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Abstract
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The therapeutic properties of Curcuma (ginger
and turmeric’s family) have long been known in traditional
medicine. However, only recently have guaiane-type sesquiterpenes
extracted from Curcuma phaeocaulis been
submitted to biological testing, and their enhanced bioactivity was
highlighted. Among these compounds, phaeocaulisin A has shown remarkable
anti-inflammatory and anticancer activity, which appears to be tied
to the unique bridged acetal moiety embedded in its tetracyclic framework.
Prompted by the promising biological profile of phaeocaulisin A and
by the absence of a synthetic route for its provision, we have implemented
the first enantioselective total synthesis of phaeocaulisin A in 17
steps with 2% overall yield. Our route design builds on the identification
of an enantioenriched lactone intermediate, tailored with both a ketone
moiety and a conjugated alkene system. Taking advantage of the umpolung
carbonyl-olefin coupling reactivity enabled by the archetypal single-electron
transfer (SET) reductant samarium diiodide (SmI2), the
lactone intermediate was submitted to two sequential SmI2-mediated cyclizations to stereoselectively construct the polycyclic
core of the natural product. Crucially, by exploiting the innate inner-sphere
nature of carbonyl reduction using SmI2, we have used a
steric blocking strategy to render sites SET-unreceptive and thus
achieve chemoselective reduction in a complex substrate. Our asymmetric
route enabled elucidation of the naturally occurring isomer of phaeocaulisin
A and provides a synthetic platform to access other guaiane-type sesquiterpenes
from C. phaeocaulis—as well
as their synthetic derivatives—for medicinal chemistry and
drug design.
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Affiliation(s)
- Áron Péter
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Giacomo E M Crisenza
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - David J Procter
- Department of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
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2
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Ishihara J. Chiral Lewis Acid-template Diels-Alder Reaction and the Application of Natural Product Synthesis. J SYN ORG CHEM JPN 2020. [DOI: 10.5059/yukigoseikyokaishi.78.204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Jun Ishihara
- Graduate School of Biomedical Sciences, Nagasaki University
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3
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Qiu ZB, Ren XF, Chen XY, Chen LY, Ji J, Li Y. MgBr2OEt2-promoted direct Aldol reactions of S-aryl 2-fluoroethanethioate. J Fluor Chem 2019. [DOI: 10.1016/j.jfluchem.2019.109368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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4
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Minamino K, Murata M, Tsuchikawa H. Synthesis of 7,6-Spirocyclic Imine with Butenolide Ring Provides Evidence for the Relative Configuration of Marine Toxin 13-desMe Spirolide C. Org Lett 2019; 21:8970-8975. [DOI: 10.1021/acs.orglett.9b03373] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Kou Minamino
- Department of Chemistry, Faculty of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Michio Murata
- Department of Chemistry, Faculty of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Hiroshi Tsuchikawa
- Department of Chemistry, Faculty of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
- Research Promotion Institute, Oita University, 1-1 Idaigaoka, Hasama, Yufu, Oita 879-5593, Japan
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Freeman JL, Brimble MA, Furkert DP. Convenient access to 5-membered cyclic iminium ions: evidence for a stepwise [4 + 2] cycloaddition mechanism. Org Biomol Chem 2019; 17:2705-2714. [PMID: 30768089 DOI: 10.1039/c9ob00262f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In situ generation and reaction of novel 5-membered N-tosyl cyclic α,β-unsaturated iminium ions from readily prepared stable precursors is demonstrated. Formal iminium Diels-Alder cycloaddition proceeded in good yield via a stepwise rather than concerted cycloaddition process, confirmed through the isolation of a Mukaiyama-Michael type intermediate. Relative stereochemistry was determined upon subsequent intramolecular cyclisation under Lewis acid catalysis to afford formal endo 5,6-spirobicyclic adducts, as confirmed by crystallography. Further synthetic elaboration towards complex molecular scaffolds based on the dinoflagellate metabolite portimine, a potent apoptosis inducer, were also developed.
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Affiliation(s)
- Jared L Freeman
- School of Chemical Sciences, The University of Auckland, Symonds Street, Auckland 1010, New Zealand.
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6
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Ishihara J, Usui F, Kurose T, Baba T, Kawaguchi Y, Watanabe Y, Hatakeyama S. Synthetic Studies on Spirolides A and B: Formation of the Upper Carbon Framework Based on a Lewis Acid Template-Catalyzed Diels-Alder Reaction. Chemistry 2018; 25:1543-1552. [DOI: 10.1002/chem.201804977] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Jun Ishihara
- Graduate School of Biomedical Sciences; Nagasaki University; 1-14, Bunkyo-machi Nagasaki 852-8521 Japan
| | - Fuma Usui
- Graduate School of Biomedical Sciences; Nagasaki University; 1-14, Bunkyo-machi Nagasaki 852-8521 Japan
| | - Tomohiro Kurose
- Graduate School of Biomedical Sciences; Nagasaki University; 1-14, Bunkyo-machi Nagasaki 852-8521 Japan
| | - Tomohiro Baba
- Graduate School of Biomedical Sciences; Nagasaki University; 1-14, Bunkyo-machi Nagasaki 852-8521 Japan
| | - Yasunori Kawaguchi
- Graduate School of Biomedical Sciences; Nagasaki University; 1-14, Bunkyo-machi Nagasaki 852-8521 Japan
| | - Yuki Watanabe
- Graduate School of Biomedical Sciences; Nagasaki University; 1-14, Bunkyo-machi Nagasaki 852-8521 Japan
| | - Susumi Hatakeyama
- Medical Innovation Center; Nagasaki University; 1-14, Bunkyo-machi Nagasaki 852-8521 Japan
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7
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8
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Tsuchikawa H, Minamino K, Hayashi S, Murata M. Efficient Access to the Functionalized Bicyclic Pharmacophore of Spirolide C by Using a Selective Diels–Alder Reaction. ASIAN J ORG CHEM 2017. [DOI: 10.1002/ajoc.201700164] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Hiroshi Tsuchikawa
- Graduate School of Science Osaka University 1-1 Machikaneyama Toyonaka Osaka 560-0043 Japan
| | - Kou Minamino
- Graduate School of Science Osaka University 1-1 Machikaneyama Toyonaka Osaka 560-0043 Japan
| | - Sho Hayashi
- Graduate School of Science Osaka University 1-1 Machikaneyama Toyonaka Osaka 560-0043 Japan
| | - Michio Murata
- Graduate School of Science Osaka University 1-1 Machikaneyama Toyonaka Osaka 560-0043 Japan
- ERATO Lipid Active Structure Project Science and Technology Agency 1-1 Machikaneyama Toyonaka Osaka 560-0043 Japan
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9
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Stivala CE, Benoit E, Aráoz R, Servent D, Novikov A, Molgó J, Zakarian A. Synthesis and biology of cyclic imine toxins, an emerging class of potent, globally distributed marine toxins. Nat Prod Rep 2015; 32:411-35. [PMID: 25338021 DOI: 10.1039/c4np00089g] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
From a small group of exotic compounds isolated only two decades ago, Cyclic Imine (CI) toxins have become a major class of marine toxins with global distribution. Their distinct chemical structure, biological mechanism of action, and intricate chemistry ensures that CI toxins will continue to be the subject of fascinating fundamental studies in the broad fields of chemistry, chemical biology, and toxicology. The worldwide occurrence of potent CI toxins in marine environments, their accumulation in shellfish, and chemical stability are important considerations in assessing risk factors for human health. This review article aims to provide an account of chemistry, biology, and toxicology of CI toxins from their discovery to the present day.
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Affiliation(s)
- Craig E Stivala
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
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10
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Hog DT, Huber FME, Jiménez-Osés G, Mayer P, Houk KN, Trauner D. Evolution of a Unified Strategy for Complex Sesterterpenoids: Progress toward Astellatol and the Total Synthesis of (-)-Nitidasin. Chemistry 2015; 21:13646-65. [PMID: 26300211 PMCID: PMC4696511 DOI: 10.1002/chem.201501423] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Indexed: 12/19/2022]
Abstract
Astellatol and nitidasin belong to a subset of sesterterpenoids that share a sterically encumbered trans-hydrindane motif with an isopropyl substituent. In addition, these natural products feature intriguing polycyclic ring systems, posing significant challenges for chemical synthesis. Herein, the evolution of our stereoselective strategy for isopropyl trans-hydrindane sesterterpenoids is detailed. These endeavors included the synthesis of several building blocks, enabling studies toward all molecules of this terpenoid subclass, and of advanced intermediates of our initial route toward a biomimetic synthesis of astellatol. These findings provided the basis for a second-generation and a third-generation approach toward astellatol that eventually culminated in the enantioselective total synthesis of (-)-nitidasin. In particular, a series of substrate-controlled transformations to install the ten stereogenic centers of the target molecule was orchestrated and the carbocyclic backbone was forged in a convergent fashion. Furthermore, the progress toward the synthesis of astellatol is disclosed and insights into some observed yet unexpected diastereoselectivities by detailed quantum-mechanical calculations are provided.
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Affiliation(s)
- Daniel T Hog
- Department for Chemistry and Center of Integrated Protein Science, Ludwig-Maximilians-Universität München, Butenandstr. 5-13, 81377 München (Germany)
- Present address: Bayer Health Care, Bayer Pharma AG, BPH-GDD-CGEI-MCB-MCII, Müllerstr. 178, 13353 Berlin (Germany)
| | - Florian M E Huber
- Department for Chemistry and Center of Integrated Protein Science, Ludwig-Maximilians-Universität München, Butenandstr. 5-13, 81377 München (Germany)
| | - Gonzalo Jiménez-Osés
- Department of Chemistry and Biochemistry, University of California, 607 Charles E. Young Drive East, Los Angeles, CA 90095 (USA).
| | - Peter Mayer
- Department for Chemistry and Center of Integrated Protein Science, Ludwig-Maximilians-Universität München, Butenandstr. 5-13, 81377 München (Germany)
| | - Kendall N Houk
- Department of Chemistry and Biochemistry, University of California, 607 Charles E. Young Drive East, Los Angeles, CA 90095 (USA)
| | - Dirk Trauner
- Department for Chemistry and Center of Integrated Protein Science, Ludwig-Maximilians-Universität München, Butenandstr. 5-13, 81377 München (Germany).
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Lu P, Jackson JJ, Eickhoff JA, Zakarian A. Direct enantioselective conjugate addition of carboxylic acids with chiral lithium amides as traceless auxiliaries. J Am Chem Soc 2015; 137:656-9. [PMID: 25562717 PMCID: PMC4308744 DOI: 10.1021/ja512213c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Michael addition is a premier synthetic method for carbon-carbon and carbon-heteroatom bond formation. Using chiral dilithium amides as traceless auxiliaries, we report the direct enantioselective Michael addition of carboxylic acids. A free carboxyl group in the product provides versatility for further functionalization, and the chiral reagent can be readily recovered by extraction with aqueous acid. The method has been applied in the enantioselective total synthesis of the purported structure of pulveraven B.
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Affiliation(s)
- Ping Lu
- Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States
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12
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Herndon JW. The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2012. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2014.02.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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13
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Cornil J, Gonnard L, Guérinot A, Reymond S, Cossy J. Lewis Acid Catalyzed Synthesis of Cyclic Carbonates, Precursors of 1,2- and 1,3-Diols. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402557] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Kunitake M, Oshima T, Konoki K, Ebine M, Torikai K, Murata M, Oishi T. Synthesis and biological activity of the C'D'E'F' ring system of maitotoxin. J Org Chem 2014; 79:4948-62. [PMID: 24810995 DOI: 10.1021/jo5005235] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Stereoselective synthesis of the C'D'E'F' ring system of maitotoxin was achieved starting from the E' ring through successive formation of the D' and C' rings based on SmI2-mediated reductive cyclization. Construction of the F' ring was accomplished via Suzuki-Miyaura cross-coupling with a side chain fragment and Pd(II)-catalyzed cyclization of an allylic alcohol. The C'D'E'F' ring system inhibited maitotoxin-induced Ca(2+) influx in rat glioma C6 cells with an IC50 value of 59 μM.
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Affiliation(s)
- Masahiro Kunitake
- Department of Chemistry, Faculty and Graduate School of Sciences, Kyushu University , 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
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Grosso C, Valentão P, Ferreres F, Andrade PB. Bioactive marine drugs and marine biomaterials for brain diseases. Mar Drugs 2014; 12:2539-89. [PMID: 24798925 PMCID: PMC4052305 DOI: 10.3390/md12052539] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/10/2014] [Accepted: 04/16/2014] [Indexed: 12/19/2022] Open
Abstract
Marine invertebrates produce a plethora of bioactive compounds, which serve as inspiration for marine biotechnology, particularly in drug discovery programs and biomaterials development. This review aims to summarize the potential of drugs derived from marine invertebrates in the field of neuroscience. Therefore, some examples of neuroprotective drugs and neurotoxins will be discussed. Their role in neuroscience research and development of new therapies targeting the central nervous system will be addressed, with particular focus on neuroinflammation and neurodegeneration. In addition, the neuronal growth promoted by marine drugs, as well as the recent advances in neural tissue engineering, will be highlighted.
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Affiliation(s)
- Clara Grosso
- REQUIMTE/Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, no. 228, 4050-313 Porto, Portugal.
| | - Patrícia Valentão
- REQUIMTE/Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, no. 228, 4050-313 Porto, Portugal.
| | - Federico Ferreres
- Research Group on Quality, Safety and Bioactivity of Plant Foods, Department of Food Science and Technology, CEBAS (CSIC), P.O. Box 164, Campus University Espinardo, Murcia 30100, Spain.
| | - Paula B Andrade
- REQUIMTE/Laboratory of Pharmacognosy, Department of Chemistry, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, no. 228, 4050-313 Porto, Portugal.
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16
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Itoh T, Montgomery TP, Recio A, Krische MJ. Asymmetric alcohol C-H allylation and syn-crotylation: C9-C20 of tetrafibricin. Org Lett 2014; 16:820-3. [PMID: 24422777 PMCID: PMC3932543 DOI: 10.1021/ol403566w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The C9-C20 segment of the fibrinogen receptor inhibitor tetrafibricin was prepared in 10 steps (longest linear sequence). Ruthenium catalyzed enantioselective syn-crotylation is used to construct C9-C13. Iridium catalyzed asymmetric alcohol C-H allylation of a commercial malic acid derived alcohol is used to construct C14-C20. Recovery and recycling of the iridium catalyst is described.
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Affiliation(s)
- Takahiko Itoh
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, TX 78712
| | - T. Patrick Montgomery
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, TX 78712
| | - Antonio Recio
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, TX 78712
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry and Biochemistry, Austin, TX 78712
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Kamptmann SB, Brückner R. Stereocontrolled Synthesis of a Cn-Cn+7Building Block (“Eastern Moiety”) for the Unnatural Enantiomers of Important Polyol,Polyene Antibiotics Based on a Ring-Closing Metathesis and an Aldol Addition of a Lactone Enolate. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300183] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Persich P, Llaveria J, Lhermet R, de Haro T, Stade R, Kondoh A, Fürstner A. Increasing the Structural Span of Alkyne Metathesis. Chemistry 2013; 19:13047-58. [DOI: 10.1002/chem.201302320] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Indexed: 12/22/2022]
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Sittiwong W, Richardson MW, Schiaffo CE, Fisher TJ, Dussault PH. Re2O7-catalyzed reaction of hemiacetals and aldehydes with O-, S-, and C-nucleophiles. Beilstein J Org Chem 2013; 9:1526-32. [PMID: 23946852 PMCID: PMC3740507 DOI: 10.3762/bjoc.9.174] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 07/08/2013] [Indexed: 11/23/2022] Open
Abstract
Re(VII) oxides catalyze the acetalization, monoperoxyacetalization, monothioacetalization and allylation of hemiacetals. The reactions, which take place under mild conditions and at low catalyst loadings, can be conducted using hemiacetals, the corresponding O-silyl ethers, and, in some cases, the acetal dimers. Aldehydes react under similar conditions to furnish good yields of dithioacetals. Reactions of hemiacetals with nitrogen nucleophiles are unsuccessful. 1,2-Dioxolan-3-ols (peroxyhemiacetals) undergo Re(VII)-promoted etherification but not allylation. Hydroperoxyacetals (1-alkoxyhydroperoxides) undergo selective exchange of the alkoxide group in the presence of either Re2O7 or a Brønsted acid.
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Affiliation(s)
- Wantanee Sittiwong
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588-0304, USA
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Tungen JE, Nolsøe JMJ, Hansen TV. Asymmetric Iodolactonization Utilizing Chiral Squaramides. Org Lett 2012; 14:5884-7. [DOI: 10.1021/ol302798g] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Jørn E. Tungen
- School of Pharmacy, Department of Pharmaceutical Chemistry, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo, Norway
| | - Jens M. J. Nolsøe
- School of Pharmacy, Department of Pharmaceutical Chemistry, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo, Norway
| | - Trond V. Hansen
- School of Pharmacy, Department of Pharmaceutical Chemistry, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo, Norway
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Jackson JJ, Stivala CE, Iorga BI, Molgó J, Zakarian A. Stability of cyclic imine toxins: interconversion of pinnatoxin amino ketone and pinnatoxin A in aqueous media. J Org Chem 2012; 77:10435-40. [PMID: 23116445 DOI: 10.1021/jo301632d] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pinnatoxins belong to the cyclic imine (CI) group of marine toxins with a unique toxicological profile. The need for structural integrity of the aliphatic 7-membered cyclic imine for the potent bioactivity of pinnatoxins has been experimentally demonstrated. In this study, we probe interconversion of the natural cyclic imine and its open form, pinnatoxin A amino ketone (PnTX AK), under physiologically relevant aqueous conditions. Our studies demonstrate the high stability of PnTX A. The unusual stability of the imine ring in PnTX A has implications for its oral toxicity and detoxification. These studies, as well the access to PnTX amino ketone, were enabled by the total synthesis of (+)-pinnatoxin A completed previously in our laboratory.
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Affiliation(s)
- Jeffrey J Jackson
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510, USA
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