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Yang JS, Lu K, Li CX, Zhao ZH, Zhang XM, Zhang FM, Tu YQ. Chiral 1,2,3-Triazolium Salt Catalyzed Asymmetric Mono- and Dialkylation of 2,5-Diketopiperazines with the Construction of Tetrasubstituted Carbon Centers. Angew Chem Int Ed Engl 2022; 61:e202114129. [PMID: 34981881 DOI: 10.1002/anie.202114129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Indexed: 11/07/2022]
Abstract
Novel asymmetric mono- and dialkylation reactions of α-substituted 2,5-diketopiperazines catalyzed by new chiral spirocyclic-amide-derived triazolium organocatalysts have been developed, resulting in a range of enantioenriched 2,5-diketopiperazine derivatives containing one or two tetrasubstituted carbon stereocenters. The reactions feature high yields (up to 98%), and excellent cis-diastereo- and enantioselectivities (up to >20:1 dr, >99 % ee), and they provide a new asymmetric synthetic approach to important functionalized 2,5-diketopiperazine skeletons. Furthermore, a possible reaction mechanism was proposed based on both control experiments and extensive DFT calculations.
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Affiliation(s)
- Ju-Song Yang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Ka Lu
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Chen-Xiao Li
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Zu-Hang Zhao
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Xiao-Ming Zhang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Fu-Min Zhang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Yong-Qiang Tu
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China.,School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
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2
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Yang J, Lu K, Li C, Zhao Z, Zhang X, Zhang F, Tu Y. Chiral 1,2,3‐Triazolium Salt Catalyzed Asymmetric Mono‐ and Dialkylation of 2,5‐Diketopiperazines with the Construction of Tetrasubstituted Carbon Centers. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114129] [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)
- Ju‐Song Yang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
| | - Ka Lu
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
| | - Chen‐Xiao Li
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
| | - Zu‐Hang Zhao
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
| | - Xiao‐Ming Zhang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
| | - Fu‐Min Zhang
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
| | - Yong‐Qiang Tu
- State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China
- School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University Shanghai 200240 P. R. China
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Ge Y, Han Z, Wang Z, Ding K. Ir-Catalyzed Double Asymmetric Hydrogenation of 3,6-Dialkylidene-2,5-diketopiperazines for Enantioselective Synthesis of Cyclic Dipeptides. J Am Chem Soc 2019; 141:8981-8988. [PMID: 31079460 DOI: 10.1021/jacs.9b02920] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
An Ir/spiro[4,4]-1,6-nonadiene-based phosphine-oxazoline ligand (SpinPHOX) complex-catalyzed double asymmetric hydrogenation of 3,6-dialkylidene-1,4-dimethylpiperazine-2,5-diones has been developed, providing efficient and practical access to a wide variety of chiral 3,6-disubstituted-2,5-diketopiperazines in high yields with exclusive cis-diastereo- and excellent enantioselectivities (>99% de, up to 98% ee). The synthetic utilities of the protocol have been demonstrated in a gram scale synthesis of 6a and efficient construction of chiral products 8, 14, and 17 as well as a 2-butenyl-bridged bicyclic diketopiperazine 10 and hydroxydiketopiperazine 11. With an analogous achiral Ir catalyst, the hydrogenation of enantiopure monohydrogenated intermediate 7a gave cis-6a as the only product, indicating that the second-step hydrogenation of the titled transformation is a chiral substrate controlled process. The reaction profile study for asymmetric hydrogenation (AH) of 5a revealed that the concentration of the monohydrogenation intermediate 7a remained at a low level (<8%) during the course of hydrogenation. The hydrogenation of 5a to 6a proceeded significantly faster than that of its half-hydrogenated intermediate ( S)-7a, indicating that the titled reaction involves primarily a processive mechanism, in which a single catalyst molecule performs consecutive hydrogenation of the two C═C double bonds in substrate 5a without dissociation of the partially reduced 7a. The present protocol represents a rare example of asymmetric catalytic consecutive hydrogenation of heterocycles and provides an alternative way for efficient construction of cyclic dipeptides.
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Affiliation(s)
- Yao Ge
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Zhaobin Han
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China
| | - Zheng Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China
| | - Kuiling Ding
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China.,Collaborative Innovation Center of Chemical Science and Engineering , Nankai University , Tianjin 300071 , China
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5
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Klas KR, Kato H, Frisvad JC, Yu F, Newmister SA, Fraley AE, Sherman DH, Tsukamoto S, Williams RM. Structural and stereochemical diversity in prenylated indole alkaloids containing the bicyclo[2.2.2]diazaoctane ring system from marine and terrestrial fungi. Nat Prod Rep 2019; 35:532-558. [PMID: 29632911 DOI: 10.1039/c7np00042a] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Covering: up to February 2017 Various fungi of the genera Aspergillus, Penicillium, and Malbranchea produce prenylated indole alkaloids possessing a bicyclo[2.2.2]diazaoctane ring system. After the discovery of distinct enantiomers of the natural alkaloids stephacidin A and notoamide B, from A. protuberus MF297-2 and A. amoenus NRRL 35660, another fungi, A. taichungensis, was found to produce their diastereomers, 6-epi-stephacidin A and versicolamide B, as major metabolites. Distinct enantiomers of stephacidin A and 6-epi-stephacidin A may be derived from a common precursor, notoamide S, by enzymes that form a bicyclo[2.2.2]diazaoctane core via a putative intramolecular hetero-Diels-Alder cycloaddition. This review provides our current understanding of the structural and stereochemical homologies and disparities of these alkaloids. Through the deployment of biomimetic syntheses, whole-genome sequencing, and biochemical studies, a unified biogenesis of both the dioxopiperazine and the monooxopiperazine families of prenylated indole alkaloids constituted of bicyclo[2.2.2]diazaoctane ring systems is presented.
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Affiliation(s)
- Kimberly R Klas
- Department of Chemistry, Colorado State University, 1301 Center Avenue, Fort Collins, CO 80523, USA.
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Acosta Quintero LM, Palma A, Cobo J, Glidewell C. A versatile synthesis of cyclic dipeptides using the stepwise construction of the piperazine-2,5-dione ring from simple precursors: synthetic sequence and the structure of a representative product, (3RS)-4-(2-allyl-3,5-dimethylphenyl)-1-benzyl-3-phenylpiperazine-2,5-dione. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2018; 74:159-165. [DOI: 10.1107/s2053229618000037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Accepted: 01/02/2018] [Indexed: 11/10/2022]
Abstract
A versatile synthesis of multiply substituted cyclic dipeptides has been designed, based on the stepwise construction of the piperazine-2,5-dione ring using molecular fragments from four different precursor molecules. Starting from substituted 2-allylanilines, reaction with methyl 2-bromo-2-phenylacetate yields the corresponding methyl 2-(2-allylanilino)-2-phenylacetates, which react with haloacetyl chlorides to give methyl 2-[N-(2-allylphenyl)-2-haloacetamido]-2-phenylacetates, which then undergo ring closure with benzylamine to yield the corresponding cyclic dipeptides of type 4-(2-allylphenyl)-1-benzyl-3-phenylpiperazine-2,5-dione. (3RS)-4-(2-Allyl-3,5-dimethylphenyl)-1-benzyl-3-phenylpiperazine-2,5-dione, C28H28N2O2, (IIId), crystallizes with Z′ = 2 in the space group P21/c; the allyl groups in the two independent molecules adopt different conformations and, in one of them, the allyl group is disordered over two sets of atomic sites having occupancies of 0.534 (4) and 0.466 (4). In both molecules, the piperazine-2,5-dione ring adopts a boat conformation, with the 3-phenyl ring in a quasi-axial site. The molecules of (IIId) are linked into a three-dimensional framework structure by a combination of three C—H...O hydrogen bonds and three C—H...π(arene) hydrogen bonds. Comparisons are made with some related structures.
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Amatov T, Gebauer M, Pohl R, Cisařová I, Jahn U. Oxidative radical cyclizations of diketopiperazines bearing an amidomalonate unit. Heterointermediate reaction sequences toward the asperparalines and stephacidins. Free Radic Res 2016; 50:S6-S17. [PMID: 27806645 DOI: 10.1080/10715762.2016.1223295] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A novel approach to the diazabicyclo[2.2.2]octane core of prenylated bridged diketopiperazine alkaloids is described by direct oxidative cyclizations of functionalized diketopiperazines mediated by ferrocenium hexafluorophosphate or the Mn(OAc)3•2H2O/Cu(OTf)2 system. Divergent reaction pathways take place depending on the substitution pattern of the substrates and the oxidation conditions such as temperature or the presence or absence of persistent radical TEMPO. For ester-substituted diketopiperazines, the ester group exerts a significant influence on the reaction outcome and stereochemistry of the radical cyclizations.
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Affiliation(s)
- Tynchtyk Amatov
- a Institute of Organic Chemistry and Biochemistry , Czech Academy of Sciences , Flemingovo namesti 2 , Prague 6, Czech Republic
| | - Martin Gebauer
- a Institute of Organic Chemistry and Biochemistry , Czech Academy of Sciences , Flemingovo namesti 2 , Prague 6, Czech Republic
| | - Radek Pohl
- a Institute of Organic Chemistry and Biochemistry , Czech Academy of Sciences , Flemingovo namesti 2 , Prague 6, Czech Republic
| | - Ivana Cisařová
- b Department of Inorganic Chemistry, Faculty of Science , Charles University in Prague , Hlavova 2030/8 , Prague 2, Czech Republic
| | - Ullrich Jahn
- a Institute of Organic Chemistry and Biochemistry , Czech Academy of Sciences , Flemingovo namesti 2 , Prague 6, Czech Republic
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Kamauchi H, Kinoshita K, Sugita T, Koyama K. Conditional changes enhanced production of bioactive metabolites of marine derived fungus Eurotium rubrum. Bioorg Med Chem Lett 2016; 26:4911-4914. [PMID: 27641468 DOI: 10.1016/j.bmcl.2016.09.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 09/02/2016] [Accepted: 09/06/2016] [Indexed: 11/20/2022]
Abstract
Metabolites of marine derived fungus Eurotium rubrum MPUC136 differed between cultivation on wheat medium and Czapek-Dox agar medium. Melanin synthesis inhibitory activity of crude extract of culture on wheat medium showed stronger activity than that of crude extract of culture on Czapek-Dox agar medium. A new diketopiperazine compound isoechinulin D (1) and eight reported diketopiperazines (2-9) were isolated from the crude extract of wheat medium. The structure of 1 was established using NMR, MS and IR methods. 2-5 inhibited melanogenesis using B16 melanoma cells (IC50=68, 2.4, 83, 9.1μM each). Structure-Activity-Relationships of diketopiperazines (1-10) indicated the importance of the prenyl groups at C-2, C-5 and C-7, the vinyl group at C-12 to C-25 and the sp2 carbons at C-8 and C-9. Isolated compounds (1-9) were not or slightly observed from the extracts of Czapek-Dox agar medium by HPLC analysis, suggesting that different cultivation processes could affect metabolism and enhance bioactivities.
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Affiliation(s)
- Hitoshi Kamauchi
- Department of Pharmacognosy and Phytochemistry, Meiji Pharmaceutical University, Noshio 2-522-1, Kiyose-shi, Tokyo 204-8588, Japan
| | - Kaoru Kinoshita
- Department of Pharmacognosy and Phytochemistry, Meiji Pharmaceutical University, Noshio 2-522-1, Kiyose-shi, Tokyo 204-8588, Japan
| | - Takashi Sugita
- Department of Microbiology, Meiji Pharmaceutical University, Noshio 2-522-1, Kiyose-shi, Tokyo 204-8588, Japan
| | - Kiyotaka Koyama
- Department of Pharmacognosy and Phytochemistry, Meiji Pharmaceutical University, Noshio 2-522-1, Kiyose-shi, Tokyo 204-8588, Japan.
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10
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Zhong S, Wandler AEE, Schepers U, Nieger M, Bräse S. Synthesis of New Diketopiperazines, Thiolation to Thiodiketopiperazines, and Examination of Their ROS-Generating Properties. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500900] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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11
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Amatov T, Pohl R, Císařová I, Jahn U. Synthesis of Bridged Diketopiperazines by Using the Persistent Radical Effect and a Formal Synthesis of Bicyclomycin. Angew Chem Int Ed Engl 2015; 54:12153-7. [DOI: 10.1002/anie.201504883] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Indexed: 01/29/2023]
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12
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Amatov T, Pohl R, Císařová I, Jahn U. Synthese überbrückter Diketopiperazine mit Hilfe des persistenten Radikaleffekts und eine formale Synthese von Bicyclomycin. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201504883] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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13
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Cabanillas A, Davies CD, Male L, Simpkins NS. Highly enantioselective access to diketopiperazines via cinchona alkaloid catalyzed Michael additions. Chem Sci 2014; 6:1350-1354. [PMID: 29560222 PMCID: PMC5811140 DOI: 10.1039/c4sc03218g] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 11/26/2014] [Indexed: 12/14/2022] Open
Abstract
Alkaloid catalysed additions to triketopiperazines gives products in high yield and er (88 : 12 to 99 : 1), including bridged hydroxy-DKPs via Michael-addition–ring closure.
Michael addition reactions of triketopiperazine (TKP) derivatives to enones, mediated by a cinchona alkaloid-derived catalyst, deliver products in high yield and enantiomeric ratio (er). Use of unsaturated ester, nitrile or sulfone partners gives bridged hydroxy-diketopiperazine (DKP) products resulting from a novel Michael addition–ring closure.
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Affiliation(s)
- Alejandro Cabanillas
- School of Chemistry , University of Birmingham , Edgbaston , Birmingham , B15 2TT UK
| | | | - Louise Male
- School of Chemistry , University of Birmingham , Edgbaston , Birmingham , B15 2TT UK
| | - Nigel S Simpkins
- School of Chemistry , University of Birmingham , Edgbaston , Birmingham , B15 2TT UK
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Simpkins NS, Pavlakos I, Weller MD, Male L. The cascade radical cyclisation approach to prenylated alkaloids: synthesis of stephacidin A and notoamide B. Org Biomol Chem 2013; 11:4957-70. [PMID: 23797367 DOI: 10.1039/c3ob40979a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A strategy for the synthesis of members of the prenylated indole alkaloid family is described, which involves a radical cascade process of an appropriately substituted diketopiperazine (DKP) core structure. Several approaches to the generation of the initial radical were explored, with the most successful involving treatment of a sulfenyl substituted DKP under classical reductive conditions by heating with Bu3SnH and a radical initiator. The required, fully substituted, radical precursor DKP structures were prepared using regio- and stereocontrolled enolate chemistry of simpler proline-tryptophan derived DKPs. The new approach allowed rapid access to a key polycyclic indoline structure, which was converted into either of the natural products stephacidin A or notoamide B.
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Affiliation(s)
- Nigel S Simpkins
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
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Borthwick AD. 2,5-Diketopiperazines: synthesis, reactions, medicinal chemistry, and bioactive natural products. Chem Rev 2012; 112:3641-716. [PMID: 22575049 DOI: 10.1021/cr200398y] [Citation(s) in RCA: 606] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Monbaliu JCM, Hansen FK, Beagle LK, Panzner MJ, Steel PJ, Todadze E, Stevens CV, Katritzky AR. A New Benzotriazole-Mediated Stereoflexible Gateway to Hetero-2,5-diketopiperazines. Chemistry 2012; 18:2632-8. [DOI: 10.1002/chem.201103143] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Indexed: 11/08/2022]
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Simpkins N, Pavlakos I, Male L. Rapid access to polycyclic indolines related to the stephacidin alkaloids using a radical cascade. Chem Commun (Camb) 2012; 48:1958-60. [DOI: 10.1039/c1cc16510k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Crick PJ, Simpkins NS, Highton A. Synthesis of the Asperparaline Core by a Radical Cascade. Org Lett 2011; 13:6472-5. [DOI: 10.1021/ol202769f] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Peter J. Crick
- School of Chemistry, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, U.K., and AstraZeneca R&D Charnwood, Loughborough, LE11 5RH, U.K
| | - Nigel S. Simpkins
- School of Chemistry, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, U.K., and AstraZeneca R&D Charnwood, Loughborough, LE11 5RH, U.K
| | - Adrian Highton
- School of Chemistry, The University of Birmingham, Edgbaston, Birmingham, B15 2TT, U.K., and AstraZeneca R&D Charnwood, Loughborough, LE11 5RH, U.K
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Frebault FC, Simpkins NS. A cationic cyclisation route to prenylated indole alkaloids: synthesis of malbrancheamide B and brevianamide B, and progress towards stephacidin A. Tetrahedron 2010. [DOI: 10.1016/j.tet.2010.04.093] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Affiliation(s)
- Tanja Gaich
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, 92037 La Jolla, California
| | - Phil S. Baran
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, 92037 La Jolla, California
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Miller KA, Williams RM. Synthetic approaches to the bicyclo[2.2.2]diazaoctane ring system common to the paraherquamides, stephacidins and related prenylated indole alkaloids. Chem Soc Rev 2009; 38:3160-74. [PMID: 19847349 PMCID: PMC2839869 DOI: 10.1039/b816705m] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The bicyclo[2.2.2]diazaoctane ring system is common to a number of highly biologically active secondary metabolites isolated from numerous species of fungi. In this tutorial review, we describe the varied synthetic approaches that have been employed to construct this ring system in the course of recent total synthesis endeavors, and this review should be of interest to synthetic organic chemists and natural product chemists. Detailed herein are a number of synthetic disconnections including intramolecular S(N)2' cyclizations, biomimetic Diels-Alder reactions, radical cyclizations, and cationic cascade reactions.
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Affiliation(s)
- Kenneth A Miller
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523-1872, USA
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Frebault F, Simpkins NS, Fenwick A. Concise enantioselective synthesis of ent-malbrancheamide B. J Am Chem Soc 2009; 131:4214-5. [PMID: 19317498 DOI: 10.1021/ja900688y] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A concise enantioselective synthesis of the fungal metabolite ent-malbrancheamide B was accomplished through the union of a C-prenylated proline derivative and a substituted indole pyruvic acid SEM enol ether, followed by a cationic double cyclization as the key step.
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Affiliation(s)
- Frederic Frebault
- School of Chemistry, The University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Campo VL, Martins MB, da Silva CH, Carvalho I. Novel and facile solution-phase synthesis of 2,5-diketopiperazines and O-glycosylated analogs. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.04.069] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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25
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Jainta M, Nieger M, Bräse S. Microwave-Assisted Stereoselective One-Pot Synthesis of Symmetrical and Unsymmetrical 2,5-Diketopiperazines from Unprotected Amino Acids. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800605] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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