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Bouthillette LM, Aniebok V, Colosimo DA, Brumley D, MacMillan JB. Nonenzymatic Reactions in Natural Product Formation. Chem Rev 2022; 122:14815-14841. [PMID: 36006409 DOI: 10.1021/acs.chemrev.2c00306] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Biosynthetic mechanisms of natural products primarily depend on systems of protein catalysts. However, within the field of biosynthesis, there are cases in which the inherent chemical reactivity of metabolic intermediates and substrates evades the involvement of enzymes. These reactions are difficult to characterize based on their reactivity and occlusion within the milieu of the cellular environment. As we continue to build a strong foundation for how microbes and higher organisms produce natural products, therein lies a need for understanding how protein independent or nonenzymatic biosynthetic steps can occur. We have classified such reactions into four categories: intramolecular, multicomponent, tailoring, and light-induced reactions. Intramolecular reactions is one of the most well studied in the context of biomimetic synthesis, consisting of cyclizations and cycloadditions due to the innate reactivity of the intermediates. There are two subclasses that make up multicomponent reactions, one being homologous multicomponent reactions which results in dimeric and pseudodimeric natural products, and the other being heterologous multicomponent reactions, where two or more precursors from independent biosynthetic pathways undergo a variety of reactions to produce the mature natural product. The third type of reaction discussed are tailoring reactions, where postmodifications occur on the natural products after the biosynthetic machinery is completed. The last category consists of light-induced reactions involving ecologically relevant UV light rather than high intensity UV irradiation that is traditionally used in synthetic chemistry. This review will cover recent nonenzymatic biosynthetic mechanisms and include sources for those reviewed previously.
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Affiliation(s)
- Leah M Bouthillette
- Deparment of Chemistry and Biochemistry, University of California, Santa Cruz, 1156 High Street, Santa Cruz, California 95064, United States
| | - Victor Aniebok
- Deparment of Chemistry and Biochemistry, University of California, Santa Cruz, 1156 High Street, Santa Cruz, California 95064, United States
| | - Dominic A Colosimo
- Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390 United States
| | - David Brumley
- Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390 United States
| | - John B MacMillan
- Deparment of Chemistry and Biochemistry, University of California, Santa Cruz, 1156 High Street, Santa Cruz, California 95064, United States.,Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390 United States
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Liang XT, Sun BC, Zhang N, Zhang ZC, Li YH, Xu QQ, Liu C, Chen JH, Yang Z. Asymmetric Total Synthesis of (-)-Spirochensilide A, Part 2: The Final Phase and Completion. J Org Chem 2021; 86:2158-2172. [PMID: 33481592 DOI: 10.1021/acs.joc.0c02510] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The final phase of the total synthesis of (-)-spirochensilide A is described. A tungsten-mediated cyclopropene-based Pauson-Khand reaction was developed to form the spiral CD ring system with desired stereochemistry at the C13 quaternary center. Other important steps enabling completion of this synthesis included an intermolecular aldol condensation to link the ABCD core with the EF fragment and a Cu-mediated 1,4-addition to stereoselectively install the C21 stereogenic center. The chemistry developed for this total synthesis of (-)-spirochensilide A (1) will aid the synthesis of polycyclic natural products bearing this unique spiral ring system.
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Affiliation(s)
- Xin-Ting Liang
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China
| | - Bao-Chuan Sun
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China
| | - Nan Zhang
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China
| | - Zhong-Chao Zhang
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yuan-He Li
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China
| | - Qian-Qian Xu
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China
| | - Chang Liu
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China
| | - Jia-Hua Chen
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China
| | - Zhen Yang
- State Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science (BNLMS), College of Chemistry and the Peking University, Beijing 100871, China.,Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China.,Shenzhen Bay Laboratory, Shenzhen 518055, China
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Bhat BA, Rashid S, Mehta G. Progress in the Total Synthesis of Natural Products Embodying Diverse Furofuranone Motifs: A New Millennium Update. ASIAN J ORG CHEM 2020. [DOI: 10.1002/ajoc.202000401] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Bilal A. Bhat
- CSIR-Medicinal Chemistry Division Indian Institute of Integrative Medicine Sanat Nagar Srinagar 190005 India
- Academy of Scientific and Innovative Research CSIR-Indian Institute of Integrative Medicine Canal Road Jammu 180001 India
| | - Showkat Rashid
- CSIR-Medicinal Chemistry Division Indian Institute of Integrative Medicine Sanat Nagar Srinagar 190005 India
- Academy of Scientific and Innovative Research CSIR-Indian Institute of Integrative Medicine Canal Road Jammu 180001 India
- School of Chemistry, University of Hyderabad Hyderabad 500046 India
| | - Goverdhan Mehta
- School of Chemistry, University of Hyderabad Hyderabad 500046 India
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Yi X, Jiang S, Qin M, Liu K, Cao P, Chen S, Deng J, Gao C. Compounds from the fruits of mangrove Sonneratia apetala: Isolation, molecular docking and antiaging effects using a Caenorhabditis elegans model. Bioorg Chem 2020; 99:103813. [PMID: 32334190 DOI: 10.1016/j.bioorg.2020.103813] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/08/2020] [Accepted: 03/31/2020] [Indexed: 01/22/2023]
Abstract
The chemical investigation of the fruits of a mangrove Sonneratia apetala collected from the Beibu Gulf led to the isolation of four new compounds, sonneradons A-D (1-4), as well as 18 known compounds (5-22). The structures of the new compounds were elucidated based on extensive spectroscopic analysis, and the structures of the known compounds were established by comparison of their spectroscopic data with those of related metabolites. The antiaging activities of all isolates were evaluated using the nematode Caenorhabditis elegans as a model organism. The results showed that 10 compounds could protect C. elegans by extending its lifespan. Compound 1 possessed the most potent effect in the anti-heat stress assay and significantly attenuated aging-related decreases in the pumping and bending of the nematodes in the healthspan assay. Molecular docking studies suggested that compound 1 was bound to the DNA binding domain of HSF-1 and promoted the conformation of HSF-1, thus strengthening the interaction between the HSF-1 and related DNA. GLN49, ASN-74, and LYS-80 of the binding region might be the key amino residues during the interaction.
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Affiliation(s)
- Xiangxi Yi
- Guangxi Botanical Garden of Medicinal Plants, Nanning 530023, China; Institutes of Marine Drugs/College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530001, China; College of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Shu Jiang
- Institutes of Marine Drugs/College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530001, China
| | - Mei Qin
- Institutes of Marine Drugs/College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530001, China
| | - Kai Liu
- Institutes of Marine Drugs/College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530001, China
| | - Pei Cao
- Institutes of Marine Drugs/College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530001, China
| | - Shimin Chen
- Guangxi Botanical Garden of Medicinal Plants, Nanning 530023, China
| | - Jiagang Deng
- Guangxi Botanical Garden of Medicinal Plants, Nanning 530023, China; Institutes of Marine Drugs/College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530001, China.
| | - Chenghai Gao
- Institutes of Marine Drugs/College of Pharmacy, Guangxi University of Chinese Medicine, Nanning 530001, China.
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Yuan C, Zhong S, Li X, Wang Y, Xun MM, Bai Y, Zhu K. Total synthesis, structural revision and biological evaluation of γ-elemene-type sesquiterpenes. Org Biomol Chem 2019; 16:7843-7850. [PMID: 30303229 DOI: 10.1039/c8ob02005a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Total synthesis and absolute configuration confirmation of γ-elemene-type sesquiterpenes, which possess vast potential for biological activities, was investigated based on a convergent synthetic strategy. A key intermediate with all functional groups of this family of natural products was accessed by an intermolecular aldol reaction and then an acetylation of a known ketone (12) derived from commercially available verbenone. The versatile intermediate can be easily transformed into structurally different γ-elemene-type sesquiterpenes based on control of base-promoted cyclization manipulation in different solvents. The utility of this robust approach is illustrated by the first syntheses of elema-1,3,7(11),8-tetraen-8,12-lactam (4') and 8β-methoxy-isogermafurenolide (6a), as well as the syntheses of elem-1,3,7,8-tetraen-8,12-olide (3) and hydroxyisogermafurenolide (5) in only 6 or 7 steps. In addition, the structure of the reported 5βH-elem-1,3,7,8-tetraen-8,12-olide (1) was revised as elem-1,3,7,8-tetraen-8,12-olide (3) by comparison of their identified datum, and the absolute configuration of elema-1,3,7(11),8-tetraen-8,12-lactam was confirmed as 4'. Furthermore, the inhibitory effect of all synthesized natural compounds and their natural analogues on cancer cell proliferation was evaluated. Among them compounds 3, 4 and 4' were found to possess potent inhibitory activity against Kasumi-1 and Pfeiffer. Meanwhile, preliminary structure-activity relationships for these compounds are discussed.
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Affiliation(s)
- Changchun Yuan
- National Demonstration Center for Experimental Chemical Engineering Comprehensive Education, School of Chemical Engineering and Technology, North University of China, Taiyuan 030000, P.R. China.
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7
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Synthesis and Structural Modification of Marine Natural Products. Molecules 2017; 22:molecules22060882. [PMID: 28587140 PMCID: PMC6152746 DOI: 10.3390/molecules22060882] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 05/23/2017] [Accepted: 05/24/2017] [Indexed: 11/16/2022] Open
Abstract
In the last decades, marine natural products (MNPs), have attracted extensive interest from both chemists and pharmacologists due to their chemical and bioactive diversities. This special issue, collecting total synthesis and structural modification of six different type of bioactive MNPs, is expected to inspire and attract more research effects invested into MNP research.
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Abstract
This review defines symmetric molecules from a synthetic perspective and shows various strategies that take advantage of molecular symmetry to construct them.
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Affiliation(s)
- Wen-Ju Bai
- Department of Chemistry
- Stanford University
- Stanford
- USA
| | - Xiqing Wang
- College of Bioscience and Biotechnology
- Yangzhou University
- Yangzhou
- China
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9
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Kotzabasaki V, Vassilikogiannakis G, Stratakis M. Total Synthesis and Structural Revision of (+)-Yaoshanenolide B. Org Lett 2016; 18:4982-4985. [PMID: 27622639 DOI: 10.1021/acs.orglett.6b02446] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
(+)-Yaoshanenolide B was synthesized employing as a key step an endo- and face-selective Diels-Alder reaction between natural R-(-)-α-phellandrene and the exocyclic double bond of a 5-methylene-2(5H)-furanone. The dienophile furanone was prepared by photooxygenation of a suitably substituted 2-thiophenylfuran followed by dehydration of the resulting γ-hydroxybutenolide. Through this synthesis, the initially proposed structure for (+)-yaoshanenolide B has been revised to the 1R,2S,4R,7R,1″S diastereomer.
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Affiliation(s)
| | | | - Manolis Stratakis
- Department of Chemistry, University of Crete , Voutes, 71003 Iraklion, Greece
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Kotzabasaki V, Vassilikogiannakis G, Stratakis M. Regiocontrolled Synthesis of γ-Hydroxybutenolides via Singlet Oxygen-Mediated Oxidation of 2-Thiophenyl Furans. J Org Chem 2016; 81:4406-11. [DOI: 10.1021/acs.joc.6b00660] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Manolis Stratakis
- Department of Chemistry, University of Crete, 71003 Voutes, Iraklion, Greece
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Affiliation(s)
- Ashwini A. Ghogare
- Department
of Chemistry, Brooklyn College, 2900 Bedford Avenue, Brooklyn, New York 11210, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| | - Alexander Greer
- Department
of Chemistry, Brooklyn College, 2900 Bedford Avenue, Brooklyn, New York 11210, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
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13
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Umstead WJ, Mukhina OA, Bhuvan Kumar NN, Kutateladze AG. Photoinduced Cycloadditions in the Diversity-Oriented Synthesis Toolbox: Increasing Complexity with Straightforward Postphotochemical Modifications. Aust J Chem 2015; 68:1672-1681. [PMID: 29249834 DOI: 10.1071/ch15266] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Rapid growth of complexity and unprecedented molecular architectures are realized via the excited-state intramolecular proton transfer (ESIPT) in o-acylamidobenzaldehydes and ketones followed by [4+2] or [4+4] cycloadditions with subsequent postphotochemical modifications. The approach is congruent with Diversity-Oriented Synthesis: photoprecursors are synthesized in a modular fashion allowing for up to four diversity inputs. The complexity of the primary photoproducts is further enhanced using straightforward and high-yielding postphotochemical modification steps such as reactions with nitrile oxides, nitrones, Povarov reaction, and oxa-Diels-Alder reaction.
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Affiliation(s)
- Weston J Umstead
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208
| | - Olga A Mukhina
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208
| | - N N Bhuvan Kumar
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208
| | - Andrei G Kutateladze
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208
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Wang T, Hoye TR. Diels-Alderase-free, bis-pericyclic, [4+2] dimerization in the biosynthesis of (±)-paracaseolide A. Nat Chem 2015. [PMID: 26201740 PMCID: PMC4878989 DOI: 10.1038/nchem.2281] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The natural product paracaseolide A is a tetracyclic dilactone containing six adjacent stereocenters. It has an unprecedented skeleton and occupies unique structural space among the >200,000 characterized secondary metabolites. Six different research groups have reported a chemical synthesis of this compound, five of which used a thermal, net Diels–Alder [4+2] cycloaddition and dehydration at 110 °C to access the target by dimerization of a simple butenolide precursor. Here we report that this dimerization proceeds under much milder conditions and with a different stereochemical outcome than previously recognized. This can be rationalized by invoking a bis-pericyclic transition state. Furthermore, we find that spontaneous epimerization, necessary to correct the configuration at one key stereocenter, is viable and that natural paracaseolide A is racemic. Together these facts point to the absence of enzymatic catalysis (i.e., Diels–Alderase activity) in the cycloaddition and strongly suggest that a non-enzyme-mediated dimerization is the actual event by which paracaseolide A is produced in Nature.
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Affiliation(s)
- Tao Wang
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA
| | - Thomas R Hoye
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA
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Vasamsetty L, Sahu D, Ganguly B, Khan FA, Mehta G. Total synthesis of novel bioactive natural product paracaseolide A and analogues: computational evaluation of a ‘proposed’ biomimetic Diels–Alder reaction. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.09.072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Abstract
The concise total synthesis of aplykurodinone-1 with an unusual cis-fused hydrindane moiety has been accomplished without the need for any protecting group chemistry using a unique SmI2 mediated reductive cascade cyclization reaction and a direct cuprate mediated 1,4-addition. This work represents the first example of the use of a SmI2-mediated intramolecular cascade cyclization reaction between "halide, alkene and aldehyde" groups.
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Affiliation(s)
- Gang Liu
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School , Shenzhen 518055, China
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Boukouvalas J, Jean MA. Streamlined biomimetic synthesis of paracaseolide A via aerobic oxidation of a 2-silyloxyfuran. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.05.054] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Lee JS, Shin J, Shin HJ, Lee HS, Lee YJ, Lee HS, Won H. Total Synthesis and Configurational Validation of (+)-Violapyrone C. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402524] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
This review covers the literature published in 2012 for marine natural products, with 1035 citations (673 for the period January to December 2012) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1241 for 2012), together with the relevant biological activities, source organisms and country of origin. Biosynthetic studies, first syntheses, and syntheses that lead to the revision of structures or stereochemistries, have been included.
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Affiliation(s)
- John W Blunt
- Department of Chemistry, University of Canterbury, Christchurch, New Zealand.
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Hale KJ. Terpenoid- and shikimate-derived natural product total synthesis: a personal analysis and commentary on the importance of the papers that appear in this virtual issue. Org Lett 2014; 15:3181-98. [PMID: 23826672 DOI: 10.1021/ol401788y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Yin JP, Tang CL, Gao LX, Ma WP, Li JY, Li Y, Li J, Nan FJ. Design and synthesis of paracaseolide A analogues as selective protein tyrosine phosphatase 1B inhibitors. Org Biomol Chem 2014; 12:3441-5. [DOI: 10.1039/c4ob00214h] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Vasamsetty L, Khan FA, Mehta G. Total synthesis of a novel oxa-bowl natural product paracaseolide A via a ‘putative’ biomimetic pathway. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.04.097] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Affiliation(s)
- Tezcan Guney
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - George A. Kraus
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
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Giera DS, Stark CBW. Total synthesis of (±)-paracaseolide A and initial attempts at a Lewis acid mediated dimerization of its putative biosynthetic precursor. RSC Adv 2013. [DOI: 10.1039/c3ra44590a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Munoz A, Murelli RP. Acid-mediated coupling of γ-hydroxybutenolides and aldehydes: Synthesis of a new class of spirocyclic ketal-lactones. Tetrahedron Lett 2012; 53:6779-6781. [PMID: 23335822 DOI: 10.1016/j.tetlet.2012.09.139] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf), γ-methyl-γ-hydroxybutenolide reacts with aromatic aldehydes to generate a new class of stereochemically rich spirocyclic ketal-lactones in good yields and with excellent stereoselectivities. We believe that this process takes place through the in situ generation of protoanemonin followed by a Prins reaction. Herein, we describe this discovery, along with substrate scope and preliminary mechanistic studies.
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Affiliation(s)
- Alberto Munoz
- Department of Chemistry, Brooklyn College, The City University of New York, 2900 Bedford Avenue, Brooklyn, NY 11210
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