signaling, mitochondrial respiration, and glycolysis. These findings underscore the broad potential of phloroglucinol meroterpenoids for targeting functional lysines in the human proteome.
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Affiliation(s)
- Amy K Bracken
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Colby E Gekko
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Nina O Suss
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Emma E Lueders
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Qi Cui
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Qin Fu
- Proteomics and Metabolomics Facility, Cornell University, Ithaca, New York 14853, United States
| | - Andy C W Lui
- Proteomics and Metabolomics Facility, Cornell University, Ithaca, New York 14853, United States
| | - Elizabeth T Anderson
- Proteomics and Metabolomics Facility, Cornell University, Ithaca, New York 14853, United States
| | - Sheng Zhang
- Proteomics and Metabolomics Facility, Cornell University, Ithaca, New York 14853, United States
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7
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Sutro JL, Fürstner A. Total Synthesis of the Allenic Macrolide (+)-Archangiumide. J Am Chem Soc 2024; 146:2345-2350. [PMID: 38241031 PMCID: PMC10835656 DOI: 10.1021/jacs.3c13304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/07/2024] [Accepted: 01/11/2024] [Indexed: 02/01/2024]
Abstract
Archangiumide is the first known macrolide natural product comprising an endocyclic allene. For the ring strain that this linear substructure might entail, it was planned to unveil the allene at a very late stage of the projected total synthesis; in actual fact, this was achieved as the last step of the longest linear sequence by using an otherwise globally deprotected substrate. This unconventional timing was made possible by a gold catalyzed rearrangement of a macrocyclic propargyl benzyl ether derivative that uses a -PMB group as latent hydride source to unveil the signature cycloallene; the protecting group therefore gains a strategic role beyond its mere safeguarding function. Although the gold catalyzed reaction per se is stereoablative, the macrocyclic frame of the target was found to impose high selectivity and a stereoconvergent character on the transformation. The required substrate was formed by ring closing alkyne metathesis (RCAM) with the aid of a new air-stable molybdenum alkylidyne catalyst.
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Affiliation(s)
- Jack L. Sutro
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
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8
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Chiu TY, Lazar DC, Wang WW, Wozniak JM, Jadhav AM, Li W, Gazaniga N, Theofilopoulos AN, Teijaro JR, Parker CG. Chemoproteomic development of SLC15A4 inhibitors with anti-inflammatory activity. Nat Chem Biol 2024:10.1038/s41589-023-01527-8. [PMID: 38191941 PMCID: PMC11228132 DOI: 10.1038/s41589-023-01527-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 12/14/2023] [Indexed: 01/10/2024]
Abstract
SLC15A4 is an endolysosome-resident transporter linked with autoinflammation and autoimmunity. Specifically, SLC15A4 is critical for Toll-like receptors (TLRs) 7-9 as well as nucleotide-binding oligomerization domain-containing protein (NOD) signaling in several immune cell subsets. Notably, SLC15A4 is essential for the development of systemic lupus erythematosus in murine models and is associated with autoimmune conditions in humans. Despite its therapeutic potential, the availability of quality chemical probes targeting SLC15A4 functions is limited. In this study, we used an integrated chemical proteomics approach to develop a suite of chemical tools, including first-in-class functional inhibitors, for SLC15A4. We demonstrate that these inhibitors suppress SLC15A4-mediated endolysosomal TLR and NOD functions in a variety of human and mouse immune cells; we provide evidence of their ability to suppress inflammation in vivo and in clinical settings; and we provide insights into their mechanism of action. Our findings establish SLC15A4 as a druggable target for the treatment of autoimmune and autoinflammatory conditions.
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Affiliation(s)
- Tzu-Yuan Chiu
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Daniel C Lazar
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Wesley W Wang
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Jacob M Wozniak
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Appaso M Jadhav
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Weichao Li
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Nathalia Gazaniga
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | | | - John R Teijaro
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA.
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9
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Korber JN, Wille C, Leutzsch M, Fürstner A. From the Glovebox to the Benchtop: Air-Stable High Performance Molybdenum Alkylidyne Catalysts for Alkyne Metathesis. J Am Chem Soc 2023; 145:26993-27009. [PMID: 38032858 PMCID: PMC10722517 DOI: 10.1021/jacs.3c10430] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 12/02/2023]
Abstract
Molybdenum alkylidynes endowed with tripodal silanolate ligands belong to the most active and selective catalysts for alkyne metathesis known to date. This paper describes a new generation that is distinguished by an unprecedented level of stability and practicality without sacrificing the chemical virtues of their predecessors. Specifically, pyridine adducts of type 16 are easy to make on gram scale, can be routinely weighed and handled in air, and stay intact for many months outside the glovebox. When dissolved in toluene, however, spontaneous dissociation of the stabilizing pyridine ligand releases an active species of excellent performance and functional group tolerance. Specifically, a host of polar and apolar groups, various protic sites, and numerous basic functionalities proved compatible. The catalysts are characterized by crystallographic and spectroscopic means, including 95Mo NMR; their activity and stability are benchmarked in detail, and the enabling properties are illustrated by advanced applications to natural product synthesis. For the favorable overall application profile and ease of handling, complexes of this new series are expected to replace earlier catalyst generations and help encourage a more regular use of alkyne metathesis in general.
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Affiliation(s)
- J. Nepomuk Korber
- Max-Planck-Institut
für Kohlenforschung, D-45470 Mülheim/Ruhr, Germany
| | - Christian Wille
- Max-Planck-Institut
für Kohlenforschung, D-45470 Mülheim/Ruhr, Germany
| | - Markus Leutzsch
- Max-Planck-Institut
für Kohlenforschung, D-45470 Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut
für Kohlenforschung, D-45470 Mülheim/Ruhr, Germany
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10
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Rossouw NP, Chen Z, White JM, Rizzacasa MA. Synthesis of More Highly Oxidized Alkyl Citrates via Direct Regio- and Stereoselective Oxidation. Org Lett 2023; 25:8010-8015. [PMID: 37916764 DOI: 10.1021/acs.orglett.3c03232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
An approach to more highly oxidized alkyl citrates by direct regio- and stereoselective oxidations is reported. The total synthesis and structural assignment of alkyl citrate L-731-128 are described, and the synthesis of its C4 oxidized congener L-731,127 utilized a regio- and stereoselective enolate oxidation with oxygen gas. A highly stereoselective Rubottom oxidation of a cyclic silylketene acetal then enabled oxidation at C2 to afford the cinatrins C1 and C3.
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Affiliation(s)
- Nikolai P Rossouw
- School of Chemistry, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Zongjia Chen
- School of Chemistry, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Jonathan M White
- School of Chemistry, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Mark A Rizzacasa
- School of Chemistry, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
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11
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Crunkhorn S. Synthesizing portimines. Nat Rev Drug Discov 2023; 22:873. [PMID: 37798467 DOI: 10.1038/d41573-023-00161-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
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12
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Varlet T, Portmann S, Fürstner A. Total Synthesis of Njaoamine C by Concurrent Macrocycle Formation. J Am Chem Soc 2023; 145:21197-21202. [PMID: 37734001 PMCID: PMC10557140 DOI: 10.1021/jacs.3c08410] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Indexed: 09/23/2023]
Abstract
In conceptual terms, the first total synthesis of the cytotoxic marine natural product njaoamine C differs from all known approaches toward related alkaloids of the manzamine superfamily in that both macrocyclic rings enveloping the diazatricyclic core are concomitantly formed; this goal was reached by double ring closing alkyne metathesis (dRCAM). The success of this maneuver does not merely reflect a favorable preorientation of the four alkyne chains that need to be concatenated in the proper pairwise manner but is also the outcome of dynamic covalent chemistry involving error correction by the chosen "canopy" molybdenum alkylidyne catalyst. The end game downstream of dRCAM capitalizes on the striking chemoselectivity of palladium-catalyzed hydrostannation, which selects for (hetero)arylalkynes even in the presence of sterically much more accessible dialkylalkynes or alkenes; for this preference, the method complements the classical repertoire of hydrometalation and semireduction reactions.
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Affiliation(s)
- Thomas Varlet
- Max-Planck-Institut für
Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Sören Portmann
- Max-Planck-Institut für
Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für
Kohlenforschung, 45470 Mülheim/Ruhr, Germany
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