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Zachmann R, Yahata K, Holzheimer M, Jarret M, Wirtz C, Fürstner A. Total Syntheses of Nominal and Actual Prorocentin. J Am Chem Soc 2023; 145:2584-2595. [PMID: 36652728 PMCID: PMC9896551 DOI: 10.1021/jacs.2c12529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The dinoflagellate-derived polyether prorocentin is a co-metabolite of the archetypical serine/threonine phosphatase inhibitor okadaic acid. Whereas a structural relationship cannot be missed and a biosynthetic link was proposed, it is currently unknown whether there is any parallel in the bioactivity profile of these natural products. However, it was insinuated in the past that the structure assigned to prorocentin might need to be revised. Indeed, re-examination of the published spectra cast doubts as to the constitution of the fused/spirotricyclic BCD-ring system in the core. To clarify this issue, a flexible synthesis blueprint was devised that allowed us to obtain the originally proposed structure as well as the most plausible amended structure. The key to success was late-stage gold-catalyzed spirocyclization reactions that furnished the isomeric central segments with excellent selectivity. The lexicon of catalytic transformations used to make the required cyclization precursors comprised a titanium-mediated ester methylenation/metathesis cascade, a rare example of a gold-catalyzed allylic substitution, and chain extensions via organocatalytic asymmetric aldehyde propargylation. A wing sector to be attached to the isomeric cores was obtained by Krische allylation, followed by a superbly selective cobalt-catalyzed oxidative cyclization of the resulting di-unsaturated alcohol with the formation of a 2,5-trans-disubstituted tetrahydrofuran; the remaining terminal alkene was elaborated into an appropriate handle for fragment coupling by platinum-catalyzed asymmetric diboration/oxidation. The assembly of the different building blocks to the envisaged isomeric target compounds proved that the structure of prorocentin needs to be revised as disclosed herein.
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Peng R, VanNieuwenhze MS. Construction of the DEF–Benzoxocin Ring System of Nogalamycin and Menogaril via a Reductive Heck Cyclization. J Org Chem 2019; 84:173-180. [DOI: 10.1021/acs.joc.8b02575] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ruogu Peng
- Department of Chemistry, Indiana University-Bloomington 800 East Kirkwood Avenue, Bloomington, Indiana 47405-7102, United States
| | - Michael S. VanNieuwenhze
- Department of Chemistry, Indiana University-Bloomington 800 East Kirkwood Avenue, Bloomington, Indiana 47405-7102, United States
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3
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Oishi T. Design and Synthesis of Artificial Ladder-Shaped Polyethers for Exploring Biological Functions. HETEROCYCLES 2019. [DOI: 10.3987/rev-18-sr(f)1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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4
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HIRAMA M. Total synthesis and related studies of large, strained, and bioactive natural products. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2016; 92:290-329. [PMID: 27725470 PMCID: PMC5243947 DOI: 10.2183/pjab.92.290] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
Our chemical syntheses and related scientific investigations of natural products with complex architectures and powerful biological activities are described, focusing on the very large 3 nm-long polycyclic ethers called the ciguatoxins, highly strained and labile chromoprotein antitumor antibiotics featuring nine-membered enediyne cores, and extremely potent anthelmintic macrolides called the avermectins.
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Affiliation(s)
- Masahiro HIRAMA
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, Miyagi, Japan
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5
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Takamura H, Wada H, Ogino M, Kikuchi T, Kadota I, Uemura D. Stereodivergent Synthesis and Relative Stereostructure of the C1–C13 Fragment of Symbiodinolide. J Org Chem 2015; 80:3111-23. [DOI: 10.1021/acs.joc.5b00027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hiroyoshi Takamura
- Department
of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Hiroko Wada
- Department
of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Mao Ogino
- Department
of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Takahiro Kikuchi
- Department
of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Isao Kadota
- Department
of Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Daisuke Uemura
- Department
of Chemistry, Faculty of Science, Kanagawa University, 2946 Tsuchiya, Hiratsuka 259-1293, Japan
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Meng FY, Huang SL, Liu YH, Hu Z, Lai G, Luh TY. Stereoselective Formation of Eight-Membered Rings by Radical Cyclization of Silylenedioxy-Tethered Bis-methacrylate Derivatives. J Org Chem 2015; 80:2869-73. [DOI: 10.1021/jo502947k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fan-Yi Meng
- Key
Laboratory of Organosilicon Chemistry and Technology, Hangzhou Normal University, Hangzhou, Zhejiang 310036, China
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106
| | - Shou-Ling Huang
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106
| | - Yi-Hung Liu
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106
| | - Ziqiang Hu
- Key
Laboratory of Organosilicon Chemistry and Technology, Hangzhou Normal University, Hangzhou, Zhejiang 310036, China
| | - Guoqiao Lai
- Key
Laboratory of Organosilicon Chemistry and Technology, Hangzhou Normal University, Hangzhou, Zhejiang 310036, China
| | - Tien-Yau Luh
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan 106
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Yamashita S, Takeuchi K, Koyama T, Inoue M, Hayashi Y, Hirama M. Practical route to the left wing of CTX1B and total syntheses of CTX1B and 54-deoxyCTX1B. Chemistry 2014; 21:2621-8. [PMID: 25529606 DOI: 10.1002/chem.201405629] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Indexed: 11/07/2022]
Abstract
Ciguatoxins, the principal causative agents of ciguatera seafood poisoning, are extremely large polycyclic ethers. We report herein a reliable route for constructing the left wing of CTX1B, which possesses the acid/base/oxidant-sensitive bisallylic ether moiety, by a 6-exo radical cyclization/ring-closing metathesis strategy. This new route enabled us to achieve the second-generation total synthesis of CTX1B and the first synthesis of 54-deoxyCTX1B.
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Affiliation(s)
- Shuji Yamashita
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan).
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8
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Mousseau JJ, Morten CJ, Jamison TF. A dioxane template for highly selective epoxy alcohol cyclizations. Chemistry 2013; 19:10004-16. [PMID: 23775936 PMCID: PMC3763493 DOI: 10.1002/chem.201300845] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Indexed: 11/06/2022]
Abstract
Ladder polyether natural products are a class of natural products denoted by their high functional-group density and large number of well-defined stereocenters. They comprise the toxic component of harmful algal blooms (HABs), having significant negative economic and environmental ramifications. However, their mode of action, namely blocking various cellular ion channels, also denotes their promise as potential anticancer agents. Understanding their potential mode of biosynthesis will not only help with developing ways to limit the damage of HABs, but would also facilitate the synthesis of a range of analogs with interesting biological activity. 1,3-Dioxan-5-ol substrates display remarkable 'enhanced template effects' in water-promoted epoxide cyclization processes en route to the synthesis of these ladder polyether natural products. In many cases, they provide near complete endo-to-exo selectivity in the cyclization of epoxy alcohols, thereby strongly favoring the formation of tetrahydropyran (THP) over tetrahydrofuran (THF) rings. The effects of various Brønsted and Lewis acidic and basic conditions are explored to demonstrate the superior selectivity of the template over the previously reported THP-based epoxy alcohols. In addition, the consideration of other synthetic routes are also considered with the goal of gaining rapid access to a plethora of potential starting materials applicable towards the synthesis of ladder polyethers. Finally, cascade sequences with polyepoxides are investigated, further demonstrating the versatility of this new reaction template.
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Affiliation(s)
- James J. Mousseau
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA
| | - Christopher J. Morten
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA
| | - Timothy F. Jamison
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA
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Yamashita S, Ishihara Y, Morita H, Uchiyama J, Takeuchi K, Inoue M, Hirama M. Stereoselective 6-exo radical cyclization using cis-vinyl sulfoxide: practical total synthesis of CTX3C. JOURNAL OF NATURAL PRODUCTS 2011; 74:357-364. [PMID: 21250701 DOI: 10.1021/np100729d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Ciguatoxins, the principal causative toxins of ciguatera seafood poisoning, are large ladder-like polycyclic ethers. We report a highly stereoselective 6-exo radical cyclization/ring-closing olefin metathesis sequence to construct the syn/trans-fused polyether system. The new method was applied to the practical synthesis of ciguatoxin CTX3C.
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Affiliation(s)
- Shuji Yamashita
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
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11
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Kobayashi S, Hori M, Hirama M. Synthesis of trans-fused tetrahydrooxepins: stereoselective allylation of sulfur or fluoro-substituted tetrahydrooxepins. Carbohydr Res 2007; 343:443-52. [PMID: 18068694 DOI: 10.1016/j.carres.2007.11.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Accepted: 11/15/2007] [Indexed: 10/22/2022]
Abstract
An efficient route to the trans-fused tetrahydrooxepin corresponding to the E ring of ciguatoxin was developed. Wide screening of allylation reactions of sulfur or fluoro-substituted tetrahydrooxepin revealed that the optimum method for obtaining the beta-allylation product selectively was the use of a combination of allyltrimethylsilane and TiCl(4) with 6-fluoro-7-hydroxytetrahydrooxepin.
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Affiliation(s)
- Shoji Kobayashi
- Department of Chemistry, Graduate School of Science, Osaka Prefecture University, Sakai 599-8531, Japan.
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Inoue M, Miyazaki K, Ishihara Y, Tatami A, Ohnuma Y, Kawada Y, Komano K, Yamashita S, Lee N, Hirama M. Total synthesis of ciguatoxin and 51-hydroxyCTX3C. J Am Chem Soc 2007; 128:9352-4. [PMID: 16848469 DOI: 10.1021/ja063041p] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ciguatoxins, the principal causative toxins of ciguatera seafood poisoning, are large ladder-like polycyclic ethers with the 13 ether rings ranging from five- to nine-membered. In this paper, we describe the total synthesis of the two most toxic members of the ciguatoxin family, ciguatoxin 1 and 51-hydroxyCTX3C 2, based on a unified synthetic strategy. The key features in our syntheses were (i) direct construction of the O,S-acetal from the corresponding left and right wing fragments (3, 4, 14); (ii) stereo- and chemoselective radical reaction of the alpha-oxyradical with pentafluorophenyl acrylate to achieve cyclization of the seven-membered G-ring; (iii) ring-closing metathesis reaction to build the nine-membered F-ring; and (iv) an efficient protective group strategy using the oxidatively removable 2-naphthylmethyl groups.
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Affiliation(s)
- Masayuki Inoue
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
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14
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Torikai K, Yari H, Mori M, Ujihara S, Matsumori N, Murata M, Oishi T. Design and synthesis of an artificial ladder-shaped polyether that interacts with glycophorin A. Bioorg Med Chem Lett 2006; 16:6355-9. [PMID: 16989999 DOI: 10.1016/j.bmcl.2006.09.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2006] [Revised: 08/31/2006] [Accepted: 09/02/2006] [Indexed: 10/24/2022]
Abstract
Ladder-shaped polyether (LSP) compounds, such as brevetoxins and ciguatoxins, are thought to interact with transmembrane (TM) proteins. As a model LSP compound, we designed and synthesized an artificial tetracyclic ether (1) and evaluated its interaction with glycophorin A (GpA), a membrane protein known to dimerize or oligomerize between membrane-integral alpha-helical domains. Model compound 1 was found to induce the dissociation of oligomeric GpA in a similar manner to natural LSPs when examined by SDS-PAGE. The results suggest that even an artificial tetracyclic ether possesses the ability to interact with TM proteins, presumably through the intermolecular hydrogen bonds (C(alpha)-Hcdots, three dots, centeredO) with the GXXXG motif.
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Affiliation(s)
- Kohei Torikai
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
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Inoue M, Ishihara Y, Yamashita S, Hirama M. Convergent Assembly of Polycyclic Ethers via Acyl Radical Addition to Unactivated Enol Ether. Org Lett 2006; 8:5801-4. [PMID: 17134276 DOI: 10.1021/ol062349i] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new convergent strategy for assembling 6/6- and 6/7-fused ether ring systems was developed. The key features in our method include Ag+-promoted facile formation of chemically labile enol ether from O,S-acetal and addition of an acyl radical to unactivated enol ether to cyclize a six- or seven-membered ether ring. [reaction: see text]
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Affiliation(s)
- Masayuki Inoue
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
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Takizawa A, Fujiwara K, Doi E, Murai A, Kawai H, Suzuki T. Convergent synthesis of the common FGHI-ring part of ciguatoxins. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.05.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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18
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Affiliation(s)
- Masayuki Inoue
- Department of Chemistry and Research and Analytical Center for Giant Molecules, Graduate School of Science, Tohoku University, Sendai, Japan.
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Hirama M. Total synthesis of ciguatoxin CTX3C: a venture into the problems of ciguatera seafood poisoning. CHEM REC 2005; 5:240-50. [PMID: 16059875 DOI: 10.1002/tcr.20049] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
After a twelve-year struggle, the total synthesis of ciguatoxin CTX3C has been achieved. Annually, more than 20,000 people worldwide suffer from ciguatera seafood poisoning. The extremely small amounts of the causative neurotoxin, ciguatoxin, in fish hampered the isolation, structural elucidation, detailed biological study, and preparation of anti-ciguatoxin antibodies for detecting these toxins. The large (3 nanometers long) and complicated molecular structure of ciguatoxins hindered chemists from completing a total synthesis. The chemical synthesis of CTX3C, determination of the absolute configuration, and synthesis-based preparation of the monoclonal antibodies as well as the effect of synthetic CTX3C on voltage-sensitive sodium channels are outlined.
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Affiliation(s)
- Masahiro Hirama
- Department of Chemistry, Graduate School of Science, Tohoku University, and SORST, Japan Science and Technology Corporation (JST), Sendai 980-8578, Japan.
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Watanabe K, Suzuki M, Murata M, Oishi T. Convergent synthesis of the FGHI ring system of yessotoxin: stereoselective construction of the G ring. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.04.040] [Citation(s) in RCA: 33] [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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Herndon JW. The chemistry of the carbon-transition metal double and triple bond: annual survey covering the year 2003. Coord Chem Rev 2005. [DOI: 10.1016/j.ccr.2004.10.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
More than 20 000 people suffer annually from ciguatera seafood poisoning in subtropical and tropical regions. The extremely low content of the causative neurotoxins, designated as ciguatoxins, in fish has hampered their isolation, detailed biological study, and preparation of anti-ciguatoxin antibodies for detecting these toxins. Ciguatoxins consist of 12 trans-fused polycyclic ethers, ranging from six- to nine-membered, and include a spirally attached five-membered cyclic ether at one end. The large (3 nm in length) and complicated molecular structure of ciguatoxins has impeded chemists from completing their total synthesis. In 2001, we achieved the first total synthesis of ciguatoxin CTX3C by assembly of four structural fragments. Since then, protocols to combine the fragments have significantly improved in terms of overall stereoselectivity, efficiency, and practicality. In this Account, we describe recently evolved methodologies for the total synthesis of CTX3C.
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Affiliation(s)
- Masayuki Inoue
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
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Inoue M, Miyazaki K, Uehara H, Maruyama M, Hirama M. First- and second-generation total synthesis of ciguatoxin CTX3C. Proc Natl Acad Sci U S A 2004; 101:12013-8. [PMID: 15199182 PMCID: PMC514426 DOI: 10.1073/pnas.0401684101] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2004] [Accepted: 05/13/2004] [Indexed: 11/18/2022] Open
Abstract
More than 20,000 people suffer annually from ciguatera seafood poisoning in subtropical and tropical regions. The extremely low content of the causative neurotoxins, designated as ciguatoxins, in fish has hampered isolation, detailed biological studies, and preparation of anti-ciguatoxin antibodies for detecting these toxins. Furthermore, the large (3 nm in length) and complex molecular structure of ciguatoxins has impeded chemists from completing their total synthesis. In this article, the full details of studies leading to the total synthesis of ciguatoxin CTX3C are provided. The key elements of the first-generation approach include O,O-acetal formation from the right and left wing fragments, conversion from O,O-acetal to O,S-acetal, a radical reaction to cyclize the G ring, a ring-closing metathesis reaction to close the F ring, and final removal of the 2-naphtylmethyl protective groups. Subsequent studies provided a second-generation total synthesis, which is more concise and results in a higher yield. Second-generation synthesis was accomplished by using a direct method of constructing the key intermediate O,S-acetal from alpha-chlorosulfide and a secondary alcohol. These syntheses ensure a practical supply of ciguatoxin for biological applications.
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Affiliation(s)
- Masayuki Inoue
- Department of Chemistry, Graduate School of Science, Tohoku University and Solution Oriented Research for Science and Technology, Japan Science and Technology Agency, Sendai 980-8578, Japan
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A new synthesis of key intermediates for the assembly of polycyclic ethers: Yb(OTf)3-promoted formation of O,S-acetals from α-fluorosulfides and alcohols. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.01.077] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Kobayashi S, Alizadeh BH, Sasaki SY, Oguri H, Hirama M. Synthesis of the Fully Functionalized ABCDE Ring Moiety of Ciguatoxin. Org Lett 2004; 6:751-4. [PMID: 14986966 DOI: 10.1021/ol0364475] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A fully functionalized ABCDE ring moiety of ciguatoxin (CTX), the major causative agent of ciguatera poisoning, was synthesized for the first time. The present strategy involves the efficient installation of the C5-dihydroxybutenyl substituent and construction of the tetrahydrooxepin E ring using a novel alpha-chlorosulfide synthon. [structure: see text]
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Affiliation(s)
- Shoji Kobayashi
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
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Oishi T, Watanabe K, Murata M. Convergent synthesis of trans-fused 6/n/6/6 (n=7, 8) tetracyclic ether system via α-cyano ethers. Tetrahedron Lett 2003. [DOI: 10.1016/s0040-4039(03)01862-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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