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Lim H, Seong S, Kim Y, Seo S, Han S. Biopatterned Reorganization of Alkaloids Enabled by Ring-Opening Functionalization of Tertiary Amines. J Am Chem Soc 2021; 143:19966-19974. [PMID: 34784466 DOI: 10.1021/jacs.1c10205] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Biosynthetic processes often involve reorganization of one family of natural products to another. Chemical emulation of nature's rearrangement-based structural diversification strategy would enable the conversion of readily available natural products to other value-added secondary metabolites. However, the development of a chemical method that can be universally applied to structurally diverse natural products is nontrivial. Key to the successful reorganization of complex molecules is a versatile and mild bond-cleaving method that correctly places desired functionality, facilitating the target synthesis. Here, we report a ring-opening functionalization of a tertiary amine that can introduce desired functionalities in the context of alkaloids reorganization. The semistability of the difluoromethylated ammonium salt, accessed by the reaction of tertiary amine and in situ generated difluorocarbene, enabled the attack at the α-position by various external nucleophiles. The utility and generality of the method is highlighted by its applications in the transformation of securinega, iboga, and sarpagine alkaloids to neosecurinega, chippiine/dippinine, and vobasine-type bisindole alkaloids, respectively. During the course of these biosynthetically inspired reorganizations, we could explore chemical reactivities of biogenetically relevant precursors.
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Affiliation(s)
- Hyeonggeun Lim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Sikwang Seong
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Youyoung Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Sangwon Seo
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Sunkyu Han
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
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Banerjee A, Panda G. Total synthesis of selected bioactive alkaloids, their structure–function relationships and molecular target interactions: A comparative synthetic analysis of tryptophan originated chiral pool approaches vs other synthons. RESULTS IN CHEMISTRY 2021. [DOI: 10.1016/j.rechem.2021.100215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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3
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Dagoneau D, Wang Q, Zhu J. Towards the Sarpagine-Ajmaline-Macroline Family of Indole Alkaloids: Enantioselective Synthesis of an N-Demethyl Alstolactone Diastereomer. Chemistry 2020; 26:4866-4873. [PMID: 32065430 DOI: 10.1002/chem.202000415] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/14/2020] [Indexed: 12/19/2022]
Abstract
the strategy involving the use of functionalized tetrahydro-6H-cycloocta[b]indol-6-one is reported as a key intermediate for synthesis of members of the sarpagine-ajmaline-macroline family of monoterpene indole alkaloids. The desired tricycle was synthesized through the following key steps: 1) Evans' syn-selective aldolization; 2) Liebeskind-Srogl cross-coupling using the phenylthiol ester of 3-chloropropanoic acid as a surrogate of acrylic thioester for the synthesis of 2,3-disubstituted indoles; and 3) ring-closing metathesis (RCM) for the formation of the eight-membered ring. An N-allylation followed by intramolecular 1,4-addition was planned for synthesis of the vobasine class of natural products. However, attempted cyclizations under a diverse set of conditions involving anionic, radical, and organopalladium/organonickel species failed to produce the bridged ring system. On the other hand, esterification of the pendant primary alcohol function with acetoacetic acid, followed by intramolecular Michael addition, afforded the desired tetracycle with excellent diastereoselectivity. Subsequent functional group manipulation and transannular cyclization of the amino alcohol afforded the N(1)-demethyl-3,5-diepi-alstolactone. We believe that the same synthetic route would afford the alstolactone should the amino alcohol with appropriate stereochemistry be used as the starting material.
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Affiliation(s)
- Dylan Dagoneau
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland
| | - Qian Wang
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland
| | - Jieping Zhu
- Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland
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4
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Stephen MR, Rahman MT, Tiruveedhula VVNPB, Fonseca GO, Deschamps JR, Cook JM. Concise Total Synthesis of (-)-Affinisine Oxindole, (+)-Isoalstonisine, (+)-Alstofoline, (-)-Macrogentine, (+)-N a -Demethylalstonisine, (-)-Alstonoxine A, and (+)-Alstonisine. Chemistry 2017; 23:15805-15819. [PMID: 28875520 PMCID: PMC6168078 DOI: 10.1002/chem.201703572] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Indexed: 11/05/2022]
Abstract
A highly enantio- and diastereoselective strategy to access any member of the sarpagine/macroline family of oxindole alkaloids via internal asymmetric induction was developed from readily available d-(+)-tryptophan. At the center of this approach was the diastereospecific generation of the spiro[pyrrolidine-3,3'-oxindole] moiety at an early stage via a tert-butyl hypochlorite-promoted oxidative rearrangement of a chiral tetrahydro-β-carboline derivative. This key branching point determined the spatial configuration at the C-7 spiro center to be entirely 7R or 7S. Other key stereospecific processes were the asymmetric Pictet-Spengler reaction and Dieckmann cyclization, which were scalable to the 600 and 150 gram levels, respectively. Execution of this approach resulted in first enantiospecific total synthesis of (+)-isoalstonisine and (-)-macrogentine from the chitosenine series (7R), as well as (+)-alstonisine, (+)-alstofoline, (-)-alstonoxine A and (+)-Na -demethylalstonisine from the alstonisine series (7S).
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Affiliation(s)
- Michael Rajesh Stephen
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin, 53211, USA
| | - M Toufiqur Rahman
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin, 53211, USA
| | - V V N Phani Babu Tiruveedhula
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin, 53211, USA
| | - German O Fonseca
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin, 53211, USA
| | - Jeffrey R Deschamps
- Center for Biomolecular Science and Engineering, Naval Research Laboratory, Code 6930, Washington, DC, 20375, USA
| | - James M Cook
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin, 53211, USA
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Suh YG, Lim C, Sim J, Lee JK, Surh YJ, Paek SM. Construction of the Azacyclic Core of Tabernaemontanine-Related Alkaloids via Tandem Reformatsky-Aza-Claisen Rearrangement. J Org Chem 2017; 82:1464-1470. [PMID: 28051867 DOI: 10.1021/acs.joc.6b02648] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A divergent synthetic methodology for a tabernaemontanine-related alkaloid was developed. The synthetic route features practical improvements in the Pictet-Spengler cyclization for the tetrahydro-β-carboline intermediate and an unprecedented tandem Reformatsky-aza-Claisen rearrangement to create the core carbon skeleton and stereochemistries of tabernaemontanine-related alkaloids.
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Affiliation(s)
- Young-Ger Suh
- College of Pharmacy, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea
| | - Changjin Lim
- College of Pharmacy, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea
| | - Jaehoon Sim
- College of Pharmacy, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea
| | - Jae Kyun Lee
- Neuro-Medicine Center, Korea Institute of Science and Technology , P.O. Box 131, Seoul 130-650, Republic of Korea
| | - Young-Joon Surh
- Tumor Microenvironment Global Core Research Center, College of Pharmacy, Seoul National University , 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea
| | - Seung-Mann Paek
- College of Pharmacy, Research Institute of Pharmaceutical Science, Gyeongsang National University , Jinju daero, Jinju 660-751, Republic of Korea
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Synthesis of Bisindole Alkaloids from the Apocynaceae Which Contain a Macroline or Sarpagine Unit: A Review. Molecules 2016; 21:molecules21111525. [PMID: 27854259 PMCID: PMC5214337 DOI: 10.3390/molecules21111525] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 10/30/2016] [Accepted: 11/04/2016] [Indexed: 11/28/2022] Open
Abstract
Bisindole natural products consist of two monomeric indole alkaloid units as their obligate constituents. Bisindoles are more potent with respect to their biological activity than their corresponding monomeric units. In addition, the synthesis of bisindoles are far more challenging than the synthesis of monomeric indole alkaloids. Herein is reviewed the enantiospecific total and partial synthesis of bisindole alkaloids isolated primarily from the Alstonia genus of the Apocynaceae family. The monomeric units belong to the sarpagine, ajmaline, macroline, vobasine, and pleiocarpamine series. An up-to-date discussion of their isolation, characterization, biological activity as well as approaches to their partial and total synthesis by means of both synthetic and biosynthetic strategies are presented.
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Abstract
The sarpagine-related macroline and ajmaline alkaloids share a common biosynthetic origin, and bear important structural similarities, as expected. These indole alkaloids are widely dispersed in 25 plant genera, principally in the family Apocynaceae. Very diverse and interesting biological properties have been reported for this group of natural products. Isolation of new sarpagine-related alkaloids and the asymmetric synthesis of these structurally complex molecules are of paramount importance to the synthetic and medicinal chemists. A total of 115 newly isolated sarpagine-related macroline and ajmaline alkaloids, along with their physicochemical properties have been included in this chapter. A general and efficient strategy for the synthesis of these monomeric alkaloids, as well as bisindoles, has been presented, which involves application of the asymmetric Pictet-Spengler reaction (>98% ee) as a key step because of the ease of scale up of the tetracyclic template. Also included in this chapter are the syntheses of the sarpagine-related alkaloids, published since 2000.
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Affiliation(s)
- Ojas A. Namjoshi
- RTI International, Center for Drug Design and Discovery, 3040 E. Cornwallis Road, Research Triangle Park, NC 27709, USA
| | - James M. Cook
- University of Wisconsin-Milwaukee, Chemistry Department, 3210 E. Cramer Street, Milwaukee, WI 53211, USA
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Fonseca GO, Wang ZJ, Namjoshi OA, Deschamps JR, Cook JM. First stereospecific total synthesis of (−)-affinisine oxindole as well as facile entry into the C(7)-diastereomeric chitosenine stereochemistry. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2014.11.036] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Rallapalli SK, Namjoshi OA, Tiruveedhula VVNPB, Deschamps JR, Cook JM. Stereospecific total synthesis of the indole alkaloid ervincidine. Establishment of the C-6 hydroxyl stereochemistry. J Org Chem 2014; 79:3776-80. [PMID: 24697213 PMCID: PMC4017614 DOI: 10.1021/jo402692u] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
The
total synthesis of the indole alkaloid ervincidine (3) is reported. This research provides a general entry into C-6 hydroxy-substituted
indole alkaloids with either an α or a β configuration.
This study corrects the errors in Glasby’s book (GlasbyJ. S.Encyclopedia of the Alkaloids; Plenum Press: New York, 1975) and Lounasmaa et al.’s review
(LounasmaaM.; HanhinenP.; WestersundM. In The Alkaloids; CordellG. A., Ed.; Academic Press: San Diego, CA, 1999; Vol. 52, pp 103–195) as well as clarifies the work
of Yunusov et al. (MalikovV. M.; SharipovM. R.; YunusovS. Yu.Khim. Prir. Soedin.1972, 8, 760−761. RakhimovD. A.; SharipovM. R.; AripovKh. N.; MalikovV. M.; ShakirovT. T.; YunusovS. Yu.Khim. Prir. Soedin.1970, 6, 724–725). It establishes the correct absolute configuration
of the C-6 hydroxyl function in ervincidine. This serves as a structure
proof and corrects the misassigned structure reported in the literature.
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Affiliation(s)
- Sundari K Rallapalli
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin 53201, United States
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Edwankar CR, Edwankar RV, Namjoshi OA, Liao X, Cook JM. Stereospecific approach to the synthesis of ring-A oxygenated sarpagine indole alkaloids. Total synthesis of the dimeric indole alkaloid P-(+)-dispegatrine and six other monomeric indole alkaloids. J Org Chem 2013; 78:6471-87. [PMID: 23721107 PMCID: PMC3722876 DOI: 10.1021/jo400469t] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first regio- and stereocontrolled total synthesis of the bisphenolic, bisquaternary alkaloid (+)-dispegatrine (1) has been accomplished in an overall yield of 8.3% (12 reaction vessels) from 5-methoxy-d-tryptophan ethyl ester (17). A crucial late-stage thallium(III) mediated intermolecular oxidative dehydrodimerization was employed in the formation of the C9-C9' biaryl axis in 1. The complete stereocontrol observed in this key biaryl coupling step is due to the asymmetric induction by the natural sarpagine configuration of the monomer lochnerine (6) and was confirmed by both the Suzuki and the oxidative dehydrodimerization model studies on the tetrahydro β-carboline (35). The axial chirality of the lochnerine dimer (40) and in turn dispegatrine (1) was established by X-ray crystallography and was determined to be P(S). Additionally, the first total synthesis of the monomeric indole alkaloids (+)-spegatrine (2), (+)-10-methoxyvellosimine (5), (+)-lochnerine (6), lochvinerine (7), (+)-sarpagine (8), and (+)-lochneram (11) were also achieved via the common pentacyclic intermediate 16.
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Affiliation(s)
- Chitra R. Edwankar
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - Rahul V. Edwankar
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - Ojas A. Namjoshi
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - Xuebin Liao
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - James M. Cook
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
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Kajjout M, Smietana M, Leroy J, Rolando C. A new approach to the synthesis of (Z)-2-fluoro-2-alkenals via Wittig-type carbonyl condensation reactions of 2-(fluoromethyl)-4,4,6-trimethyl-1,3-oxazine phosphonium bromide. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.01.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Ankner T, Cosner CC, Helquist P. Palladium- and nickel-catalyzed alkenylation of enolates. Chemistry 2013; 19:1858-71. [PMID: 23325616 DOI: 10.1002/chem.201202798] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Transition-metal-catalyzed alkenylation of enolates provides a direct method to synthesize broadly useful β,γ-unsaturated carbonyl compounds from the corresponding carbonyl compound and alkenyl halides. Despite being reported in the early seventies, this reaction class saw little development for many years. In the past decade, however, efforts to develop this reaction further have increased considerably, and many research groups have reported efficient coupling protocols, including enantioselective versions. These reactions most commonly employ palladium catalysts, but there are also some important reports using nickel. There are many examples of this powerful transformation being used in the synthesis of complex natural products.
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Affiliation(s)
- Tobias Ankner
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden
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Ishikura M, Abe T, Choshi T, Hibino S. Simple indole alkaloids and those with a non-rearranged monoterpenoid unit. Nat Prod Rep 2013; 30:694-752. [DOI: 10.1039/c3np20118j] [Citation(s) in RCA: 269] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Zemmouri R, Kajjout M, Castanet Y, Eddarir S, Rolando C. Palladium-catalyzed stereoconvergent formylation of (E/Z)-β-bromo-β-fluorostyrenes: straightforward access to (Z)-α-fluorocinnamic aldehydes and (Z)-β-fluorocinnamic alcohols. J Org Chem 2011; 76:7691-8. [PMID: 21812490 DOI: 10.1021/jo200798h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report here the stereoconvergent formylation of (E/Z)-β-bromo-β-fluorostyrene mixtures with carbon monoxide and sodium formate catalyzed by palladium. Optimization of reaction conditions leads to the corresponding pure (Z)-α-fluorocinnamaldehydes in good yields. The reaction was extended to styrenes bearing electro-attracting or electro-donating groups. The obtained α-fluoroaldehydes were smoothly reduced to the corresponding (Z)-β-fluorocinnamic alcohol by NaBH(4). The reaction could be performed on functionalized substrates as demonstrated by the access to the glucoside of β-fluoroconiferyl alcohol, (Z)-β-fluoroconiferin, a strong inhibitor of lignin polymerization.
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Affiliation(s)
- Rajae Zemmouri
- USR CNRS 3290, Miniaturisation pour la Synthèse, l'Analyse et la Protéomique, Université de Lille 1, Sciences et Technologies, 59655 Villeneuve d’Ascq, France
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Yin W, Kabir MS, Wang Z, Rallapalli SK, Ma J, Cook JM. Enantiospecific total synthesis of the important biogenetic intermediates along the ajmaline pathway, (+)-polyneuridine and (+)-polyneuridine aldehyde, as well as 16-epivellosimine and macusine A. J Org Chem 2010; 75:3339-49. [PMID: 20392128 DOI: 10.1021/jo100279w] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first stereospecific synthesis of polyneuridine aldehyde (6), 16-epivellosimine (7), (+)-polyneuridine (8), and (+)-macusine A (9) has been accomplished from commercially available d-(+)-tryptophan methyl ester. d-(+)-Tryptophan has served here both as the chiral auxiliary and the starting material for the synthesis of the common intermediate, (+)-vellosimine (13). This alkaloid was available in enantiospecific fashion in seven reaction vessels in 27% overall yield from d-(+)-trytophan methyl ester (14) via a combination of the asymmetric Pictet-Spengler reaction, Dieckmann cyclization, and a stereocontrolled intramolecular enolate-driven palladium-mediated cross-coupling reaction. A new process for this stereocontrolled intramolecular cross-coupling has been developed via a copper-mediated process. The initial results of this investigation indicated that an enolate-driven palladium-mediated cross-coupling reaction can be accomplished by a copper-mediated process which is less expensive and much easier to work up. An enantiospecific total synthesis of (+)-polyneuridine aldehyde (6), which has been proposed as an important biogenetic intermediate in the biosynthesis of quebrachidine (2), was then accomplished in an overall yield of 14.1% in 13 reaction vessels from d-(+)-tryptophan methyl ester (14). Aldehyde 13 was protected as the N(a)-Boc aldehyde 32 and then converted into the prochiral C(16)-quaternary diol 12 via the practical Tollens' reaction and deprotection. The DDQ-mediated oxidative cyclization and TFA/Et(3)SiH reductive cleavage served as protection/deprotection steps to provide a versatile entry into the three alkaloids polyneuridine aldehyde (6), polyneuridine (8), and macusine A (9) from the quarternary diol 12. The oxidation of the 16-hydroxymethyl group present in the axial position was achieved with the Corey-Kim reagent to provide the desired beta-axial aldehydes, polyneuridine aldehyde (6), and 16-epivellosimine (7) with 100% diastereoselectivity.
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Affiliation(s)
- Wenyuan Yin
- Department of Chemistry & Biochemistry, University of Wisconsin-Milwaukee, 3210 North Cramer Street, Milwaukee, Wisconsin 53211, USA
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