1
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Yu L, Nagata Y, Nakamura H. Atroposelective Total Synthesis of Cihunamide B. J Am Chem Soc 2024; 146:2549-2555. [PMID: 38240691 DOI: 10.1021/jacs.3c11016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
A short, atroposelective synthesis of cihunamide B (1) is reported. The feature of this report is the decagram-scale SNAr reaction of l-tryptophan derivatives, followed by atroposelective Larock macrocyclization. This strategy allowed the construction of a Trp-Trp cross-linkage with unprecedented atropisomerism. The atroposelectivity of this Larock macrocyclization has been investigated through a combination of experimental and computational chemistry, yielding detailed insights into the synthesis of biaryl linkages. It also enabled the concise synthesis of cihunamide B (1), which is expected to be a potential antibacterial agent.
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Affiliation(s)
- Longhui Yu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong 999077, China
| | - Yuuya Nagata
- WPI Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
| | - Hugh Nakamura
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong 999077, China
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2
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Thangsan P, Rukkijakan T, Thanaussavadate B, Yiamsawat K, Sirijaraensre J, Gable KP, Chuawong P. Quantitative analysis of steric effects on the regioselectivity of the Larock heteroannulation reaction. Org Biomol Chem 2023; 21:1501-1513. [PMID: 36688538 DOI: 10.1039/d2ob02089k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Alkylphenylacetylene derivatives were synthesized and used as reactants in the Larock heteroannulation reaction to investigate the steric influence on regioselectivity. Large alkyl groups preferentially yielded 2-alkyl-3-phenylindole products, while smaller alkyl groups provided 3-alkyl-2-phenylindole as major products. The logarithm of regioisomeric product ratios exhibited good correlations with various steric parameters. Notably, the Charton values provided the best correlation when excluding the cyclopropyl group. In addition, the Boltzmann-weighted Sterimol parameter (wSterimol) was utilized to generate a good predictive model, indicating the B1 wSterimol as the significant regiochemical determining parameter with no obvious deviation for the cyclopropyl group. Relative atomic distances within the DFT-optimized transition state structures revealed good correlations with the logarithm of regioisomeric ratios. Furthermore, the cyclopropyl adsorption complex indicated electronic contribution, explaining the peculiar behavior of this substituent in the experimental observation.
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Affiliation(s)
- Poomsith Thangsan
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Thanya Rukkijakan
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Bongkotrat Thanaussavadate
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Kanyapat Yiamsawat
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
| | - Jakkapan Sirijaraensre
- Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
| | - Kevin P Gable
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331-4003, USA
| | - Pitak Chuawong
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand.
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3
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Li X, Ma S, Zhang Q. Chemical Synthesis and Biosynthesis of Darobactin. Tetrahedron Lett 2023. [DOI: 10.1016/j.tetlet.2023.154337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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4
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Abstract
Ribosomally synthesized and post-translationally modified peptides (RiPPs) are known for their macrocyclic structures, which impart unique biological activity. One rapidly emerging subclass of RiPP natural products contains macrocyclic C-C cross-links between two amino acid side chains. These linkages, often biosynthetically formed by a single rSAM or P450 enzyme, introduce significant structural and synthetic complexity to the molecules. While nature utilizes elegant mechanisms to produce C-C cross-linked RiPPs, synthetic tools are only able to access a portion of these biologically relevant natural products. This review provides an overview of the structures in this subclass as well as a discussion on their chemical syntheses.
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Affiliation(s)
- David Laws
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Eleda V Plouch
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Simon B Blakey
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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5
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Lin YC, Schneider F, Eberle KJ, Chiodi D, Nakamura H, Reisberg SH, Chen J, Saito M, Baran PS. Atroposelective Total Synthesis of Darobactin A. J Am Chem Soc 2022; 144:14458-14462. [PMID: 35926121 PMCID: PMC9829381 DOI: 10.1021/jacs.2c05892] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A concise, modular synthesis of the novel antibiotic darobactin A is disclosed. The synthesis successfully forges the hallmark strained macrocyclic ring systems in a sequential fashion. Key transformations include two atroposelective Larock-based macrocyclizations, one of which proceeds with exquisite regioselectivity despite bearing an unprotected alkyne. The synthesis is designed with medicinal chemistry considerations in mind, appending key portions of the molecule at a late stage. Requisite unnatural amino acid building blocks are easily prepared in an enantiopure form using C-H activation and decarboxylative cross-coupling tactics.
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Affiliation(s)
- You-Chen Lin
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Fabian Schneider
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Kelly J Eberle
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Debora Chiodi
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Hugh Nakamura
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Solomon H Reisberg
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Jason Chen
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Masato Saito
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Phil S Baran
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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6
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Yiamsawat K, Gable KP, Chuawong P. Dissecting the Electronic Contribution to the Regioselectivity of the Larock Heteroannulation Reaction in the Oxidative Addition and Carbopalladation Steps. J Org Chem 2022; 87:1218-1229. [PMID: 34989564 DOI: 10.1021/acs.joc.1c02560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Substituted 2-iodoaniline derivatives were prepared and utilized as reactants, along with asymmetric diarylacetylenes, to synthesize a series of 6-substituted-2,3-diarylindole derivatives via the Larock heteroannulation reaction. Electron-donating substituents on the 2-iodoaniline derivatives retarded the reaction, while electron-withdrawing substituents provided a complete conversion to the indole products. In addition, the electronic properties of the substituted 2-iodoaniline reactants displayed no influence toward regioselectivity. On the contrary, the electronic effect from unsymmetrical diarylacetylenes significantly influenced the regiochemical outcome of the reaction. Density functional theory calculations of the oxidative addition and carbopalladation steps revealed the electronic influences of the substituted 2-iodoaniline derivatives toward the overall rate of the reaction. In contrast, the electronic properties of the asymmetric diarylacetylene remained the critical product-determining factor of regioselectivity.
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Affiliation(s)
- Kanyapat Yiamsawat
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand
| | - Kevin P Gable
- Department of Chemistry, Oregon State University, 153 Gilbert Hall, Corvallis, Oregon 97331-4003, United States
| | - Pitak Chuawong
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Special Research Unit for Advanced Magnetic Resonance (AMR), Kasetsart University, Bangkok 10900, Thailand
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7
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Heravi MM, Amiri Z, Kafshdarzadeh K, Zadsirjan V. Synthesis of indole derivatives as prevalent moieties present in selected alkaloids. RSC Adv 2021; 11:33540-33612. [PMID: 35497516 PMCID: PMC9042329 DOI: 10.1039/d1ra05972f] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 09/10/2021] [Indexed: 02/02/2023] Open
Abstract
Indoles are a significant heterocyclic system in natural products and drugs. They are important types of molecules and natural products and play a main role in cell biology. The application of indole derivatives as biologically active compounds for the treatment of cancer cells, microbes, and different types of disorders in the human body has attracted increasing attention in recent years. Indoles, both natural and synthetic, show various biologically vital properties. Owing to the importance of this significant ring system, the investigation of novel methods of synthesis have attracted the attention of the chemical community. In this review, we aim to highlight the construction of indoles as a moiety in selected alkaloids.
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Affiliation(s)
- Majid M Heravi
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Zahra Amiri
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Kosar Kafshdarzadeh
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Vahideh Zadsirjan
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
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8
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Swain JA, Walker SR, Calvert MB, Brimble MA. The tryptophan connection: cyclic peptide natural products linked via the tryptophan side chain. Nat Prod Rep 2021; 39:410-443. [PMID: 34581375 DOI: 10.1039/d1np00043h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Covering: from 1938 up to March 2021The electron-rich indole side chain of tryptophan is a versatile substrate for peptide modification. Upon the action of various cyclases, the tryptophan side chain may be linked to a nearby amino acid residue, opening the door to a diverse range of cyclic peptide natural products. These compounds exhibit a wide array of biological activity and possess fascinating molecular architectures, which have made them popular targets for total synthesis studies. This review examines the isolation and bioactivity of tryptophan-linked cyclic peptide natural products, along with a discussion of their first total synthesis, and biosynthesis where this has been studied.
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Affiliation(s)
- Jonathan A Swain
- School of Chemical Sciences, The University of Auckland, Symonds Street, Auckland 1010, New Zealand.
| | - Stephen R Walker
- School of Chemical Sciences, The University of Auckland, Symonds Street, Auckland 1010, New Zealand.
| | - Matthew B Calvert
- School of Chemical Sciences, The University of Auckland, Symonds Street, Auckland 1010, New Zealand.
| | - Margaret A Brimble
- School of Chemical Sciences, The University of Auckland, Symonds Street, Auckland 1010, New Zealand. .,Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Symonds Street, Auckland 1010, New Zealand
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9
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Abstract
Biomimetic natural product synthesis is generally straightforward and efficient because of its established feasibility in nature and utility in comprehensive synthesis, and the cost-effectiveness of naturally derived starting materials. On the other hand, nonbiomimetic strategies can be an important option in natural product synthesis since (1) nonbiomimetic synthesis offers more flexibility and can demonstrate the originality of chemists, and (2) the structures of derivatives accessible by nonbiomimetic synthesis can be considerably different from those that are synthesised in nature. This review summarises nonbiomimetic total syntheses of indole alkaloids using alkyne chemistry for constructing core structures, including ergot alkaloids, monoterpene indole alkaloids (mainly corynanthe, aspidosperma, strychnos, and akuammiline), and pyrroloindole and related alkaloids. To clarify the differences between alkyne-based strategies and biosynthesis, the alkynes in nature and the biosyntheses of indole alkaloids are also outlined.
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Affiliation(s)
- Hiroaki Ohno
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Shinsuke Inuki
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
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10
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Abstract
Peptide macrocyclization has traditionally relied on lactam, lactone and disulfide bond-forming reactions that aim at introducing conformational constraints into small peptide sequences. With the advent of ruthenium-catalyzed ring-closing metathesis and copper-catalyzed alkyne-azide cycloaddition, peptide chemists embraced transition metal catalysis as a powerful macrocyclization tool with relevant applications in chemical biological and peptide drug discovery. This article provides a comprehensive overview of the reactivity and methodological diversification of metal-catalyzed peptide macrocyclization as a special class of late-stage peptide derivatization method. We report the evolution from classic palladium-catalyzed cross-coupling approaches to more modern oxidative versions based on C-H activation, heteroatom alkylation/arylation and annulation processes, in which aspects such as chemoselectivity and diversity generation at the ring-closing moiety became dominant over the last years. The transit from early cycloadditions and alkyne couplings as ring-closing steps to very recent 3d metal-catalyzed macrocyclization methods is highlighted. Similarly, the new trends in decarboxylative radical macrocyclizations and the interplay between photoredox and transition metal catalysis are included. This review charts future perspectives in the field hoping to encourage further progress and applications, while bringing attention to the countless possibilities available by diversifying not only the metal, but also the reactivity modes and tactics to bring peptide functional groups together and produce structurally diverse macrocycles.
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Affiliation(s)
- Daniel G Rivera
- Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), Department of Chemistry, University of Leuven (KU Leuven), Celestijnenlaan 200F, B-3001 Leuven, Belgium. and Center for Natural Product Research, Faculty of Chemistry, University of Havana, Zapata y G, Havana 10400, Cuba.
| | - Gerardo M Ojeda-Carralero
- Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), Department of Chemistry, University of Leuven (KU Leuven), Celestijnenlaan 200F, B-3001 Leuven, Belgium. and Center for Natural Product Research, Faculty of Chemistry, University of Havana, Zapata y G, Havana 10400, Cuba.
| | - Leslie Reguera
- Center for Natural Product Research, Faculty of Chemistry, University of Havana, Zapata y G, Havana 10400, Cuba.
| | - Erik V Van der Eycken
- Laboratory for Organic & Microwave-Assisted Chemistry (LOMAC), Department of Chemistry, University of Leuven (KU Leuven), Celestijnenlaan 200F, B-3001 Leuven, Belgium. and Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Street 6, 117198 Moscow, Russia
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11
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Abstract
Since its discovery, vancomycin has been used in the clinic for >60 years. Because of their durability, vancomycin and related glycopeptides serve as the antibiotics of last resort for the treatment of protracted bacterial infections of resistant Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant (MDR) Streptococcus pneumoniae. After 30 years of use, vancomycin resistance was first observed and is now widespread in enterococci and more recently in S. aureus. The widespread prevalence of vancomycin-resistant enterococci (VRE) and the emergence of vancomycin-resistant S. aureus (VRSA) represent a call to focus on the challenge of resistance, highlight the need for new therapeutics, and provide the inspiration for the design of more durable antibiotics less prone to bacterial resistance than even vancomycin.Herein we summarize progress on efforts to overcome vancomycin resistance, first addressing recovery of its original durable mechanism of action and then introducing additional independent mechanisms of action intended to increase the potency and durability beyond that of vancomycin itself. The knowledge of the origin of vancomycin resistance and an understanding of the molecular basis of the loss of binding affinity between vancomycin and the altered target ligand d-Ala-d-Lac provided the basis for the subtle and rational redesign of the vancomycin binding pocket to remove the destabilizing lone-pair repulsion or reintroduce a lost H-bond while not impeding binding to the unaltered ligand d-Ala-d-Ala. Preparation of the modified glycopeptide core structure was conducted by total synthesis, providing binding pocket-modified vancomycin aglycons with dual d-Ala-d-Ala/d-Lac binding properties that directly address the intrinsic mechanism of resistance to vancomycin. Fully glycosylated pocket-modified vancomycin analogues were generated through a subsequent two-step enzymatic glycosylation, providing a starting point for peripheral modifications used to introduce additional mechanisms of action. A well-established vancosamine N-(4-chlorobiphenyl)methyl (CBP) modification as well as newly discovered C-terminal trimethylammonium cation (C1) or guanidine modifications were introduced, providing two additional synergistic mechanisms of action independent of d-Ala-d-Ala/d-Lac binding. The CBP modification provides an additional stage for inhibition of cell wall synthesis that results from direct competitive inhibition of transglycosylase, whereas the C1/guanidine modification induces bacteria cell permeablization. The synergistic behavior of the three independent mechanisms of action combined in a single molecule provides ultrapotent antibiotics (MIC = 0.01-0.005 μg/mL against VanA VRE). Beyond the remarkable antimicrobial activity, the multiple mechanisms of action suppress the rate at which resistance may be selected, where any single mechanism of action is protected by the action of others. The results detailed herein show that rational targeting of durable vancomycin-derived antibiotics has generated compounds with a "resistance against resistance", provided new candidate antibiotics, and may serve as a generalizable strategy to combat antibacterial resistance.
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Affiliation(s)
- Zhi-Chen Wu
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L. Boger
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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12
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Cheng C, Zuo X, Tu D, Wan B, Zhang Y. Synthesis of 3,4-Fused Tricyclic Indoles through Cascade Carbopalladation and C-H Amination: Development and Total Synthesis of Rucaparib. Org Lett 2020; 22:4985-4989. [PMID: 32610935 DOI: 10.1021/acs.orglett.0c01513] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
3,4-Fused tricyclic indole scaffolds are ubiquitous in bioactive natural products and pharmaceuticals. A new protocol for the synthesis of 3,4-fused tricyclic indoles has been developed through cascade carbopalladation and C-H amination with N,N-di-tert-butyldiaziridinone. The protocol allows access to a range of 3,4-fused tricyclic indoles, including those containing various linkers and fused with medium-sized rings. Rucaparib can be synthesized via this reaction, providing an advantageous synthetic method for the FDA-approved cancer medicine.
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Affiliation(s)
- Cang Cheng
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road, Shanghai 200092, China
| | - Xiang Zuo
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road, Shanghai 200092, China
| | - Dongdong Tu
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road, Shanghai 200092, China
| | - Bin Wan
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road, Shanghai 200092, China
| | - Yanghui Zhang
- School of Chemical Science and Engineering, Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University 1239 Siping Road, Shanghai 200092, China
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13
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Fan L, Hao J, Yu J, Ma X, Liu J, Luan X. Hydroxylamines As Bifunctional Single-Nitrogen Sources for the Rapid Assembly of Diverse Tricyclic Indole Scaffolds. J Am Chem Soc 2020; 142:6698-6707. [PMID: 32182059 DOI: 10.1021/jacs.0c00403] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Conventional approaches on using hydroxylamine derivatives as single nitrogen sources, for the construction of n-membered (n > 3) N-heterocycles, rely upon two chemical operations by involving sequential nucleophilic and electrophilic C-N bond formations. Here, we report a highly efficient cascade of alkyne insertion/C-H activation/amination for the rapid preparation of a myriad of tricyclic indoles, in a single-step transformation, by using bifunctional secondary hydroxylamines. It is noteworthy that judicious selection of applicable amino agents, for enabling the prior oxidative addition of aryl iodide to initial Pd(0) species and subsequent two C-N bonds formation, was the key to the success of this reaction. Control experiments indicated that a five-membered palladacyclic intermediate played a crucial role in promoting the final aminative ring closure.
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Affiliation(s)
- Liangxin Fan
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an 710127, P. R. China
| | - Jiamao Hao
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an 710127, P. R. China
| | - Jingxun Yu
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an 710127, P. R. China
| | - Xiaojun Ma
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an 710127, P. R. China
| | - Jingjing Liu
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an 710127, P. R. China
| | - Xinjun Luan
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an 710127, P. R. China
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14
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Wu ZC, Isley NA, Okano A, Weiss WJ, Boger DL. C1-CBP-vancomycin: Impact of a Vancomycin C-Terminus Trimethylammonium Cation on Pharmacological Properties and Insights into Its Newly Introduced Mechanism of Action. J Org Chem 2019; 85:1365-1375. [PMID: 31670958 DOI: 10.1021/acs.joc.9b02314] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
C1-CBP-vancomycin (3) was examined alongside CBP-vancomycin for susceptibility to acquired resistance upon serial exposure against two vancomycin-resistant enterococci strains where its activity proved more durable and remarkably better than many current therapies. Combined with earlier studies, this observation confirmed an added mechanism of action was introduced by incorporation of the trimethylammonium cation and that C1-CBP-vancomycin exhibits activity against vancomycin-resistant organisms through two synergistic mechanisms of action, both independent of d-Ala-d-Ala/d-Lac binding. New insights into this added mechanism of action, induced cell membrane permeabilization, can be inferred from studies that show added exogenous lipoteichoic acid reduces antimicrobial activity, rescues bacteria cell growth inhibition, and blocks induced cell permeabilization properties of C1-CBP-vancomycin, suggesting a direct binding interaction with embedded teichoic acid is responsible for the added mechanism of action and enhanced antimicrobial activity. Further studies indicate that the trimethylammonium cation does not introduce new liabilities in common pharmacological properties of the analogue and established that 3 is well tolerated in mice, displays substantial PK improvements over both vancomycin and CBP-vancomycin, and exhibits in vivo efficacy against a challenging multidrug-resistant and vancomycin-resistant S. aureus strain that is representative of the resistant pathogens all fear will emerge in the general population.
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Affiliation(s)
- Zhi-Chen Wu
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Nicholas A Isley
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Akinori Okano
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - William J Weiss
- University of North Texas System , College of Pharmacy , Fort Worth , Texas 76107 , United States
| | - Dale L Boger
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
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15
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Isley NA, Endo Y, Wu ZC, Covington BC, Bushin LB, Seyedsayamdost MR, Boger DL. Total Synthesis and Stereochemical Assignment of Streptide. J Am Chem Soc 2019; 141:17361-17369. [PMID: 31577142 DOI: 10.1021/jacs.9b09067] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Streptide (1) is a peptide-derived macrocyclic natural product that has attracted considerable attention since its discovery in 2015. It contains an unprecedented post-translational modification that intramolecularly links the β-carbon (C3) of a residue 2 lysine with the C7 of a residue 6 tryptophan, thereby forming a 20-membered cyclic peptide. Herein, we report the first total synthesis of streptide that confirms the regiochemistry of the lysine-tryptophan cross-link and provides an unambiguous assignment of the stereochemistry (3R vs 3S) of the lysine-2 C3 center. Both the 3R and the originally assigned 3S lysine diastereomers were independently prepared by total synthesis, and it is the former, not the latter, that was found to correlate with the natural product. The approach enlists a powerful Pd(0)-mediated indole annulation for the key macrocyclization of the complex core peptide, utilizes an underdeveloped class of hypervalent iodine(III) aryl substrates in a palladium-catalyzed C-H activation/β-arylation reaction conducted on a lysine derivative, and provides access to material with which the role of streptide and related natural products may be examined.
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Affiliation(s)
- Nicholas A Isley
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Yusuke Endo
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Zhi-Chen Wu
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Brett C Covington
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Leah B Bushin
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | | | - Dale L Boger
- Department of Chemistry and Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
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16
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Abstract
This Review is devoted to the chemistry of macrocyclic peptides having heterocyclic fragments in their structure. These motifs are present in many natural products and synthetic macrocycles designed against a particular biochemical target. Thiazole and oxazole are particularly common constituents of naturally occurring macrocyclic peptide molecules. This frequency of occurrence is because the thiazole and oxazole rings originate from cysteine, serine, and threonine residues. Whereas other heteroaryl groups are found less frequently, they offer many insightful lessons that range from conformational control to receptor/ligand interactions. Many options to develop new and improved technologies to prepare natural products have appeared in recent years, and the synthetic community has been pursuing synthetic macrocycles that have no precedent in nature. This Review attempts to summarize progress in this area.
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Affiliation(s)
- Ivan V Smolyar
- Department of Chemistry , Moscow State University , Leninskije Gory , 199991 Moscow , Russia
| | - Andrei K Yudin
- Davenport Research Laboratories, Department of Chemistry , University of Toronto , 80 St. George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Valentine G Nenajdenko
- Department of Chemistry , Moscow State University , Leninskije Gory , 199991 Moscow , Russia
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17
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Zhang J, Shukla V, Boger DL. Inverse Electron Demand Diels-Alder Reactions of Heterocyclic Azadienes, 1-Aza-1,3-Butadienes, Cyclopropenone Ketals, and Related Systems. A Retrospective. J Org Chem 2019; 84:9397-9445. [PMID: 31062977 DOI: 10.1021/acs.joc.9b00834] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A summary of the investigation and applications of the inverse electron demand Diels-Alder reaction is provided that have been conducted in our laboratory over a period that now spans more than 35 years. The work, which continues to provide solutions to complex synthetic challenges, is presented in the context of more than 70 natural product total syntheses in which the reactions served as a key strategic step in the approach. The studies include the development and use of the cycloaddition reactions of heterocyclic azadienes (1,2,4,5-tetrazines; 1,2,4-, 1,3,5-, and 1,2,3-triazines; 1,2-diazines; and 1,3,4-oxadiazoles), 1-aza-1,3-butadienes, α-pyrones, and cyclopropenone ketals. Their applications illustrate the power of the methodology, often provided concise and nonobvious total syntheses of the targeted natural products, typically were extended to the synthesis of analogues that contain deep-seated structural changes in more comprehensive studies to explore or optimize their biological properties, and highlight a wealth of opportunities not yet tapped.
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Affiliation(s)
- Jiajun Zhang
- Department of Chemistry and The Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Vyom Shukla
- Department of Chemistry and The Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Dale L Boger
- Department of Chemistry and The Skaggs Institute for Chemical Biology , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
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18
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Chen S, Ravichandiran P, El-Harairy A, Queneau Y, Li M, Gu Y. 4-Aminoindoles as 1,4-bisnucleophiles for diversity-oriented synthesis of tricyclic indoles bearing 3,4-fused seven-membered rings. Org Biomol Chem 2019; 17:5982-5989. [DOI: 10.1039/c9ob01045a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A straightforward access to tricyclic indoles bearing 3,4-fused seven-membered rings was established by using 4-aminoindoles as 1,4-bisnucleophiles in three-component reactions.
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Affiliation(s)
- Shaomin Chen
- Key Laboratory for Large-Format Battery Materials and System
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Huazhong University of Science and Technology
- Wuhan
| | - Palanisamy Ravichandiran
- Key Laboratory for Large-Format Battery Materials and System
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Huazhong University of Science and Technology
- Wuhan
| | - Ahmed El-Harairy
- Key Laboratory for Large-Format Battery Materials and System
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Huazhong University of Science and Technology
- Wuhan
| | - Yves Queneau
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- Univ Lyon
- CNRS
- Université Lyon 1
- INSA Lyon
| | - Minghao Li
- Key Laboratory for Large-Format Battery Materials and System
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Huazhong University of Science and Technology
- Wuhan
| | - Yanlong Gu
- Key Laboratory for Large-Format Battery Materials and System
- Ministry of Education
- School of Chemistry and Chemical Engineering
- Huazhong University of Science and Technology
- Wuhan
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19
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Affiliation(s)
- Marcin A. Majewski
- Wydział Chemii; Uniwersytet Wrocławski; ul. F. Joliot-Curie 14 50-383 Wrocław Polen
| | - Marcin Stępień
- Wydział Chemii; Uniwersytet Wrocławski; ul. F. Joliot-Curie 14 50-383 Wrocław Polen
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20
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Majewski MA, Stępień M. Bowls, Hoops, and Saddles: Synthetic Approaches to Curved Aromatic Molecules. Angew Chem Int Ed Engl 2018; 58:86-116. [DOI: 10.1002/anie.201807004] [Citation(s) in RCA: 236] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Marcin A. Majewski
- Wydział Chemii; Uniwersytet Wrocławski; ul. F. Joliot-Curie 14 50-383 Wrocław Poland
| | - Marcin Stępień
- Wydział Chemii; Uniwersytet Wrocławski; ul. F. Joliot-Curie 14 50-383 Wrocław Poland
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21
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Affiliation(s)
- Tetsuhiro Nemoto
- Graduate School of Pharmaceutical Sciences; Chiba University; I1-8-1, Inohana, Chuo-ku Chiba 260-8675 Japan
- Molecular Chirality Research Center; Chiba University; 1-33, Yayoi-cho, Inage-ku Chiba 263-8522, Japan
| | - Shingo Harada
- Graduate School of Pharmaceutical Sciences; Chiba University; I1-8-1, Inohana, Chuo-ku Chiba 260-8675 Japan
| | - Masaya Nakajima
- Graduate School of Pharmaceutical Sciences; Chiba University; I1-8-1, Inohana, Chuo-ku Chiba 260-8675 Japan
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22
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Kaldas SJ, Yudin AK. Achieving Skeletal Diversity in Peptide Macrocycles through The Use of Heterocyclic Grafts. Chemistry 2018; 24:7074-7082. [DOI: 10.1002/chem.201705418] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Sherif J. Kaldas
- Davenport Research Laboratories, Department of Chemistry; University of Toronto; 80 St. George St. Toronto ON M5S 3H6 Canada
| | - Andrei K. Yudin
- Davenport Research Laboratories, Department of Chemistry; University of Toronto; 80 St. George St. Toronto ON M5S 3H6 Canada
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23
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Abstract
A Perspective of work in our laboratory on the examination of biologically active compounds, especially natural products, is presented. In the context of individual programs and along with a summary of our work, selected cases are presented that illustrate the impact single atom changes can have on the biological properties of the compounds. The examples were chosen to highlight single heavy atom changes that improve activity, rather than those that involve informative alterations that reduce or abolish activity. The examples were also chosen to illustrate that the impact of such single-atom changes can originate from steric, electronic, conformational, or H-bonding effects, from changes in functional reactivity, from fundamental intermolecular interactions with a biological target, from introduction of a new or altered functionalization site, or from features as simple as improvements in stability or physical properties. Nearly all the examples highlighted represent not only unusual instances of productive deep-seated natural product modifications and were introduced through total synthesis but are also remarkable in that they are derived from only a single heavy atom change in the structure.
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Affiliation(s)
- Dale L. Boger
- Department of Chemistry and
The Skaggs Research Institute, The Scripps
Research Institute, 10550
North Torrey Pines Road, La Jolla, California 92037, United States
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24
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25
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Abstract
A review of efforts that have provided total syntheses of vancomycin and related glycopeptide antibiotics, their agylcons, and key analogues is provided. It is a tribute to developments in organic chemistry and the field of organic synthesis that not only can molecules of this complexity be prepared today by total synthesis but such efforts can be extended to the preparation of previously inaccessible key analogues that contain deep-seated structural changes. With the increasing prevalence of acquired bacterial resistance to existing classes of antibiotics and with the emergence of vancomycin-resistant pathogens (VRSA and VRE), the studies pave the way for the examination of synthetic analogues rationally designed to not only overcome vancomycin resistance but provide the foundation for the development of even more powerful and durable antibiotics.
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Affiliation(s)
- Akinori Okano
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Nicholas A Isley
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L Boger
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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26
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Mollo A, von Krusenstiern AN, Bulos JA, Ulrich V, Åkerfeldt KS, Cryle MJ, Charkoudian LK. P450 monooxygenase ComJ catalyses side chain phenolic cross-coupling during complestatin biosynthesis. RSC Adv 2017. [DOI: 10.1039/c7ra06518c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
P450 monooxygenase enzyme ComJ catalyzed biaryl ether bond formation with high efficiency and low stereoselectivity on selected complestatin-like peptide substrates.
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Affiliation(s)
- Aurelio Mollo
- Department of Chemistry
- Haverford College
- Haverford
- USA
| | | | | | - Veronika Ulrich
- Department of Biomolecular Mechanisms
- Max Planck Institute for Medical Research
- 69121 Heidelberg
- Germany
| | | | - Max J. Cryle
- Department of Biomolecular Mechanisms
- Max Planck Institute for Medical Research
- 69121 Heidelberg
- Germany
- EMBL Australia
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27
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Park J, Kim DH, Das T, Cho CG. Intramolecular Fischer Indole Synthesis for the Direct Synthesis of 3,4-Fused Tricyclic Indole and Application to the Total Synthesis of (−)-Aurantioclavine. Org Lett 2016; 18:5098-5101. [DOI: 10.1021/acs.orglett.6b02541] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jun Park
- Center
for New Directions
in Organic Synthesis, Department of Chemistry, Hanyang University, 222 Wangshimni-ro, Seongdong-gu, Seoul 04763, Korea
| | - Dong-Hyun Kim
- Center
for New Directions
in Organic Synthesis, Department of Chemistry, Hanyang University, 222 Wangshimni-ro, Seongdong-gu, Seoul 04763, Korea
| | - Tapas Das
- Center
for New Directions
in Organic Synthesis, Department of Chemistry, Hanyang University, 222 Wangshimni-ro, Seongdong-gu, Seoul 04763, Korea
| | - Cheon-Gyu Cho
- Center
for New Directions
in Organic Synthesis, Department of Chemistry, Hanyang University, 222 Wangshimni-ro, Seongdong-gu, Seoul 04763, Korea
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28
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Abstract
A mild and general protocol for the Pd(0)-catalyzed heteroannulation of o-bromoanilines and alkynes is described. Application of a Pd(0)/P((t)Bu)3 catalyst system enables the efficient coupling of o-bromoanilines at 60 °C, mitigating deleterious side reactions and enabling access to a broad range of useful unnatural tryptophans. The utility of this new protocol is demonstrated in the highly convergent total synthesis of the bisindole natural product (-)-aspergilazine A.
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Affiliation(s)
- Kangway V Chuang
- The Warren and Katharine Schlinger Laboratory of Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena, California 91125, United States
| | - Madeleine E Kieffer
- The Warren and Katharine Schlinger Laboratory of Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena, California 91125, United States
| | - Sarah E Reisman
- The Warren and Katharine Schlinger Laboratory of Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena, California 91125, United States
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29
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Glunz PW, Mueller L, Cheney DL, Ladziata V, Zou Y, Wurtz NR, Wei A, Wong PC, Wexler RR, Priestley ES. Atropisomer Control in Macrocyclic Factor VIIa Inhibitors. J Med Chem 2016; 59:4007-18. [DOI: 10.1021/acs.jmedchem.6b00244] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Peter W. Glunz
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Luciano Mueller
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Daniel L. Cheney
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Vladimir Ladziata
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Yan Zou
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Nicholas R. Wurtz
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Anzhi Wei
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Pancras C. Wong
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - Ruth R. Wexler
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
| | - E. Scott Priestley
- Bristol-Myers Squibb Research & Development, 311 Pennington-Rocky Hill Road, Pennington, New Jersey 08534, United States
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30
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Lee K, Poudel YB, Glinkerman CM, Boger DL. Total synthesis of dihydrolysergic acid and dihydrolysergol: development of a divergent synthetic strategy applicable to rapid assembly of D-ring analogs. Tetrahedron 2015; 71:5897-5905. [PMID: 26273113 PMCID: PMC4528678 DOI: 10.1016/j.tet.2015.05.093] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The total syntheses of dihydrolysergic acid and dihydrolysergol are detailed based on a Pd(0)-catalyzed intramolecular Larock indole cyclization for the preparation of the embedded tricyclic indole (ABC ring system) and a subsequent powerful inverse electron demand Diels-Alder reaction of 5-carbomethoxy-1,2,3-triazine with a ketone-derived enamine for the introduction of a functionalized pyridine, serving as the precursor for a remarkably diastereoselective reduction to the N-methylpiperidine D-ring. By design, the use of the same ketone-derived enamine and a set of related complementary heterocyclic azadiene [4 + 2] cycloaddition reactions permitted the late stage divergent preparation of a series of alternative heterocyclic derivatives not readily accessible by more conventional approaches.
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Affiliation(s)
- Kiyoun Lee
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Yam B. Poudel
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Christopher M. Glinkerman
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L. Boger
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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31
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Okano A, Nakayama A, Wu K, Lindsey EA, Schammel AW, Feng Y, Collins KC, Boger DL. Total syntheses and initial evaluation of [Ψ[C(═S)NH]Tpg⁴]vancomycin, [Ψ[C(═NH)NH]Tpg⁴]vancomycin, [Ψ[CH₂NH]Tpg⁴]vancomycin, and their (4-chlorobiphenyl)methyl derivatives: synergistic binding pocket and peripheral modifications for the glycopeptide antibiotics. J Am Chem Soc 2015; 137:3693-704. [PMID: 25750995 PMCID: PMC4376669 DOI: 10.1021/jacs.5b01008] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Full details of studies are disclosed on the total syntheses of binding pocket analogues of vancomycin bearing the peripheral L-vancosaminyl-1,2-D-glucosyl disaccharide that contain changes to a key single atom in the residue-4 amide (residue-4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late-stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral chlorobiphenyl functionalization of all of the binding-pocket-modified vancomycin analogues designed for dual D-Ala-D-Ala/D-Ala-D-Lac binding. Their collective assessment indicates that combined binding pocket and chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, and VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06-0.005 and 0.5-0.06 μg/mL for the amidine and methylene analogues, respectively) and likely benefit from two independent and synergistic mechanisms of action, only one of which is dependent on D-Ala-D-Ala/D-Ala-D-Lac binding. Such analogues are likely to display especially durable antibiotic activity that is not prone to rapidly acquired clinical resistance.
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Affiliation(s)
- Akinori Okano
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Atsushi Nakayama
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Kejia Wu
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Erick A. Lindsey
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Alex W. Schammel
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Yiqing Feng
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Karen C. Collins
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L. Boger
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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33
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Gao Y, Shan D, Jia Y. Intramolecular Larock indole synthesis for the preparation of tricyclic indoles and its application in the synthesis of tetrahydropyrroloquinoline and fargesine. Tetrahedron 2014; 70:5136-41. [DOI: 10.1016/j.tet.2014.05.108] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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34
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Nakayama A, Okano A, Feng Y, Collins J, Collins KC, Walsh CT, Boger DL. Enzymatic glycosylation of vancomycin aglycon: completion of a total synthesis of vancomycin and N- and C-terminus substituent effects of the aglycon substrate. Org Lett 2014; 16:3572-5. [PMID: 24954524 PMCID: PMC4084835 DOI: 10.1021/ol501568t] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Indexed: 02/04/2023]
Abstract
Studies on the further development of the sequential glycosylations of the vancomycin aglycon catalyzed by the glycosyltransferases GtfE and GtfD and the observation of unusual, perhaps unexpected, aglycon substrate substituent effects on the rate and efficiency of the initial glycosylation reaction are reported.
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Affiliation(s)
- Atsushi Nakayama
- Department
of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Akinori Okano
- Department
of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Yiqing Feng
- Department
of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - James
C. Collins
- Department
of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Karen C. Collins
- Department
of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Christopher T. Walsh
- Department
of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Dale L. Boger
- Department
of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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35
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Park J, Kim SY, Kim JE, Cho CG. Intramolecular Fischer Indole Synthesis in Combination with Alkyne Hydroarylation: Synthesis of Tetracyclic Chromeno-indoles. Org Lett 2013; 16:178-81. [DOI: 10.1021/ol4031638] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jun Park
- Department of Chemistry, Hanyang University, Seoul 131-791, Korea
| | - Sun-Young Kim
- Department of Chemistry, Hanyang University, Seoul 131-791, Korea
| | - Ji-Eun Kim
- Department of Chemistry, Hanyang University, Seoul 131-791, Korea
| | - Cheon-Gyu Cho
- Department of Chemistry, Hanyang University, Seoul 131-791, Korea
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36
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Pinchman JR, Boger DL. Investigation into the functional impact of the vancomycin C-ring aryl chloride. Bioorg Med Chem Lett 2013; 23:4817-9. [PMID: 23880541 DOI: 10.1016/j.bmcl.2013.06.080] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 06/27/2013] [Indexed: 11/21/2022]
Abstract
A vancomycin aglycon analogue that possesses a reduced C-ring and an intact E-ring chloride was prepared and its antimicrobial activity towards Staphylococcus aureus and binding affinity to model cell wall ligands were established. Comparison of the derivative with a series of vancomycin aglycon analogues that possess and lack the chloro substituents on the aryl C- and E-rings defines the impact and further refines the role the C-ring chloride plays in promoting both target binding affinity and binding selectivity for d-Ala-d-Ala and its impact on antimicrobial activity.
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37
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Wang C, Sperry J. Total syntheses of the dipyrrolobenzoquinone (+)-terreusinone enabled by an evaluation of 4-methylpent-1-yn-3-ols in the Larock indole synthesis. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.04.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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38
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Pinchman JR, Boger DL. Probing the role of the vancomycin e-ring aryl chloride: selective divergent synthesis and evaluation of alternatively substituted E-ring analogues. J Med Chem 2013; 56:4116-24. [PMID: 23617725 DOI: 10.1021/jm4004494] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The selective functionalization of vancomycin aglycon derivatives through conversion of the E-ring aryl chloride to a reactive boronic acid and its use in the synthesis of a systematic series of vancomycin E-ring analogues are described. The series was used to examine the E-ring chloride impact in binding d-Ala-d-Ala and on antimicrobial activity. In contrast to the reduced activity of the unsubstituted E-ring derivatives, hydrophobic and relatively nonpolar substituents approach or match the chloro-substituted vancomycin and were insensitive to the electronic character of the substituent (e.g., Cl vs CN/OMe), whereas highly polar substituents fail to provide the enhancements. Moreover, the active permethylated vancomycin aglycon derivatives exhibit VanB VRE antimicrobial activity at levels that approach (typically within 2-fold) their activity against sensitive bacteria. The robust borylation reaction also enabled the functionalization of a minimally protected vancomycin aglycon (N-Boc-vancomycin aglycon) and provides a direct method for the preparation of previously inaccessible analogues.
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Affiliation(s)
- Joseph R Pinchman
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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Shan D, Gao Y, Jia Y. Intramolecular Larock Indole Synthesis: Preparation of 3,4-Fused Tricyclic Indoles and Total Synthesis of Fargesine. Angew Chem Int Ed Engl 2013; 52:4902-5. [DOI: 10.1002/anie.201300571] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Indexed: 11/10/2022]
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Shan D, Gao Y, Jia Y. Intramolecular Larock Indole Synthesis: Preparation of 3,4-Fused Tricyclic Indoles and Total Synthesis of Fargesine. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201300571] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Abstract
Herein we report a systematic study of the Larock indole annulation designed to explore the scope and define the generality of its use in macrocyclization reactions, its use in directly accessing the chloropeptin I versus II DEF ring system as well as key unnatural isomers, its utility for both peptide-derived and more conventional carbon-chain based macrocycles, and its extension to intramolecular cyclizations with formation of common ring sizes. The studies define a powerful method complementary to the Stille or Suzuki cross-coupling reactions for the synthesis of cyclic or macrocyclic ring systems containing an embedded indole, tolerating numerous functional groups and incorporating various (up to 28-membered) ring sizes. As a result of the efforts to expand the usefulness and scope of the reaction, we also disclose a catalytic variant of the reaction, along with a powerful Pd(2)(dba)(3)-derived catalyst system, and an examination of the factors impacting reactivity and catalysis.
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Affiliation(s)
- Steven P. Breazzano
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Yam B. Poudel
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Dale L. Boger
- Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
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Iafe RG, Kuo JL, Hochstatter DG, Saga T, Turner JW, Merlic CA. Increasing the efficiency of the transannular Diels-Alder strategy via palladium(II)-catalyzed macrocyclizations. Org Lett 2013; 15:582-5. [PMID: 23343225 DOI: 10.1021/ol303394t] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Palladium(II)-catalyzed macrocyclizations of bis(vinylboronate ester) compounds are demonstrated to provide a strategically efficient approach to transannular Diels-Alder reaction substrates. In several systems reported, the macrocycle is preorganized such that cycloaddition at room temperature occurs concomitantly with cyclization. Numerous advantages over palladium(0)-catalyzed cross-coupling approaches are demonstrated.
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Affiliation(s)
- Robert G Iafe
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA
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He P, Du Y, Liu G, Cao C, Shi Y, Zhang J, Pang G. The regioselective Larock indole synthesis catalyzed by NHC–palladium complexes. RSC Adv 2013. [DOI: 10.1039/c3ra42788a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Li BL, Xu DQ, Zhong AG. Novel SO3H-functionalized ionic liquids catalyzed a simple, green and efficient procedure for Fischer indole synthesis in water under microwave irradiation. J Fluor Chem 2012. [DOI: 10.1016/j.jfluchem.2012.09.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
The glycopeptide antibiotics are the most important class of drugs used in the treatment of resistant bacterial infections including those caused by methicillin-resistant Staphylococcus aureus (MRSA). After more than 50 years of clinical use, the emergence of glycopeptide-resistant Gram-positive pathogens such as vancomycin-resistant enterococci (VRE) and vancomycin-resistant Staphylococcus aureus (VRSA) presents a serious global challenge to public health at a time few new antibiotics are being developed. This has led to renewed interest in the search for additional effective treatments including the development of new derivatives of the glycopeptide antibiotics. General approaches have been explored for modifying glycopeptide antibiotics, typically through the derivatization of the natural products themselves or more recently through chemical total synthesis. In this Perspective, we consider recent efforts to redesign glycopeptide antibiotics for the treatment of resistant microbial infections, including VRE and VRSA, and examine their future potential for providing an even more powerful class of antibiotics that are even less prone to bacterial resistance.
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Affiliation(s)
- Robert C. James
- Department of Chemistry and The Skaggs
Institute for
Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United
States
| | - Joshua G. Pierce
- Department of Chemistry and The Skaggs
Institute for
Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United
States
| | - Akinori Okano
- Department of Chemistry and The Skaggs
Institute for
Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United
States
| | - Jian Xie
- Department of Chemistry and The Skaggs
Institute for
Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United
States
| | - Dale L. Boger
- Department of Chemistry and The Skaggs
Institute for
Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United
States
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Okano A, James RC, Pierce JG, Xie J, Boger DL. Silver(I)-promoted conversion of thioamides to amidines: divergent synthesis of a key series of vancomycin aglycon residue 4 amidines that clarify binding behavior to model ligands. J Am Chem Soc 2012; 134:8790-3. [PMID: 22568755 DOI: 10.1021/ja302808p] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Development of a general Ag(I)-promoted reaction for the conversion of thioamides to amidines is disclosed. This reaction was employed to prepare a key series of vancomycin aglycon residue 4 substituted amidines that were used to clarify their interaction with model ligands of peptidoglycan precursors and explore their resulting impact on antimicrobial properties.
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Affiliation(s)
- Akinori Okano
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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Heravi MM, Hashemi E. Recent advances in application of intramolecular Suzuki cross-coupling in cyclization and heterocyclization. Monatsh Chem 2012; 143:861-80. [DOI: 10.1007/s00706-012-0746-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Martí-Centelles V, Burguete MI, Luis SV. Template Effects in SN2 Displacements for the Preparation of Pseudopeptidic Macrocycles. Chemistry 2012; 18:2409-22. [DOI: 10.1002/chem.201101416] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 09/20/2011] [Indexed: 11/07/2022]
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Xie J, Okano A, Pierce JG, James RC, Stamm S, Crane CM, Boger DL. Total synthesis of [Ψ[C(═S)NH]Tpg4]vancomycin aglycon, [Ψ[C(═NH)NH]Tpg4]vancomycin aglycon, and related key compounds: reengineering vancomycin for dual D-Ala-D-Ala and D-Ala-D-Lac binding. J Am Chem Soc 2012; 134:1284-97. [PMID: 22188323 PMCID: PMC3262083 DOI: 10.1021/ja209937s] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The total synthesis of [Ψ[C(═S)NH]Tpg(4)]vancomycin aglycon (8) and its unique AgOAc-promoted single-step conversion to [Ψ[C(═NH)NH]Tpg(4)]vancomycin aglycon (7), conducted on a fully deprotected substrate, are disclosed. The synthetic approach not only permits access to 7, but it also allows late-stage access to related residue 4 derivatives, alternative access to [Ψ[CH(2)NH]Tpg(4)]vancomycin aglycon (6) from a common late-stage intermediate, and provides authentic residue 4 thioamide and amidine derivatives of the vancomycin aglycon that will facilitate ongoing efforts on their semisynthetic preparation. In addition to early stage residue 4 thioamide introduction, allowing differentiation of one of seven amide bonds central to the vancomycin core structure, the approach relied on two aromatic nucleophilic substitution reactions for formation of the 16-membered diaryl ethers in the CD/DE ring systems, an effective macrolactamization for closure of the 12-membered biaryl AB ring system, and the defined order of CD, AB, and DE ring closures. This order of ring closures follows their increasing ease of thermal atropisomer equilibration, permitting the recycling of any newly generated unnatural atropisomer under progressively milder thermal conditions where the atropoisomer stereochemistry already set is not impacted. Full details of the evaluation of 7 and 8 along with several related key synthetic compounds containing the core residue 4 amidine and thioamide modifications are reported. The binding affinity of compounds containing the residue 4 amidine with the model D-Ala-D-Ala ligand 2 was found to be only 2-3 times less than the vancomycin aglycon (5), and this binding affinity is maintained with the model d-Ala-d-Lac ligand 4, representing a nearly 600-fold increase in affinity relative to the vancomycin aglycon. Importantly, the amidines display effective dual, balanced binding affinity for both ligands (K(a)2/4 = 0.9-1.05), and they exhibit potent antimicrobial activity against VanA resistant bacteria ( E. faecalis , VanA VRE) at a level accurately reflecting these binding characteristics (MIC = 0.3-0.6 μg/mL), charting a rational approach forward in the development of antibiotics for the treatment of vancomycin-resistant bacterial infections. In sharp contrast, 8 and related residue 4 thioamides failed to bind either 2 or 4 to any appreciable extent, do not exhibit antimicrobial activity, and serve to further underscore the remarkable behavior of the residue 4 amidines.
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Affiliation(s)
- Jian Xie
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Akinori Okano
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Joshua G. Pierce
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Robert C. James
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Simon Stamm
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Christine M. Crane
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
| | - Dale L. Boger
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037
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Affiliation(s)
- Katsuaki Ueda
- Department of Chemistry, Graduate School of Science, Tohoku University
| | - Itaru Sato
- Research and Analytical Center for Giant Molecules, Graduate School of Science, Tohoku University
| | - Masahiro Hirama
- Department of Chemistry, Graduate School of Science, Tohoku University
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