1
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Singh S, Kumar R, Dubey NN, Appayee C. Synthesis and application of chiral cis-2,5-disubstituted pyrrolidine organocatalysts. Chem Commun (Camb) 2024. [PMID: 39076133 DOI: 10.1039/d4cc03132f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2024]
Abstract
The first synthesis of chiral cis-2,5-disubstituted pyrrolidine organocatalysts is described. Their application for the enantioselective Michael addition of nitromethane to α,β-unsaturated aldehydes with excellent yield (up to 91%) and enantioselectivity (up to >99% ee) is demonstrated. Another catalytic application for the reaction of 2,4-hexadienal with nitrostyrene is also showcased.
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Affiliation(s)
- Suraj Singh
- Department of Chemistry, Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat 382055, India.
| | - Rohtash Kumar
- Department of Chemistry, Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat 382055, India.
| | - Navneet Nandgopal Dubey
- Department of Chemistry, Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat 382055, India.
| | - Chandrakumar Appayee
- Department of Chemistry, Indian Institute of Technology Gandhinagar, Palaj, Gandhinagar, Gujarat 382055, India.
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2
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Jaunsleine K, Supe L, Spura J, van Beek S, Sandström A, Olsen J, Halleskog C, Bengtsson T, Mutule I, Pelcman B. Development of novel β 2-adrenergic receptor agonists for the stimulation of glucose uptake - The importance of chirality and ring size of cyclic amines. Bioorg Med Chem Lett 2024; 97:129562. [PMID: 37967654 DOI: 10.1016/j.bmcl.2023.129562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 10/05/2023] [Accepted: 11/11/2023] [Indexed: 11/17/2023]
Abstract
β2-Adrenergic receptor (β2AR) agonists have been reported to stimulate glucose uptake (GU) by skeletal muscle cells and are therefore highly interesting as a possible treatment for type 2 diabetes (T2D). The chirality of compounds often has a great impact on the activity of β2AR agonists, although this has thus far not been investigated for GU. Here we report the GU for a selection of synthesized acyclic and cyclic β-hydroxy-3-fluorophenethylamines. For the N-butyl and the N-(2-pentyl) compounds, the (R) and (R,R) (3d and 7e) stereoisomers induced the highest GU. When the compounds contained a saturated nitrogen containing 4- to 7-membered heterocycle, the (R,R,R) enantiomer of the azetidine (8a) and the pyrrolidine (9a) had the highest activity. Altogether, these results provide pivotal information for designing novel β2AR agonist for the treatment of T2D.
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Affiliation(s)
- Krista Jaunsleine
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga LV-1006, Latvia
| | - Linda Supe
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga LV-1006, Latvia
| | - Jana Spura
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga LV-1006, Latvia
| | - Sten van Beek
- Atrogi AB, Tomtebodavägen 6, SE-171 65 Solna, Sweden
| | | | - Jessica Olsen
- Atrogi AB, Tomtebodavägen 6, SE-171 65 Solna, Sweden
| | | | - Tore Bengtsson
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Ilga Mutule
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga LV-1006, Latvia.
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3
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Liu L, Jiang M, Zhang Q, Chen H, Zhang Y, Zhang J. Asymmetric total synthesis strategies of halichlorine and pinnaic acid. RSC Adv 2023; 13:33754-33769. [PMID: 38019985 PMCID: PMC10654894 DOI: 10.1039/d3ra06955a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 11/09/2023] [Indexed: 12/01/2023] Open
Abstract
Halichlorine and pinnaic acid are structurally related natural alkaloids isolated from different marine organisms. These two marine alkaloids bearing a 6-azaspiro[4.5]decane skeleton demonstrate a wide range of biological effects. It is this kind of unique structure and potentially valuable biological activity that have prompted strong synthetic interest, making it a research focus in recent years. Since the first total synthesis of halichlorine and pinnaic acid completed by Danishefsky's group, many groups have reported their outstanding synthesis methods especially the asymmetric synthesis strategies. This review summarizes the asymmetric synthesis strategies of halichlorine and pinnaic acid using a 6-azaspiro[4.5]decane skeleton as the key intermediate, which can provide some guidance for related work.
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Affiliation(s)
- Lu Liu
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Minghua Jiang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Qingkang Zhang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Hong Chen
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
| | - Yifu Zhang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
- Northwest Collaborative Innovation Center for Traditional Chinese Medicine Co-Constructed by Gansu Province & MOE of PRC Lanzhou 730000 P. R. China
| | - Jian Zhang
- School of Pharmacy, Gansu University of Chinese Medicine Lanzhou 730000 P. R. China
- Northwest Collaborative Innovation Center for Traditional Chinese Medicine Co-Constructed by Gansu Province & MOE of PRC Lanzhou 730000 P. R. China
- Key Laboratory of Chemistry and Quality for TCM of the College of Gansu Province Lanzhou 730000 P. R. China
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4
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Kolaříková V, Rybáčková M, Svoboda M, Kvíčala J. Ring-closing metathesis of prochiral oxaenediynes to racemic 4-alkenyl-2-alkynyl-3,6-dihydro-2 H-pyrans. Beilstein J Org Chem 2020; 16:2757-2768. [PMID: 33224302 PMCID: PMC7670115 DOI: 10.3762/bjoc.16.226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/28/2020] [Indexed: 11/23/2022] Open
Abstract
The prochiral 4-(allyloxy)hepta-1,6-diynes, optionally modified in the positions 1 and 7 with an alkyl or ester group, undergo a chemoselective ring-closing enyne metathesis yielding racemic 4-alkenyl-2-alkynyl-3,6-dihydro-2H-pyrans. Among the catalysts tested, Grubbs 1st generation precatalyst in the presence of ethene (Mori conditions) gave superior results compared to the more stable Grubbs or Hoveyda-Grubbs 2nd generation precatalysts. This is probably caused by a suppression of the subsequent side-reactions of the enyne metathesis product with ethene. On the other hand, the 2nd generation precatalysts gave better yields in the absence of ethene. The metathesis products, containing both a triple bond and a conjugated system, can be successfully orthogonally modified. For example, the metathesis product of 5-(allyloxy)nona-2,7-diyne reacted chemo- and stereoselectively in a Diels-Alder reaction with N-phenylmaleimide affording the tricyclic products as a mixture of two separable diastereoisomers, the configuration of which was estimated by DFT computations. The reported enediyne metathesis paves the way to the enantioselective enyne metathesis yielding chiral building blocks for compounds with potential biological activity, e.g., norsalvinorin or cacospongionolide B.
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Affiliation(s)
- Viola Kolaříková
- Department of Organic Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Markéta Rybáčková
- Department of Organic Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Martin Svoboda
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo nám. 2, 166 10 Prague 6, Czech Republic
| | - Jaroslav Kvíčala
- Department of Organic Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
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5
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Lacharity JJ, Mailyan AK, Chen KY, Zakarian A. Concise Synthesis of (+)-[ 13 C 4 ]-Anatoxin-a by Dynamic Kinetic Resolution of a Cyclic Iminium Ion. Angew Chem Int Ed Engl 2020; 59:11364-11368. [PMID: 32304178 PMCID: PMC7409530 DOI: 10.1002/anie.202004464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 04/17/2020] [Indexed: 11/11/2022]
Abstract
An asymmetric total synthesis of [13 C4 ]-anatoxin-a ([13 C4 ]-1) has been developed from commercially available ethyl [13 C4 ]-acetoacetate ([13 C4 ]-15). The unique requirements associated with isotope incorporation inspired a new, robust, and highly scalable route, providing access to 0.110 g of this internal standard for use in the detection and precise quantification of anatoxin-a in freshwater. A highlight of the synthesis is a method that leverages a cyclic iminium ion racemization to achieve dynamic kinetic resolution in an enantioselective Morita-Baylis-Hillman (MBH) cyclization.
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Affiliation(s)
- Jacob J Lacharity
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
| | - Artur K Mailyan
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
| | - Karen Y Chen
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106-9510, USA
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6
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Lacharity JJ, Mailyan AK, Chen KY, Zakarian A. Concise Synthesis of (+)‐[
13
C
4
]‐Anatoxin‐a by Dynamic Kinetic Resolution of a Cyclic Iminium Ion. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202004464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Jacob J. Lacharity
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
| | - Artur K. Mailyan
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
| | - Karen Y. Chen
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
| | - Armen Zakarian
- Department of Chemistry and Biochemistry University of California Santa Barbara CA 93106-9510 USA
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7
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Suravarapu SR, Peter B, Renaud P. Radical-mediated hydroalkylation of 2-vinylpyrrolidine derivatives: a versatile entry into indolizidine alkaloids. Sci China Chem 2019. [DOI: 10.1007/s11426-019-9598-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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8
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Enantioselective addition of diethylzinc to aldehydes catalyzed by 5-cis-substituted proline derivatives. Tetrahedron 2019. [DOI: 10.1016/j.tet.2018.11.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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9
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A unified approach to the synthesis of both enantiomers of anatoxin-a and homoanatoxin-a cyanotoxins. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.04.057] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Abstract
Diverse structural types of natural products and their mimics have served as targets of opportunity in our laboratory to inspire the discovery and development of new methods and strategies to assemble polyfunctional and polycyclic molecular architectures. Furthermore, our efforts toward identifying novel compounds having useful biological properties led to the creation of new targets, many of which posed synthetic challenges that required the invention of new methodology. In this Perspective, selected examples of how we have exploited a diverse range of natural products and their mimics to create, explore, and solve a variety of problems in chemistry and biology will be discussed. The journey was not without its twists and turns, but the unexpected often led to new revelations and insights. Indeed, in our recent excursion into applications of synthetic organic chemistry to neuroscience, avoiding the more-traveled paths was richly rewarding.
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Affiliation(s)
- Stephen F Martin
- Department of Chemistry, The University of Texas at Austin , Austin, Texas 78712, United States
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11
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Hu Y, Bai M, Yang Y, Zhou Q. Metal-catalyzed enyne cycloisomerization in natural product total synthesis. Org Chem Front 2017. [DOI: 10.1039/c7qo00702g] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Enyne cycloisomerization has become a powerful and attractive strategy for the construction of cyclic compounds, thus possessing great potential for applications in total synthesis of natural products and pharmaceuticals.
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Affiliation(s)
- Ying Hu
- College of Chemistry and Molecular Sciences
- Wuhan University
- Wuhan
- P.R. China
| | - Miao Bai
- College of Chemistry and Molecular Sciences
- Wuhan University
- Wuhan
- P.R. China
| | - Ying Yang
- College of Chemistry and Molecular Sciences
- Wuhan University
- Wuhan
- P.R. China
| | - Qianghui Zhou
- College of Chemistry and Molecular Sciences
- Wuhan University
- Wuhan
- P.R. China
- The Institute for Advanced Studies
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12
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Kono M, Harada S, Hamada Y, Nemoto T. Formal amide insertion strategy for the synthesis of anatoxin-a using rhodium catalysis. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.01.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Cheng B, Sunderhaus JD, Martin SF. Applications of Ring Closing Metathesis. Total Synthesis of (±)-Pseudotabersonine. Tetrahedron 2015; 71:7323-7331. [PMID: 26300565 DOI: 10.1016/j.tet.2015.04.082] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A novel approach to the Aspidosperma family of alkaloids was developed and applied to a concise total synthesis of (±)-pseudotabersonine that was accomplished in 11 steps. Key transformations include a stepwise variant of a Mannich-like multicomponent assembly process, a double ring-closing metathesis sequence, and a one-pot deprotection/cyclization reaction.
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Affiliation(s)
- Bo Cheng
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712
| | - James D Sunderhaus
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712
| | - Stephen F Martin
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712
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14
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Kuznetsov NY, Bubnov YN. Ruthenium-catalyzed intramolecular metathesis of dienes and its application in the synthesis of bridged and spiro azabicycles. RUSSIAN CHEMICAL REVIEWS 2015. [DOI: 10.1070/rcr4478] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Recent Advances in Application of Amino Acids: Key Building Blocks in Design and Syntheses of Heterocyclic Compounds. ADVANCES IN HETEROCYCLIC CHEMISTRY 2015. [DOI: 10.1016/bs.aihch.2015.02.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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16
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Pace V, Holzer W, Olofsson B. Increasing the Reactivity of Amides towards Organometallic Reagents: An Overview. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400630] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Chu S, Wallace S, Smith MD. A Cascade Strategy Enables a Total Synthesis of (−)-Gephyrotoxin. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201409038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Chu S, Wallace S, Smith MD. A Cascade Strategy Enables a Total Synthesis of (−)-Gephyrotoxin. Angew Chem Int Ed Engl 2014; 53:13826-9. [DOI: 10.1002/anie.201409038] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Indexed: 01/08/2023]
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19
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Xiao KJ, Wang Y, Huang YH, Wang XG, Huang PQ. A Direct and General Method for the Reductive Alkylation of Tertiary Lactams/Amides: Application to the Step Economical Synthesis of Alkaloid (−)-Morusimic Acid D. J Org Chem 2013; 78:8305-11. [DOI: 10.1021/jo4007656] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kai-Jiong Xiao
- Department of Chemistry,
College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People’s Republic of China
| | - Yu Wang
- Department of Chemistry,
College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People’s Republic of China
| | - Ying-Hong Huang
- Department of Chemistry,
College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People’s Republic of China
| | - Xiao-Gang Wang
- Department of Chemistry,
College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People’s Republic of China
| | - Pei-Qiang Huang
- Department of Chemistry,
College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People’s Republic of China
- The State Key Laboratory of
Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People’s Republic of China
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20
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Evolution of the Total Syntheses of Batzellasides the First Marine Piperidine Iminosugar. Nat Prod Commun 2013. [DOI: 10.1177/1934578x1300800729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Batzellasides A-C are C-alkylated piperidine iminosugars isolated from a sponge Batzella sp. The first total synthesis of (+)-batzellaside B was achieved by employing a chiral pool approach starting from L-arabinose for the construction of a piperidine ring system. Subsequently a practical second-generation synthesis was developed by utilizing a Sharpless asymmetric dihydroxylation for the preparation of the common piperidine intermediate elaborated in the first-generation synthesis. The overall yield of batzellaside B was improved to 3.3% by introducing the exocyclic C8 stereocenter via facial selective hydride addition to a linear ketone. These syntheses allowed for the determination of the absolute stereochemistry of this natural product as well as for providing precious samples which would pave the way for further biological studies.
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21
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Martin SF. Strategies for the Synthesis of Alkaloids and Novel Nitrogen Heterocycles. ADVANCES IN HETEROCYCLIC CHEMISTRY 2013. [DOI: 10.1016/b978-0-12-408100-0.00003-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
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22
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Synthesis of oxacyclic dienes via ring-closing enyne metathesis: difference in construction of eight-membered rings. Tetrahedron Lett 2012. [DOI: 10.1016/j.tetlet.2012.04.107] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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23
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Sahn JJ, Martin SF. Facile Syntheses of Substituted, Conformationally-Constrained Benzoxazocines and Benzazocines via Sequential Multicomponent Assembly and Cyclization. Tetrahedron Lett 2011; 52:6855-6858. [PMID: 22711939 PMCID: PMC3375694 DOI: 10.1016/j.tetlet.2011.10.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A multicomponent assembly process (MCAP) was utilized to prepare versatile intermediates that are suitably functionalized for subsequent cyclizations via Ullmann and Heck reactions to efficiently construct substituted 2,6-methanobenzo[b][1,5]oxazocines and 1,6-methanobenzo[c]azocines, respectively. The intramolecular Ullmann cyclization was conducted in tandem with an intermolecular arylation that enabled the rapid syntheses of a number of O-functionalized methanobenzoxazocines.
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Affiliation(s)
- James J Sahn
- Department of Chemistry and Biochemistry and Texas Institute for Drug and Diagnostic Development, The University of Texas, Austin, TX, 78712, USA
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24
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Reddy BS, Reddy AB, Reddy GR, Reddy PR. Synthesis and Antibacterial Activity of Novel [3-(4-substitutedphenylamino)-8-azabicyclo [3.2.1] oct-8yl]-phenyl-methanone Derivatives. JOURNAL OF THE KOREAN CHEMICAL SOCIETY-DAEHAN HWAHAK HOE JEE 2011. [DOI: 10.5012/jkcs.2011.55.6.969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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25
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Orr STM, Tian J, Niggemann M, Martin SF. Novel approach to the lundurine alkaloids: synthesis of the tetracyclic core. Org Lett 2011; 13:5104-7. [PMID: 21888327 DOI: 10.1021/ol201980r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The tetracyclic core of the lundurine family of alkaloids has been synthesized by a novel approach that features a double ring-closing olefin metathesis to form the five-and eight-membered rings.
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Affiliation(s)
- Suvi T M Orr
- Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712, USA
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26
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Cheng G, Wang X, Zhu R, Shao C, Xu J, Hu Y. Total synthesis of (-)-cocaine and (-)-ferruginine. J Org Chem 2011; 76:2694-700. [PMID: 21391709 DOI: 10.1021/jo200069m] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Total synthesis of tropane alkaloids (-)-cocaine and (-)-ferruginine were accomplished in nine steps each and in 55% and 46% overall yields, respectively, starting from the known Betti base derivative (+)-(7aR,10R,12S)-10-(1H-benzotriazol-1-yl)-7a,8,9,10-tetrahydro-12-phenyl-12H-naphtho[1,2-e]pyrrolo[2,1-b][1,3]oxazine. In this novel route, RCM reaction and 1,3-dipolar cycloaddition were employed as key steps for the enantioselective construction of tropane skeleton and the regioselective introduction of 3-bromo-2-isoxazoline ring as masked cis-2,3-disubstituents. To obtain the desired precursor (2S,5R)-2-allyl-5-vinylpyrrolidine for RCM reaction, we developed a general and practical method for the preparation of enantiopure cis-2,5-disubstituted pyrrolidines bearing alkene- and/or alkyne-containing substituents. We also offered two highly efficient pathways for the conversion of the 3-bromo-2-isoxazoline ring into the desired cis-2,3-disubstituted groups in (-)-cocaine and (-)-ferruginine.
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Affiliation(s)
- Guolin Cheng
- Department of Chemistry, Tsinghua University, Beijing 100084, People's Republic of China
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27
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Xiao KJ, Wang Y, Ye KY, Huang PQ. Versatile one-pot reductive alkylation of lactams/amides via amide activation: application to the concise syntheses of bioactive alkaloids (±)-bgugaine, (±)-coniine, (+)-preussin, and (-)-cassine. Chemistry 2011; 16:12792-6. [PMID: 20938943 DOI: 10.1002/chem.201002054] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Kai-Jiong Xiao
- Department of Chemistry and The Key Laboratory for Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, PR China
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28
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Cheng B, Sunderhaus JD, Martin SF. Concise total synthesis of (+/-)-pseudotabersonine via double ring-closing metathesis strategy. Org Lett 2010; 12:3622-5. [PMID: 20704405 DOI: 10.1021/ol101356u] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A concise synthesis of (+/-)-pseudotabersonine from commercially available 1-(phenylsulfonyl)-3-indolecarboxaldehyde has been accomplished. This synthesis features the convergent assembly of a key intermediate via a stepwise variant of a Mannich-type multicomponent coupling process, a double ring-closing metathesis, and a one-pot deprotection/cyclization reaction.
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Affiliation(s)
- Bo Cheng
- Department of Chemistry and Biochemistry, The University of Texas, Austin, Texas 78712, USA
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29
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Neurotoxic cyanobacterial toxins. Toxicon 2010; 56:813-28. [DOI: 10.1016/j.toxicon.2009.07.036] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Revised: 07/27/2009] [Accepted: 07/30/2009] [Indexed: 11/19/2022]
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Deck JA, Martin SF. Enantioselective synthesis of (+)-isolysergol via ring-closing metathesis. Org Lett 2010; 12:2610-3. [PMID: 20462232 DOI: 10.1021/ol100819f] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first enantioselective synthesis of (+)-isolysergol was completed in 12 steps from commercially available materials by a novel approach that features a late stage microwave-mediated, diastereomeric ring-closing metathesis catalyzed by a chiral molybdenum catalyst to simultaneously form the D ring and set the stereocenter at C(8).
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Affiliation(s)
- Jason A Deck
- Department of Chemistry and Biochemistry, The University of Texas, Austin, Texas 78712, USA
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31
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Sada M, Furuyama T, Komagawa S, Uchiyama M, Matsubara S. 1,4-Addition of Bis(iodozincio)methane to α,β-Unsaturated Ketones: Chemical and Theoretical/Computational Studies. Chemistry 2010; 16:10474-81. [DOI: 10.1002/chem.201000738] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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32
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Recent Progress on Enyne Metathesis: Its Application to Syntheses of Natural Products and Related Compounds. MATERIALS 2010. [PMCID: PMC5445882 DOI: 10.3390/ma3032087] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Olefin metathesis using ruthenium carbene complexes is a useful method in synthetic organic chemistry. Enyne metathesis is also catalyzed by these complexes and various carbo- and heterocycles could be synthesized from the corresponding enynes. Dienyne metathesis, cross enyne metathesis and ring-opening enyne metathesis have been further developed. Various complicated compounds, such as the natural products and the related biologically active substances, could be synthesized using these metatheses reactions. Skeletal reorganization using the transition metals and metallotropic rearrangement are also discussed.
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33
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Mo F, Li F, Qiu D, Wang J. Enantioselective synthesis of condensed and transannular ring skeletons containing pyrrolidine moiety. Tetrahedron 2010. [DOI: 10.1016/j.tet.2009.12.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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34
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Takao KI, Tadano KI. Synthesis of Nitrogen- and Oxygen-Bridged Seven- to Ten-Membered Carbocycles Using Metathesis Reactions. HETEROCYCLES 2010. [DOI: 10.3987/rev-10-672] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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35
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Liu WJ, Ye JL, Huang PQ. A flexible approach for the asymmetric syntheses of hyacinthacines A2, A3 and structural confirmation of hyacinthacine A3. Org Biomol Chem 2010; 8:2085-91. [DOI: 10.1039/b926741g] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Toyooka N, Zhou D, Nemoto H, Tezuka Y, Kadota S, Andriamaharavo NR, Garraffo HM, Spande TF, Daly JW. Efficient enantio- and diastereodivergent synthesis of poison-frog alkaloids 251O and trans-223B. J Org Chem 2009; 74:6784-91. [PMID: 19637860 DOI: 10.1021/jo901100m] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An efficient and flexible synthesis of poison-frog alkaloids 251O and trans-223B has been achieved by using for both alkaloids an enantiodivergent process starting from the common lactam 1. The relative stereochemistry of 251O and trans-223B was determined to be 7 (R = n-C(7)H(15), R' = n-Pr) and 14 by the present enantioselective synthesis.
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Affiliation(s)
- Naoki Toyooka
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194, Japan.
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37
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McDermott TS, Bhagavatula L, Borchardt TB, Engstrom KM, Gandarilla J, Kotecki BJ, Kruger AW, Rozema MJ, Sheikh AY, Wagaw SH, Wittenberger SJ. Development of a Scalable Synthesis of Dipeptidyl Peptidase-4 Inhibitor ABT-279. Org Process Res Dev 2009. [DOI: 10.1021/op900197r] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Todd S. McDermott
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Lakshmi Bhagavatula
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Thomas B. Borchardt
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Kenneth M. Engstrom
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Jorge Gandarilla
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Brian J. Kotecki
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Albert W. Kruger
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Michael J. Rozema
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Ahmad Y. Sheikh
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Seble H. Wagaw
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
| | - Steven J. Wittenberger
- Abbott Laboratories, Global Pharmaceuticals R&D, Formulation Sciences - Solids, 200 Abbott Park Road, D-R4P7, Building AP31, Abbott Park, Illinois 60064, Abbott Laboratories, Global Pharmaceuticals R&D, Process R&D, 1401 Sheridan Road, D-R450, Building R8, North Chicago, Illinois 60064, and Abbott Laboratories, Global Pharmaceuticals R&D, Solid State Chemistry, 1401 Sheridan Road, D-R452, Building R13, North Chicago, Illinois 60064
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39
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40
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Lin GJ, Huang PQ. A concise and fully selective synthesis of the ant venom alkaloid (3S,5R,8S,9S)-3-butyl-5-propyl-8-hydroxyindolizidine. Org Biomol Chem 2009; 7:4491-5. [DOI: 10.1039/b912190k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Toyooka N, Zhou D, Nemoto H, Yamaguchi K, Tsuneki H, Wada T, Sasaoka T, Sakai H, Tezuka Y, Kadota S, H. Jones T, Martin Garraffo H, F. Spande T. Synthesis, Determination of the Absolute Stereochemistry, and Evaluations at the Nicotinic Acetylcholine Receptors of a Hydroxyindolizidine Alkaloid from the Ant Myrmicaria melanogaster. HETEROCYCLES 2009. [DOI: 10.3987/com-08-s(d)16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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42
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Onomura O, Kirira PG, Tanaka T, Tsukada S, Matsumura Y, Demizu Y. Diastereoselective arylation of l-proline derivatives at the 5-position. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.06.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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43
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Miller KA, Shanahan CS, Martin SF. The Pauson-Khand Reaction as a New Entry to the Synthesis of Bridged Bicyclic Heterocycles: Application to the Enantioselective Total Synthesis of (-)-Alstonerine. Tetrahedron 2008; 64:6884-6900. [PMID: 19122869 DOI: 10.1016/j.tet.2008.02.066] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The first application of the Pauson-Khand reaction (PKR) to the synthesis of azabridged bicyclic structures is described. Compounds containing azabicyclo[3.3.1]nonane and azabicyclo[3.2.1]octane rings fused to cyclopentenones were efficiently constructed via the PKR of cis-2,6-disubstituted N-acyl piperidine enyne substrates, many of which can be readily prepared from 4-methoxypyridine in a few steps. Moreover, the PKR of cis-2,6-disubstituted piperazine enynes allowed the preparation of diazabicyclo[3.3.1]nonanes fused to cyclopentenones. This new strategy for the synthesis of azabridged bicyclic frameworks was exploited as a key step in a concise, enantioselective total synthesis of the macroline alklaoid (-)-alstonerine.
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Affiliation(s)
- Kenneth A Miller
- Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300 Austin, TX 78712-0165
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44
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Toyooka N, Zhou D, Nemoto H. Enantioselective syntheses of (-)- and (+)-monomorine I. J Org Chem 2008; 73:4575-7. [PMID: 18507441 DOI: 10.1021/jo800593n] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A concise enantioselective total synthesis of unnatural (-)-monomorine I has been achieved starting from lactam 2 in 54% overall yield. Natural (+)-monomorine I was also synthesized.
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Affiliation(s)
- Naoki Toyooka
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama, Japan.
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45
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Simila STM, Martin SF. Toward the total synthesis of FR901483: concise synthesis of the azatricyclic skeleton. J Org Chem 2007; 72:5342-9. [PMID: 17555359 PMCID: PMC2536713 DOI: 10.1021/jo070732a] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A concise synthesis of the azatricyclic core of FR901483 has been accomplished using a novel strategy that involves a nucleophilic addition to an N-acyl iminium ion, a ring-closing metathesis, a diastereoselective hydroboration, and a lactone-lactam rearrangement that worked well in a preliminary model study. Extension of this approach to the synthesis of a more highly functionalized intermediate that could be transformed into (-)-FR901483 first required the development of a new protecting group, the 1-ethylallyloxycarbamate group, for amines that may be removed under mild conditions. However, because the stereoselectivity in a key step in which a functionalized allyl zinc reagent was added to an intermediate hydroxy-substituted imine was low, this route to (-)-FR901483 is no longer being pursued.
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46
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Abstract
This review provides an overview of ruthenium vinyl carbene reactivity as it relates to enyne metathesis. Methods for the synthesis of metathesis-active and metathesis-inactive complexes are also summarized. Some of the early hypotheses about vinyl carbene intermediates in enyne metatheses were tested in the arena of synthetic chemistry and subsequently led to mechanistic studies. In these two areas, studies from the author's labs are described. There are still many unresolved questions in enyne metathesis that trace back to vinyl carbene reactivity. Hopefully this review will stimulate further investigation into vinyl carbene reactivity which should further refine our understanding of catalytic enyne metathesis.
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Affiliation(s)
- Steven T Diver
- Department of Chemistry, State University of New York at Buffalo, Buffalo, NY 14260-3000,
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47
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Rawn DFK, Niedzwiadek B, Lau BPY, Saker M. Anatoxin-a and its metabolites in blue-green algae food supplements from Canada and Portugal. J Food Prot 2007; 70:776-9. [PMID: 17388076 DOI: 10.4315/0362-028x-70.3.776] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Blue-green algae and spirulina are marketed in health food stores and over the Internet as food supplements in Canada, the United States, and Europe. The reported benefits of consuming these products include improved digestion, strengthening of the immune system, and relief from the symptoms of attention deficit disorder. Some of these products have been found to contain elevated concentrations of microcystins, which are known hepatotoxins. In addition to producing microcystins, Anabaena sp. and Aphanizomenon sp. also produce the potent neurotoxin anatoxin-a. Samples of food supplements containing blue-green algae and spirulina were collected in Portugal and from urban centers across Canada in 2005. Extracts of these supplements were analyzed to determine the presence and concentrations of anatoxin-a and its two main metabolites, dihydroanatoxin-a and epoxyanatoxin-a. Initial analyses were performed using high-performance liquid chromatography (HPLC) with fluorescence detection, and confirmation required the use of LC with tandem mass spectrometry (LC-MS-MS). The HPLC with fluorescence detection indicated no anatoxin-a, but four samples were suspected to contain either dihydroanatoxin-a or epoxyanatoxin-a at 0.1 to 0.2 microg/g. LC-MS-MS results, however, indicated no trace of either transformation product in any sample analyzed. The detection limits for anatoxin-a, dihydroanatoxin-a, and epoxyanatoxin-a were similar for both fluorescence detection (0.2 to 0.3, 0.4 to 1.4, and 0.2 to 1.5 pg on the column, respectively) and mass spectrometry (0.3 to 1.5, 0.3 to 0.8, and 0.5 to 0.8 pg on the column, respectively). Because of the higher specificity of the LC-MS-MS analysis, all tested food supplement samples were considered free of anatoxin-a and its transformation products.
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Affiliation(s)
- Dorothea F K Rawn
- Food Research Division, Food Directorate, Health Products and Food Branch, Health Canada, 2203D, 251 Sir Frederick Banting Driveway, Tunney's Pasture, Ottawa, Ontario, Canada K1A 0K9.
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48
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Villar H, Frings M, Bolm C. Ring closing enyne metathesis: A powerful tool for the synthesis of heterocycles. Chem Soc Rev 2007; 36:55-66. [PMID: 17173145 DOI: 10.1039/b508899m] [Citation(s) in RCA: 239] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ring closing metathesis (RCM) is a powerful method in organic synthesis for the preparation of cyclic compounds by formation of new carbon-carbon bonds. In the past years a particular subclass of the RCM, the ring closing enyne metathesis (RCEYM), has attracted attention due to its synthetic potential in the generation of ring structures with 1,3-diene moieties, which can subsequently be further functionalised. In this tutorial review mechanistic considerations will be described and the synthetic power of this useful and attractive carbon-carbon bond forming reaction will be illustrated by recent examples of RCEYM applications in the preparation of heterocyclic compounds.
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Affiliation(s)
- Hélène Villar
- Institut für Organische Chemie der RWTH Aachen, Landoltweg 1, 52074 Aachen, Germany
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50
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Kummer DA, Brenneman JB, Martin SF. Domino intramolecular enyne metathesis/cross metathesis approach to the xanthanolides. Enantioselective synthesis of (+)-8-epi-xanthatin. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.05.019] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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