1
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Gangnale LD, Rao Boddala CS, Reddy DS. Synthesis of Stereochemical Library of a Potent Antimalarial Monocerin Derivative and Its Stereochemical Revision. Org Lett 2024; 26:7186-7190. [PMID: 39151142 DOI: 10.1021/acs.orglett.4c02619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2024]
Abstract
This study presents a total synthesis and revision of the stereochemical configuration of a potent antimalarial lead compound 2 possessing a benzo-pyranone framework, which was derived from the (+)-monocerin natural product of marine fungi, Exserohilum sp. Chiral hypervalent iodine(III)-catalyzed oxylactonization and late-stage O-methylation were highlights of the synthesis, which enabled access to the library of all possible eight stereoisomers of 2 for further understanding of stereochemical structure activity relationships (S-SARs).
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Affiliation(s)
- Laxmikant D Gangnale
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | | | - D Srinivasa Reddy
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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2
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Bulcock BW, Chen R, Lacey E, Chooi YH, Flematti GR. Ether-Diol Ambiguity: An Inconspicuous Issue in the Structure Elucidation of Oxygenated Natural Products. JOURNAL OF NATURAL PRODUCTS 2024; 87:2101-2109. [PMID: 39129216 DOI: 10.1021/acs.jnatprod.4c00675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Tertiary and allylic hydroxyl groups readily eliminate water during positive ion mode mass spectrometry and may show similar NMR spectra to their corresponding ethers. In a routine structure elucidation workflow, these factors can cause researchers to incorrectly assign diol moieties as ethers or vice versa, leading to inaccurate chemical structures. After facing this problem during our work on oxygenated sesquiterpenoids from a Fusarium sp. fungal strain, we became aware of this challenging issue. We examined the literature for oxygenated natural products bearing these functional groups, and with the aid of density functional calculations of NMR chemical shifts, we now report the structures of 15 natural products that should be revised. We further establish that derivatizing sub-micromolar amounts of alcohols to their sulfates can be used to distinguish these from their corresponding ethers using liquid chromatography negative ion mode mass spectrometry. Finally, we isolated lignoren/cyclonerodiol from the Fusarium sp. culture extract and supported its revised identity as cyclonerodiol using this sulfation approach. Our results suggest that ether-diol ambiguity could be a prevalent issue affecting the structure elucidation of oxygenated natural products and highlight the importance of using complementary techniques, such as sulfation with LC-(-)-ESI-MS or density functional calculations of NMR chemical shifts.
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Affiliation(s)
- Brodie W Bulcock
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | - Rachel Chen
- Microbial Screening Technologies Pty. Ltd., Smithfield, NSW 2164, Australia
| | - Ernest Lacey
- Microbial Screening Technologies Pty. Ltd., Smithfield, NSW 2164, Australia
| | - Yit-Heng Chooi
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | - Gavin R Flematti
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
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3
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Niu Z, Chen CY, Zhou Y, Liu GK, Zhang BY, Oppong MB, Zhang DQ, Yao T, Qiu F. Characterization of Sesquiterpene Dimers from the Flowers of Inula japonica and the Structural Revisions of Related Compounds. JOURNAL OF NATURAL PRODUCTS 2024; 87:1754-1762. [PMID: 38982404 DOI: 10.1021/acs.jnatprod.4c00269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
Sesquiterpene dimers are mainly found in the Asteraceae family. However, conflicting reports on the structures of these compounds can be found in the literature. Herein, we describe ten sesquiterpene dimers isolated from the flowers of Inula japonica, including configurational revisions of japonicone H (1-1), japonicone D (2-1), inulanolide A (4-1), japonicone X (5-1), and inulanolide F (5-2) to compounds 1, 2, 4, and 5, respectively. Five new related metabolites (3 and 6-9) are also described. Application of GIAO NMR/DP4+ analyses and ECD/OR calculations enabled us to revise the absolute configurations of an additional 13 sesquiterpene dimers isolated from plants of the genus Inula. Compounds 1, 2, 4, and 6 exhibited inhibition of nitric oxide production in lipopolysaccharide activated RAW264.7 macrophages with IC50 values of 4.07-10.00 μM.
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Affiliation(s)
- Zheng Niu
- Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine, School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Chun-Yan Chen
- National Key Laboratory of Chinese Medicine Modernization, State Key Laboratory of Component-Based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Yan Zhou
- Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine, School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Guan-Ke Liu
- Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine, School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Bing-Yang Zhang
- Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine, School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Mahmood Brobbey Oppong
- Department of Pharmaceutical Chemistry, School of Pharmacy, College of Health Sciences, University of Ghana, MR36+H7 Accra, Ghana
| | - De-Qin Zhang
- National Key Laboratory of Chinese Medicine Modernization, State Key Laboratory of Component-Based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Tie Yao
- National Key Laboratory of Chinese Medicine Modernization, State Key Laboratory of Component-Based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
| | - Feng Qiu
- Tianjin Key Laboratory of Therapeutic Substance of Traditional Chinese Medicine, School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
- National Key Laboratory of Chinese Medicine Modernization, State Key Laboratory of Component-Based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, P.R. China
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4
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Tomaník L, Pugini M, Mudryk K, Thürmer S, Stemer D, Credidio B, Trinter F, Winter B, Slavíček P. Liquid-jet photoemission spectroscopy as a structural tool: site-specific acid-base chemistry of vitamin C. Phys Chem Chem Phys 2024; 26:19673-19684. [PMID: 38963770 PMCID: PMC11267885 DOI: 10.1039/d4cp01521e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2024] [Accepted: 06/12/2024] [Indexed: 07/06/2024]
Abstract
Liquid-jet photoemission spectroscopy (LJ-PES) directly probes the electronic structure of solutes and solvents. It also emerges as a novel tool to explore chemical structure in aqueous solutions, yet the scope of the approach has to be examined. Here, we present a pH-dependent liquid-jet photoelectron spectroscopic investigation of ascorbic acid (vitamin C). We combine core-level photoelectron spectroscopy and ab initio calculations, allowing us to site-specifically explore the acid-base chemistry of the biomolecule. For the first time, we demonstrate the capability of the method to simultaneously assign two deprotonation sites within the molecule. We show that a large change in chemical shift appears even for atoms distant several bonds from the chemically modified group. Furthermore, we present a highly efficient and accurate computational protocol based on a single structure using the maximum-overlap method for modeling core-level photoelectron spectra in aqueous environments. This work poses a broader question: to what extent can LJ-PES complement established structural techniques such as nuclear magnetic resonance? Answering this question is highly relevant in view of the large number of incorrect molecular structures published.
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Affiliation(s)
- Lukáš Tomaník
- Department of Physical Chemistry, University of Chemistry and Technology, Technická 5, 16628 Prague, Czech Republic.
| | - Michele Pugini
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Karen Mudryk
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Stephan Thürmer
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-Ku, 606-8502 Kyoto, Japan
| | - Dominik Stemer
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Bruno Credidio
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Florian Trinter
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Bernd Winter
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
| | - Petr Slavíček
- Department of Physical Chemistry, University of Chemistry and Technology, Technická 5, 16628 Prague, Czech Republic.
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5
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Nishidono Y, Tanaka K. Structural Revision of Tinotufolins from Tinospora crispa Leaves Guided by Empirical Rules and DFT Calculations. JOURNAL OF NATURAL PRODUCTS 2024; 87:774-782. [PMID: 38358957 DOI: 10.1021/acs.jnatprod.3c00902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Clerodane diterpenes are a class of secondary metabolites that can be classified into four types according to the configuration of the H3-19/H-10-H3-17/H3-20 fragment, i.e., trans-cis (TC), trans-trans (TT), cis-cis (CC), and cis-trans (CT). Tinotufolins A-C and E (1a-3a and 5a), isolated from the leaves of Tinospora crispa, were previously elucidated as CT-type clerodanes; however, our established 13C NMR-based empirical rules and density functional theory calculations suggested that these clerodanes belong to the CC type. Therefore, tinotufolins A-F (1-6) were reisolated from the leaves of T. crispa, along with an undescribed compound 7 and known compounds 8-11, and their structures were established by extensive spectroscopic analyses. The structures of tinotufolins A-C and E were revised to CC-type 1-3 and 5, and undescribed compound 7 was established as a CC-type clerodane. The present study demonstrates that empirical rules and calculations can efficiently identify and revise erroneous structures in clerodane diterpenes.
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Affiliation(s)
- Yuto Nishidono
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan
- Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan
| | - Ken Tanaka
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan
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6
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Choudhury R, Miriyala SRT, Resmi KR, Sridhar B, Kasa SRKM, Reddy DS. Total Synthesis and Revision of Stereochemistry of a Natural Benzo[ g]isochromene Stereodiad Isolated from Rubia philippinensis. Org Lett 2024; 26:2574-2579. [PMID: 38513268 DOI: 10.1021/acs.orglett.4c00553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
This study presents a total synthesis and revision of the stereochemical configuration of the conformationally flexible natural product benzo[g]isochromene stereodiad alongside its diastereomeric counterparts. The highlights of the synthesis are the TiCl4-mediated diastereoselective aldol reaction, Pd-catalyzed lactonization, and Schmidt glycosidation. Our efforts using total synthesis disclosed herein proved that a previously assigned structure required revision.
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Affiliation(s)
- Rahul Choudhury
- Organic Chemistry Division, Council of Scientific and Industrial Research (CSIR)-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Satya Ravi Teja Miriyala
- Department of Organic Synthesis & Process Chemistry, Council of Scientific and Industrial Research (CSIR)-Indian Institute of Chemical Technology (IICT), Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - K R Resmi
- Centre for X-ray Crystallography, Department of Analytical & Structural Chemistry, Council of Scientific and Industrial Research (CSIR)-Indian Institute of Chemical Technology (IICT), Hyderabad 500007, India
| | - Balasubramanian Sridhar
- Centre for X-ray Crystallography, Department of Analytical & Structural Chemistry, Council of Scientific and Industrial Research (CSIR)-Indian Institute of Chemical Technology (IICT), Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | | | - D Srinivasa Reddy
- Department of Organic Synthesis & Process Chemistry, Council of Scientific and Industrial Research (CSIR)-Indian Institute of Chemical Technology (IICT), Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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7
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Çiçek SS, Mangoni A, Hanschen FS, Agerbirk N, Zidorn C. Essentials in the acquisition, interpretation, and reporting of plant metabolite profiles. PHYTOCHEMISTRY 2024; 220:114004. [PMID: 38331135 DOI: 10.1016/j.phytochem.2024.114004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 02/10/2024]
Abstract
Plant metabolite profiling reveals the diversity of secondary or specialized metabolites in the plant kingdom with its hundreds of thousands of species. Specialized plant metabolites constitute a vast class of chemicals posing significant challenges in analytical chemistry. In order to be of maximum scientific relevance, reports dealing with these compounds and their source species must be transparent, make use of standards and reference materials, and be based on correctly and traceably identified plant material. Essential aspects in qualitative plant metabolite profiling include: (i) critical review of previous literature and a reasoned sampling strategy; (ii) transparent plant sampling with wild material documented by vouchers in public herbaria and, optimally, seed banks; (iii) if possible, inclusion of generally available reference plant material; (iv) transparent, documented state-of-the art chemical analysis, ideally including chemical reference standards; (v) testing for artefacts during preparative extraction and isolation, using gentle analytical methods; (vi) careful chemical data interpretation, avoiding over- and misinterpretation and taking into account phytochemical complexity when assigning identification confidence levels, and (vii) taking all previous scientific knowledge into account in reporting the scientific data. From the current stage of the phytochemical literature, selected comments and suggestions are given. In the past, proposed revisions of botanical taxonomy were sometimes based on metabolite profiles, but this approach ("chemosystematics" or "chemotaxonomy") is outdated due to the advent of DNA sequence-based phylogenies. In contrast, systematic comparisons of plant metabolite profiles in a known phylogenetic framework remain relevant. This approach, known as chemophenetics, allows characterizing species and clades based on their array of specialized metabolites, aids in deducing the evolution of biosynthetic pathways and coevolution, and can serve in identifying new sources of rare and economically interesting natural products.
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Affiliation(s)
- Serhat S Çiçek
- Department of Biotechnology, Hamburg University of Applied Sciences, Ulmenliet 20, 21033, Hamburg, Germany
| | - Alfonso Mangoni
- Dipartimento di Farmacia, Università di Napoli Federico II, Via Domenico Montesano 49, 80131, Napoli, Italy
| | - Franziska S Hanschen
- Plant Quality and Food Security, Leibniz Institute of Vegetable and Ornamental Crops (IGZ) e. V., Theodor-Echtermeyer-Weg 1, 14979, Grossbeeren, Germany
| | - Niels Agerbirk
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg, Denmark
| | - Christian Zidorn
- Pharmazeutisches Institut, Abteilung Pharmazeutische Biologie, Christian-Albrechts- Universität zu Kiel, Gutenbergstraße 76, 24118, Kiel, Germany.
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8
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Roach J, Mital R, Haffner JJ, Colwell N, Coats R, Palacios HM, Liu Z, Godinho JLP, Ness M, Peramuna T, McCall LI. Microbiome metabolite quantification methods enabling insights into human health and disease. Methods 2024; 222:81-99. [PMID: 38185226 DOI: 10.1016/j.ymeth.2023.12.007] [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: 07/07/2023] [Revised: 10/27/2023] [Accepted: 12/13/2023] [Indexed: 01/09/2024] Open
Abstract
Many of the health-associated impacts of the microbiome are mediated by its chemical activity, producing and modifying small molecules (metabolites). Thus, microbiome metabolite quantification has a central role in efforts to elucidate and measure microbiome function. In this review, we cover general considerations when designing experiments to quantify microbiome metabolites, including sample preparation, data acquisition and data processing, since these are critical to downstream data quality. We then discuss data analysis and experimental steps to demonstrate that a given metabolite feature is of microbial origin. We further discuss techniques used to quantify common microbial metabolites, including short-chain fatty acids (SCFA), secondary bile acids (BAs), tryptophan derivatives, N-acyl amides and trimethylamine N-oxide (TMAO). Lastly, we conclude with challenges and future directions for the field.
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Affiliation(s)
- Jarrod Roach
- Department of Chemistry and Biochemistry, University of Oklahoma
| | - Rohit Mital
- Department of Biology, University of Oklahoma
| | - Jacob J Haffner
- Department of Anthropology, University of Oklahoma; Laboratories of Molecular Anthropology and Microbiome Research, University of Oklahoma
| | - Nathan Colwell
- Department of Chemistry and Biochemistry, University of Oklahoma
| | - Randy Coats
- Department of Chemistry and Biochemistry, University of Oklahoma
| | - Horvey M Palacios
- Department of Anthropology, University of Oklahoma; Laboratories of Molecular Anthropology and Microbiome Research, University of Oklahoma
| | - Zongyuan Liu
- Department of Chemistry and Biochemistry, University of Oklahoma
| | | | - Monica Ness
- Department of Chemistry and Biochemistry, University of Oklahoma
| | - Thilini Peramuna
- Department of Chemistry and Biochemistry, University of Oklahoma
| | - Laura-Isobel McCall
- Department of Chemistry and Biochemistry, University of Oklahoma; Laboratories of Molecular Anthropology and Microbiome Research, University of Oklahoma; Department of Chemistry and Biochemistry, San Diego State University.
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9
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Holland DC, Carroll AR. Structure Revision of Formyl Phloroglucinol Meroterpenoids: A Unified Approach Using NMR Fingerprinting and DFT NMR and ECD Analyses. Molecules 2024; 29:594. [PMID: 38338339 PMCID: PMC10856187 DOI: 10.3390/molecules29030594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/23/2024] [Accepted: 01/24/2024] [Indexed: 02/12/2024] Open
Abstract
NMR fingerprints are valuable tools for analyzing complex natural product mixtures and identifying incorrectly assigned structures in the literature. Our diagnostic NMR fingerprints for formyl phloroglucinol meroterpenoids revealed discrepancies in the structures reported for eucalyprobusal C (1a) and eucalypcamal K (2a). NMR fingerprinting PCA analyses identified 1a as an oxepine-diformyl phloroglucinol and 2a as an oxepine 3-acyl-1-formyl phloroglucinol, contrary to their initial assignments as pyrano-diformyl and pyrano 3-acyl-1-formyl phloroglucinols, respectively. Extensive reinterpretation of their reported one- and two-dimensional NMR data, coupled with GIAO DFT-calculated 1H and 13C NMR chemical shift and DP4+ analyses, supported the unequivocal reassignment of eucalyprobusal C to 1b and eucalypcamal K to 2b. The absolute configurations of the revised oxepine-containing phloroglucinol meroterpenoids were confirmed via the reinterpretation of their reported ROESY and NOESY NMR data, along with comparative TDDFT-calculated and experimental ECD spectra.
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Affiliation(s)
- Darren C. Holland
- School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia
- Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD 4111, Australia
| | - Anthony R. Carroll
- School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia
- Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD 4111, Australia
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10
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Zhu SH, Chang YM, Su MZ, Yao LG, Li SW, Wang H, Guo YW. Nine New Antibacterial Diterpenes and Steroids from the South China Sea Soft Coral Lobophytum catalai Tixier-Durivault. Mar Drugs 2024; 22:50. [PMID: 38276652 PMCID: PMC10817416 DOI: 10.3390/md22010050] [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: 12/28/2023] [Revised: 01/11/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024] Open
Abstract
Five new cembrane-type diterpenes, lobocalines A-E (1-5), and four new steroids, lobocaloids A-D (9-12), along with six known related compounds (6-8 and 13-15) were isolated from the Yalong Bay soft coral Lobophytum catalai Tixier-Durivault. The structures of the new compounds were elucidated by extensive spectroscopic analysis, NMR calculation with DP4+ analysis, time-dependent density functional theory-electronic circular dichroism (TDDFT-ECD) calculations, X-ray diffraction analyses and comparison with the reported spectroscopic data of known compounds. Further, with the aid of X-ray diffraction analysis, the structure of lobocrasol B (15) was firmly revised as 15a. In in vitro bioassays, compound 2 showed moderate antibacterial activities against fish pathogenic bacteria Streptococcus parauberis KSP28 and Phoyobacterium damselae FP2244 with minimum inhibitory concentration (MIC) values of 8.7 and 17.3 µg/mL, respectively. All the steroids exhibited antibacterial activities against the S. parauberis KSP28 with MIC values ranging from 12.3 to 53.6 µg/mL. Compounds 2, 7 and 14 have remarkable inhibitory effects on the hemolysin production of Staphylococcus aureus, while compounds 8-12 have medium inhibitory effects on the pyocyanin production in Pseudomonas aeruginosa.
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Affiliation(s)
- Sheng-Hui Zhu
- School of Medicine, Shanghai University, Shanghai 200444, China;
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai 264117, China; (Y.-M.C.); (M.-Z.S.); (L.-G.Y.)
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals and College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yuan-Min Chang
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai 264117, China; (Y.-M.C.); (M.-Z.S.); (L.-G.Y.)
| | - Ming-Zhi Su
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai 264117, China; (Y.-M.C.); (M.-Z.S.); (L.-G.Y.)
| | - Li-Gong Yao
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai 264117, China; (Y.-M.C.); (M.-Z.S.); (L.-G.Y.)
| | - Song-Wei Li
- School of Medicine, Shanghai University, Shanghai 200444, China;
| | - Hong Wang
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals and College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yue-Wei Guo
- School of Medicine, Shanghai University, Shanghai 200444, China;
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai 264117, China; (Y.-M.C.); (M.-Z.S.); (L.-G.Y.)
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals and College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, China
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11
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Fay N, Kouklovsky C, de la Torre A. Natural Product Synthesis: The Endless Quest for Unreachable Perfection. ACS ORGANIC & INORGANIC AU 2023; 3:350-363. [PMID: 38075446 PMCID: PMC10704578 DOI: 10.1021/acsorginorgau.3c00040] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 09/24/2023] [Accepted: 09/25/2023] [Indexed: 06/13/2024]
Abstract
Total synthesis is a field in constant progress. Its practitioners aim to develop ideal synthetic strategies to build complex molecules. As such, they are both a driving force and a showcase of the progress of organic synthesis. In this Perspective, we discuss recent notable total syntheses. The syntheses selected herein are classified according to the key strategic considerations for each approach.
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Affiliation(s)
- Nicolas Fay
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Saclay, CNRS, 17 Avenue des Sciences, 91405 Orsay, France
| | - Cyrille Kouklovsky
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Saclay, CNRS, 17 Avenue des Sciences, 91405 Orsay, France
| | - Aurélien de la Torre
- Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Université Paris-Saclay, CNRS, 17 Avenue des Sciences, 91405 Orsay, France
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12
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Novitskiy IM, Elyashberg M, Bates RW, Kutateladze AG, Williams CM. Penicitone: Structural Reassignment of a Proposed Natural Product Acid Chloride. Org Lett 2023; 25:7796-7799. [PMID: 37870401 DOI: 10.1021/acs.orglett.3c02859] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
The proposed structure for the natural product penicitone, which contained a chemically improbable acid chloride functional group, was reassigned to a more probable structure using a combination of chemical knowledge, computer-assisted structure elucidation, and DFT methods.
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Affiliation(s)
- Ivan M Novitskiy
- Department of Chemistry and Biochemistry, University of Denver, Denver, Colorado 80208, United States
| | - Mikhail Elyashberg
- Advanced Chemistry Development Inc. (ACD/Laboratories), Toronto, Ontario, Canada M5C 1B5
| | - Roderick W Bates
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Andrei G Kutateladze
- Department of Chemistry and Biochemistry, University of Denver, Denver, Colorado 80208, United States
| | - Craig M Williams
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
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13
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Hong Q, Guo MM, Yang J, Wei X, Liao L, Xin XJ, Zhang D, An FL. Four previously undescribed diketopiperazines from marine fungus Aspergillus puniceus FAHY0085 and their effects on liver X receptor α. PHYTOCHEMISTRY 2023; 214:113816. [PMID: 37536654 DOI: 10.1016/j.phytochem.2023.113816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 07/29/2023] [Accepted: 08/01/2023] [Indexed: 08/05/2023]
Abstract
Four previously undescribed diketopiperazine-type alkaloids including one oxepin-containing diketopiperazine-type alkaloid, oxepinamide L (1), three 4-quinazolinone alkaloids, puniceloids E-G (10-12), together with 12 known analogues, protuboxepin D (2), oxepinamides D-G, J-K and I (3-9), puniceloids B-D (13-15) and protubonine B (16), were isolated from the culture of the marine-derived fungus Aspergillus puniceus FAHY0085. The structures of the previously undescribed compounds were comprehensively elucidated by detailed interpretation of their NMR and HRESIMS data. Their absolute configurations were unambiguously determined by ROESY experiments, Marfey's method, calculated ECD experiments and single-crystal X-ray diffraction analysis. Compounds (3-4, 6-8, 14-15) were evaluated for their cytotoxic activity against HepG2, MCF-7, SW1116 and HeLa cells and compound 6 and 14 showed moderate cytotoxic activity against HeLa cells with IC50 49.61 ± 2.91 and 28.38 ± 1.57 μM, respectively. Compounds (1-8, 11-15) were screened for their transcriptional activation of liver X receptor α and compound 11 with known compounds 13-15 showed significant transcriptional activation of liver X receptor α with EC50 values in the range 2-50 μM.
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Affiliation(s)
- Qi Hong
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Miao-Miao Guo
- Key Laboratory of Cosmetic, China National Light Industry, Beijing Technology and Business University, No. 11/33, Fucheng Road, Beijing, 100048, China
| | - Jin Yang
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Xing Wei
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Li Liao
- Key Laboratory for Polar Science, Ministry of Natural Resources, Polar Research Institute of China, Shanghai, 200136, China; School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiu-Juan Xin
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Di Zhang
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China; Jiangsu Institute of Marine Resources Development, School of Pharmacy, Jiangsu Ocean University, Lianyungang, 222005, PR China.
| | - Fa-Liang An
- State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing, School of Biotechnology, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China; Marine Biomedical Science and Technology Innovation Platform of Lin-gang Special Area, No.4, Lane 218, Haiji Sixth Road, Shanghai, 201306, China.
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14
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Dandawate M, Choudhury R, Krishna GR, Reddy DS. Total Synthesis and Absolute Configuration Determination of the α-Glycosidase Inhibitor (3 S,4 R)-6-Acetyl-3-hydroxy-2,2-dimethylchroman-4-yl ( Z)-2-Methylbut-2-enoate from Ageratina grandifolia. JOURNAL OF NATURAL PRODUCTS 2023. [PMID: 37316456 DOI: 10.1021/acs.jnatprod.3c00236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Herein, we report the first total synthesis of α-glycosidase inhibitor (3R, 4S)-6-acetyl-3-hydroxy-2,2-dimethylchroman-4-yl (Z)-2-methylbut-2-enoate as well as its enantiomer. Our synthesis confirms the chromane structure separately proposed by Navarro-Vazquez and Mata, on the basis of DFT computations. Furthermore, our synthesis allowed us to determine the absolute configuration of the natural compound as (3S, 4R) and not (3R, 4S).
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Affiliation(s)
- Monica Dandawate
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India
| | - Rahul Choudhury
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Gamidi Rama Krishna
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India
| | - D Srinivasa Reddy
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
- CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India
- CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India
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15
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Guerrero De León E, Sánchez-Martínez H, Morán-Pinzón JA, Del Olmo Fernández E, López-Pérez JL. Computational Structural Revision of Elaeophorbate and Other Triterpenoids with the Help of NAPROC-13. A New Strategy for Structural Revision of Natural Products. JOURNAL OF NATURAL PRODUCTS 2023; 86:897-908. [PMID: 36881492 DOI: 10.1021/acs.jnatprod.2c01135] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A considerable number of natural products have been published in recent years with misassigned structure, even though they had been correctly elucidated in the past. The availability of databases containing revised structures can prevent the amplification of errors in structural elucidation. NAPROC-13, a dereplication tool based on the 13C chemical shift, has been used to search for substances that, possessing the same chemical shifts, have been described with different structures. The correct structure of these different structural proposals is verified by computational chemistry. This paper reports the structural revision of nine triterpenoids following this methodology.
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Affiliation(s)
- Estela Guerrero De León
- CIPFAR, Departamento de Farmacología, Facultad de Medicina, Universidad de Panamá, Avenue Octavio Mendez Pereira, Panama City 0824, Panama
| | - Hugo Sánchez-Martínez
- CIPFAR, Departamento de Farmacología, Facultad de Medicina, Universidad de Panamá, Avenue Octavio Mendez Pereira, Panama City 0824, Panama
| | - Juan A Morán-Pinzón
- CIPFAR, Departamento de Farmacología, Facultad de Medicina, Universidad de Panamá, Avenue Octavio Mendez Pereira, Panama City 0824, Panama
| | - Esther Del Olmo Fernández
- Departamento de Ciencias Farmacéuticas, Área de Química Farmacéutica, Facultad de Farmacia, CIETUS, IBSAL, Campus Miguel de Unamuno, University of Salamanca, 37007 Salamanca, Spain
| | - José L López-Pérez
- CIPFAR, Departamento de Farmacología, Facultad de Medicina, Universidad de Panamá, Avenue Octavio Mendez Pereira, Panama City 0824, Panama
- Departamento de Ciencias Farmacéuticas, Área de Química Farmacéutica, Facultad de Farmacia, CIETUS, IBSAL, Campus Miguel de Unamuno, University of Salamanca, 37007 Salamanca, Spain
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16
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Elyashberg M, Tyagarajan S, Mandal M, Buevich AV. Enhancing Efficiency of Natural Product Structure Revision: Leveraging CASE and DFT over Total Synthesis. Molecules 2023; 28:molecules28093796. [PMID: 37175206 PMCID: PMC10180399 DOI: 10.3390/molecules28093796] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
Natural products remain one of the major sources of coveted, biologically active compounds. Each isolated compound undergoes biological testing, and its structure is usually established using a set of spectroscopic techniques (NMR, MS, UV-IR, ECD, VCD, etc.). However, the number of erroneously determined structures remains noticeable. Structure revisions are very costly, as they usually require extensive use of spectroscopic data, computational chemistry, and total synthesis. The cost is particularly high when a biologically active compound is resynthesized and the product is inactive because its structure is wrong and remains unknown. In this paper, we propose using Computer-Assisted Structure Elucidation (CASE) and Density Functional Theory (DFT) methods as tools for preventive verification of the originally proposed structure, and elucidation of the correct structure if the original structure is deemed to be incorrect. We examined twelve real cases in which structure revisions of natural products were performed using total synthesis, and we showed that in each of these cases, time-consuming total synthesis could have been avoided if CASE and DFT had been applied. In all described cases, the correct structures were established within minutes of using the originally published NMR and MS data, which were sometimes incomplete or had typos.
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Affiliation(s)
- Mikhail Elyashberg
- Advanced Chemistry Development Inc. (ACD/Labs), Toronto, ON M5C 1B5, Canada
| | | | - Mihir Mandal
- Medicinal Chemistry, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Alexei V Buevich
- Analytical Research and Development, Merck & Co., Inc., Kenilworth, NJ 07033, USA
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17
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Wu Z, Guo H, Wu Q, Jiang M, Chen J, Chen B, Li H, Liu L, Chen S. Absolute configuration of cyclopropanes and the structural revision of pyrones from Marine-derived fungus Stagonospora sp. SYSU-MS7888. Bioorg Chem 2023; 136:106542. [PMID: 37087848 DOI: 10.1016/j.bioorg.2023.106542] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 04/04/2023] [Accepted: 04/11/2023] [Indexed: 04/25/2023]
Abstract
Two new cyclopropane derivatives (1-2) and seven undescribed α-pyrone derivatives (3-9), along with one known congener (10) were obtained from the marine fungus Stagonospora sp. SYSU-MS7888, which was isolated from the South China Sea. Their planar structures were established through extensive spectroscopic analyses including 1D and 2D NMR and HR-ESIMS. The absolute configurations were identified on basis of the quantum chemical calculations of ECD and NMR, as well as the modified Mosher's method. It's particularly noteworthy that the tetrasubstituted furopyrans, chenopodolans A-F, possessing phytotoxicity and zootoxicity, were structural misassignments. The structures of chenopodolans featuring with furopyran skeleton were revised as common trisubstituted α-pyrones by computational chemistry, NMR spectroscopic method, and empirical rule. Compounds 1, 2, 7, and 9 showed significant anti-inflammatory activity with IC50 values ranging from 3.6 to 22.8 μM, which is better than the positive control indomethacin (IC50 = 26.5 ± 1.13 μM). This discovery holds potential for the development of new anti-inflammatory agents.
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Affiliation(s)
- Zhenger Wu
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519000, China
| | - Heng Guo
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519000, China
| | - Qilin Wu
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519000, China
| | - Minghua Jiang
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519000, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China
| | - Junjie Chen
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519000, China
| | - Bin Chen
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China
| | - Hanxiang Li
- Institutional Center for Shared Technologies and Facilities, South China Botanical Garden, Chinese Academy of Sciences (CAS), Guangzhou 510650, China
| | - Lan Liu
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519000, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China
| | - Senhua Chen
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519000, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China; Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education, Hainan Normal University, Haikou 571158, China.
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18
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Tian XH, Hong LL, Jiao WH, Lin HW. Natural sesquiterpene quinone/quinols: chemistry, biological activity, and synthesis. Nat Prod Rep 2023; 40:718-749. [PMID: 36636914 DOI: 10.1039/d2np00045h] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Covering: 2010 to 2021Sesquiterpene quinone/quinols (SQs) are characterized by a C15-sesquiterpenoid unit incorporating a C6-benzoquinone/quinol moiety. Numerous unprecedented carbon skeletons have been constructed with various connection patterns between the two parts. The potent anti-cancer, anti-inflammatory, anti-microbial, anti-viral, and fibrinolytic activities of SQs are associated with their diverse structures. The representative avarol has even entered the stage of clinical phase II research as an anti-HIV agent, and was developed as paramedic medicine against psoriasis. This review provides an overall summary of 558 new natural SQs discovered between 2010 and 2021, including seven groups and sixteen structure-type subgroups, which comprehensively recapitulates their chemical structures, spectral characteristics, source organisms, biological activities, synthesis, and biosynthesis, aiming to expand the application scope of this unique natural product resource.
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Affiliation(s)
- Xin-Hui Tian
- Marine Drugs Research Center, Department of Pharmacy, Ren Ji Hospital, School of Medicine, State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200127, P. R. China.
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, P. R. China.
| | - Li-Li Hong
- Marine Drugs Research Center, Department of Pharmacy, Ren Ji Hospital, School of Medicine, State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200127, P. R. China.
| | - Wei-Hua Jiao
- Marine Drugs Research Center, Department of Pharmacy, Ren Ji Hospital, School of Medicine, State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200127, P. R. China.
| | - Hou-Wen Lin
- Marine Drugs Research Center, Department of Pharmacy, Ren Ji Hospital, School of Medicine, State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai 200127, P. R. China.
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19
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Hill A, Wang F. Intramolecular O···H Hydrogen Bonding of Salicylic Acid: Further Insights from O 1s XPS and 1H NMR Spectra Using DFT Calculations. J Phys Chem A 2023; 127:2705-2716. [PMID: 36939708 DOI: 10.1021/acs.jpca.2c08981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2023]
Abstract
Intramolecular hydrogen bonding (HB) is a complex phenomenon that extends beyond a simple valence event, affecting the core electrons of a molecule. Salicylic acid (SA) and its conformers provide an excellent model compound for studying intramolecular HB as the proton donor (H) and acceptor (O) can be toggled by rotating the C-O and C-C bonds to form up to seven potential conformers through various HB. In this study, we computationally investigated intramolecular interactions in SA conformers with and without such HB, by examining their calculated O 1s core electron-binding energy (CEBE) and 1H NMR chemical shifts validated using recent measurements. The quantum mechanically stable SA conformers are fully defined by three rotatable bonds in the compound, which are abstracted as SA(η1η2η3) digital structures, where ηi = 0 if the ηi angles match the most stable SA conformer (000) and ηi = 1 otherwise. Our findings suggest that the stability is dominated by the appearance of the intergroup intramolecular HB of Hp···O (where O is in the carboxylic acid functional group and Hp is the phenolic proton in -OHp), and η3 serves as a switch of such HB. As a result, the (η1η20) SA conformers containing such Hp···O HB are more stable than other SA conformers (η1η21) without such the Hp···O HB. The present density functional theory calculations reveal that this Hp···O HB results in splitting of the O 1s CEBEs of two hydroxyl groups (-OH) by up to 1 eV and deshielding the Hp proton 1H NMR (δHp) up to 11.68 ppm for the (η1η20) conformers. Without such Hp···O HB, the O 1s XPS binding energies of two -OH groups will be closely located in the same band, and the 1H NMR chemical shift of the Hp atom will be as small as an 4.09 ppm SA conformer [SA-G(101)]. The present study indicates that the O 1s CEBE splitting between two -OH groups serves as an indicator of the presence of the Hp···O HB in SA conformers, which is also supported by the 1H NMR results.
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Affiliation(s)
- Alexander Hill
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
| | - Feng Wang
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
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20
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Chen ZH, Yu DD, Li C, Su MZ, Wu Q, Zhang ZY, Wang JR, Li J, Guo YW. Guided Isolation of An Uncommon Cembranoid Orthoester, Sarcotortin A, and Three Skeletal Diverse Terpenoids from the Hainan Soft Coral Sarcophyton tortuosum Based on Molecular Networking Strategy. Chemistry 2023; 29:e202203487. [PMID: 36562597 DOI: 10.1002/chem.202203487] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/24/2022]
Abstract
Applying the emerging molecular networking strategy, an uncommon cembranoid orthoester, sarcotortin A (1), featuring a 3/14/8/5-fused scaffold, an unusual eunicellane-type diterpenoid, sarcotorolide A (2), and two new biscembranoids, ximaolides M and N (7 and 8), along with nine known terpenoids 3-6 and 9-13 were isolated from the Hainan soft coral Sarcophyton tortuosum. The structure and absolute configuration of all new compounds were established by a combination of spectroscopic data, X-ray diffraction analysis, and/or quantum chemical computational approaches. The plausible biogenetic relationship among these skeletally different terpenoids was proposed and discussed. In in vitro bioassay, new compound 7 exhibited a remarkable inhibitory activity against protein tyrosine phosphatases 1B (PTP1B) with the IC50 value of 8.06 μM. In addition, compounds 4 and 10 displayed significant inhibitory effects on lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 macrophages cells with the IC50 values of 19.13 and 16.45 μM, respectively. Compound 9 showed interesting cytotoxicity against H1975, MDA-MB231, A549, and H1299 cancer cell lines with IC50 values of 31.59, 34.96, 43.87, and 27.93 μM, respectively.
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Affiliation(s)
- Zi-Hui Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, P.R. China.,University of Chinese Academy of Sciences, No. 19 A Yuquan Road, Beijing, 100049, P.R. China
| | - Dan-Dan Yu
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong, 264117, P.R. China
| | - Cong Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, P.R. China
| | - Ming-Zhi Su
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong, 264117, P.R. China
| | - Qihao Wu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, P.R. China
| | - Zai-Yong Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, P.R. China
| | - Jian-Rong Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, P.R. China
| | - Jia Li
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, P.R. China
| | - Yue-Wei Guo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, P.R. China.,University of Chinese Academy of Sciences, No. 19 A Yuquan Road, Beijing, 100049, P.R. China.,Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong, 264117, P.R. China
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21
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Wang F. Future of computational molecular spectroscopy-from supporting interpretation to leading the innovation. Phys Chem Chem Phys 2023; 25:7090-7105. [PMID: 36826794 DOI: 10.1039/d3cp00192j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Molecular spectroscopy measures transitions between discrete molecular energies which follow quantum mechanics. Structural information of a molecule is encoded in the spectra, which can be only decoded using quantum mechanics and therefore computational molecular spectroscopy becomes essential. In this review perspective, the role evolution of computational molecular spectroscopy has been discussed with several joint theory and experiment spectroscopic studies in the past decades, which includes rotational (microwave), vibrational and electronic spectroscopy (valence and core) of molecules. With the development in high resolution and computerized synchrotron sourced spectroscopy, spectral measurements and computational molecular spectroscopy need to be integrated for materials development. Contemporary computational molecular spectroscopy is, therefore, more than merely supporting interpretation but leading the innovation. Future development of molecular spectroscopy lies to identify the niche to integrate experimental and computational molecular spectroscopy. It also requires to engineer molecular spectroscopic databases that function according to the universal approaches of computing, such as those in a Turing machine, to be realized in a chemical and/or spectroscopic programable manner (digital twinning research) in the future.
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Affiliation(s)
- Feng Wang
- Department of Chemistry and Biotechnology, School of Science, Computing and Engineering Technologies, Swinburne University of Technology, Melbourne, Victoria 3122, Australia.
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22
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Kutateladze AG, Bates RW, Elyashberg M, Williams CM. Structural Reassignment of Two Polyenol Natural Products. European J Org Chem 2023. [DOI: 10.1002/ejoc.202201316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | - Roderick W. Bates
- School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University 21 Nanyang Link Singapore 637371 Singapore
| | - Mikhail Elyashberg
- Advanced Chemistry Development Inc. (ACD/Labs) Toronto ON M5 C 1B5 Canada
| | - Craig M. Williams
- School of Chemistry and Molecular Biosciences University of Queensland Brisbane 4072 Queensland Australia
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23
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Wu MJ, Yu DD, Du YQ, Zhang J, Su MZ, Jiang CS, Guo YW. Further undescribed cembranoids from South China Sea soft coral Sarcophyton ehrenbergi: Structural elucidation and biological evaluation. PHYTOCHEMISTRY 2023; 206:113549. [PMID: 36481314 DOI: 10.1016/j.phytochem.2022.113549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/25/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
A detailed chemical investigation of the South China Sea soft coral Sarcophyton ehrenbergi has yield seven undescribed cembranoids, namely isoehrenbergol D and sarcoehrenolides F-K embodying a rare α,β-unsaturated-lactone moiety at C-6 to C-19, along with two known related compounds, ehrenbergol D and sarcoehrenolide A. Their structures and absolute configurations were unambiguously established in the light of extensive spectroscopic data analysis, modified Mosher's method, X-ray diffraction analysis, and quantum chemical computation method. In a bioassay for α-glucosidase inhibition, ehrenbergol D was evaluated as α-glucosidase inhibitor with an IC50 value of 13.57 μM.
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Affiliation(s)
- Meng-Jun Wu
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals and College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310014, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, China
| | - Dan-Dan Yu
- College of Pharmacy, Guangdong Medical University, Zhanjiang, Guangdong, 524023, PR China; Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong, 264117, China
| | - Ye-Qing Du
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, China
| | - Juan Zhang
- School of Biological Science and Technology, University of Jinan, Jinan, 250022, China
| | - Ming-Zhi Su
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong, 264117, China.
| | - Cheng-Shi Jiang
- School of Biological Science and Technology, University of Jinan, Jinan, 250022, China.
| | - Yue-Wei Guo
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals and College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310014, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai, 201203, China; College of Pharmacy, Guangdong Medical University, Zhanjiang, Guangdong, 524023, PR China; Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, Shandong, 264117, China.
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24
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Computational Approaches to Enzyme Inhibition by Marine Natural Products in the Search for New Drugs. Mar Drugs 2023; 21:md21020100. [PMID: 36827141 PMCID: PMC9961086 DOI: 10.3390/md21020100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/26/2023] [Accepted: 01/28/2023] [Indexed: 02/03/2023] Open
Abstract
The exploration of biologically relevant chemical space for the discovery of small bioactive molecules present in marine organisms has led not only to important advances in certain therapeutic areas, but also to a better understanding of many life processes. The still largely untapped reservoir of countless metabolites that play biological roles in marine invertebrates and microorganisms opens new avenues and poses new challenges for research. Computational technologies provide the means to (i) organize chemical and biological information in easily searchable and hyperlinked databases and knowledgebases; (ii) carry out cheminformatic analyses on natural products; (iii) mine microbial genomes for known and cryptic biosynthetic pathways; (iv) explore global networks that connect active compounds to their targets (often including enzymes); (v) solve structures of ligands, targets, and their respective complexes using X-ray crystallography and NMR techniques, thus enabling virtual screening and structure-based drug design; and (vi) build molecular models to simulate ligand binding and understand mechanisms of action in atomic detail. Marine natural products are viewed today not only as potential drugs, but also as an invaluable source of chemical inspiration for the development of novel chemotypes to be used in chemical biology and medicinal chemistry research.
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Zachmann R, Yahata K, Holzheimer M, Jarret M, Wirtz C, Fürstner A. Total Syntheses of Nominal and Actual Prorocentin. J Am Chem Soc 2023; 145:2584-2595. [PMID: 36652728 PMCID: PMC9896551 DOI: 10.1021/jacs.2c12529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The dinoflagellate-derived polyether prorocentin is a co-metabolite of the archetypical serine/threonine phosphatase inhibitor okadaic acid. Whereas a structural relationship cannot be missed and a biosynthetic link was proposed, it is currently unknown whether there is any parallel in the bioactivity profile of these natural products. However, it was insinuated in the past that the structure assigned to prorocentin might need to be revised. Indeed, re-examination of the published spectra cast doubts as to the constitution of the fused/spirotricyclic BCD-ring system in the core. To clarify this issue, a flexible synthesis blueprint was devised that allowed us to obtain the originally proposed structure as well as the most plausible amended structure. The key to success was late-stage gold-catalyzed spirocyclization reactions that furnished the isomeric central segments with excellent selectivity. The lexicon of catalytic transformations used to make the required cyclization precursors comprised a titanium-mediated ester methylenation/metathesis cascade, a rare example of a gold-catalyzed allylic substitution, and chain extensions via organocatalytic asymmetric aldehyde propargylation. A wing sector to be attached to the isomeric cores was obtained by Krische allylation, followed by a superbly selective cobalt-catalyzed oxidative cyclization of the resulting di-unsaturated alcohol with the formation of a 2,5-trans-disubstituted tetrahydrofuran; the remaining terminal alkene was elaborated into an appropriate handle for fragment coupling by platinum-catalyzed asymmetric diboration/oxidation. The assembly of the different building blocks to the envisaged isomeric target compounds proved that the structure of prorocentin needs to be revised as disclosed herein.
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Ji J, Li H, Liu C, Chen Y, Li R, Zhang Z. Synthesis, Crystal Structure, and Activity of Cu(II) and Zn(II) Complexes of 2-Mercaptoquinoline N-Oxide. RUSS J GEN CHEM+ 2023. [DOI: 10.1134/s1070363223010243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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Liu J, Gu YC, Su MZ, Guo YW. Chemistry and bioactivity of secondary metabolites from South China Sea marine fauna and flora: recent research advances and perspective. Acta Pharmacol Sin 2022; 43:3062-3079. [PMID: 36104434 PMCID: PMC9712606 DOI: 10.1038/s41401-022-00980-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 08/09/2022] [Indexed: 11/09/2022] Open
Abstract
Marine organisms often produce a variety of metabolites with unique structures and diverse biological activities that enable them to survive and struggle in the extremely challenging environment. During the last two decades, our group devoted great effort to the discovery of pharmaceutically interesting lead compounds from South China Sea marine plants and invertebrates. We discovered numerous marine secondary metabolites spanning a wide range of structural classes, various biosynthetic origins and various aspects of biological activities. In a series of reviews, we have summarized the bioactive natural products isolated from Chinese marine flora and fauna found during 2000-2012. The present review provides an updated summary covering our latest research progress and development in the last decade (2012-2022) highlighting the discovery of over 400 novel marine secondary metabolites with promising bioactivities from South China Sea marine organisms.
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Affiliation(s)
- Jiao Liu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yu-Cheng Gu
- Syngenta, Jealott's Hill International Research Centre, Bracknell, Berkshire, RG42 6EY, UK
| | - Ming-Zhi Su
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, 264117, China.
| | - Yue-Wei Guo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, Yantai, 264117, China.
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Bu Q, Yang M, Yan XY, Yao LG, Guo YW, Liang LF. New flexible cembrane-type macrocyclic diterpenes as TNF-α inhibitors from the South China Sea soft coral Sarcophyton mililatensis. Int J Biol Macromol 2022; 222:880-886. [PMID: 36179867 DOI: 10.1016/j.ijbiomac.2022.09.210] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 09/21/2022] [Accepted: 09/23/2022] [Indexed: 11/26/2022]
Abstract
A further study on the rarely reported soft coral Sarcophyton mililatensis disclosed five new flexible cembrane-type macrocyclic diterpenes sarcomililatols C-G (1-5) and two known analogues 6 and 7. The structures and absolute configurations of natural macrocyclic compounds 1-6 were established by the extensive spectroscopic analysis, X-ray diffraction analysis, time-dependent density functional theory/electronic circular dichroism (TDDFT ECD) calculations, chemical reaction, and modified Mosher's method. In the bioassays, the macrocyclic diterpene 2 exhibited potent TNF-α inhibition (IC50 = 6.1 μmol/L), which was better than the positive control dexamethasone (IC50 = 8.7 μmol/L), and no obvious cytotoxicity against RAW264.7 cells with CC50 values over 50 μmol/L, indicating natural macrocyclic compound 2 could be served as a model compound to develop a new and prospective chemotype of an anti-inflammatory lead compound or drug candidate.
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Affiliation(s)
- Qing Bu
- College of Materials Science and Engineering, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha 410004, China
| | - Min Yang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555, Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Xian-Yun Yan
- College of Materials Science and Engineering, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha 410004, China
| | - Li-Gong Yao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555, Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China
| | - Yue-Wei Guo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555, Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, China; Shandong Laboratory of Yantai Drug Discovery, Bohai rim Advanced Research Institute for Drug Discovery, Yantai, Shandong 264117, China; Open Studio for Druggability Research of Marine Natural Products, Pilot National Laboratory for Marine Science and Technology (Qingdao), 1 Wenhai Road, Aoshanwei, Jimo, Qingdao 266237, China; Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals and College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, China.
| | - Lin-Fu Liang
- College of Materials Science and Engineering, Central South University of Forestry and Technology, 498 South Shaoshan Road, Changsha 410004, China.
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Polyoxygenated cembranoids from the South China Sea soft coral Sarcophyton boettgeri and their stereochemistry. Fitoterapia 2022; 162:105299. [PMID: 36113666 DOI: 10.1016/j.fitote.2022.105299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/23/2022]
Abstract
Four new polyoxygenated cembranoids, namely sarcoboettgerol A (1), 12-epi-humilisin D (2), sarcoboettgerol B (3), and sarcoboettgerol C (4), together with one known related analogue, humilisin D (5), were isolated and characterized from the soft coral Sarcophyton boettgeri collected off Ximao island, Hainan Province, China. The structures and absolute configurations of the new compounds were determined by extensive spectroscopic data analyses, Cu kα single crystal X-ray diffraction analysis, and TDDFT-ECD calculations. A plausible biogenetic relationship of 3 and 4 was proposed.
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Li W, Gao Q, Hu Y, Shi Y, Yan X, Ding L, He S. Dibetanide, a new benzofuran derivative with the rare conjugated triene side chain from a sponge-associated fungus Aspergillus species. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.134082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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