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Nakamura H, Bao M, Yamamoto Y. The Fate of Bis(η 3 -allyl)palladium Complexes in the Presence of Aldehydes (or Imines) and Allylic Chlorides: Stille Coupling versus Allylation of Aldehydes (or Imines). Angew Chem Int Ed Engl 2001; 40:3208-3210. [PMID: 29712062 DOI: 10.1002/1521-3773(20010903)40:17<3208::aid-anie3208>3.0.co;2-u] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2001] [Revised: 06/08/2001] [Indexed: 11/08/2022]
Abstract
The mere presence or absence of PPh3 suffices to control the reactivity of bis(η3 -allyl)palladium complexes. In the absence of PPh3 they undergo chemoselective allylic addition to aldehydes or imines, even in the presence of allylic chlorides, whereas in the presence of PPh3 the Stille coupling reaction takes place chemoselectively, even when aldehydes or imines are also present.
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24 |
85 |
2
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Chen XT, Zhou B, Bhattacharya SK, Gutteridge CE, Pettus TRR, Danishefsky SJ. The Total Synthesis of Eleutherobin: A Surprise Ending. Angew Chem Int Ed Engl 1998; 37:789-792. [PMID: 29711384 DOI: 10.1002/(sici)1521-3773(19980403)37:6<789::aid-anie789>3.0.co;2-3] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/1997] [Indexed: 11/07/2022]
Abstract
An "sp2 -sp3 Stille coupling" of the vinyl triflate 1 and the stannyl compound 2 is a key step toward the completion of the total synthesis of eleutherobin, a natural product exhibiting taxol-like cytotoxic activity.
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27 |
68 |
3
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Indole and Benzimidazole Bichalcophenes: Synthesis, DNA Binding and Antiparasitic Activity. Eur J Med Chem 2017; 143:1590-1596. [PMID: 29126729 PMCID: PMC5744864 DOI: 10.1016/j.ejmech.2017.10.056] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Revised: 10/13/2017] [Accepted: 10/18/2017] [Indexed: 11/20/2022]
Abstract
A novel series of indole and benzimidazole bichalcophene diamidine derivatives were prepared to study their antimicrobial activity against the tropical parasites causing African sleeping sickness and malaria. The dicyanoindoles needed to synthesize the target diamidines were obtained through Stille coupling reactions while the bis-cyanobenzimidazoles intermediates were made via condensation/cyclization reactions of different aldehydes with 4-cyano-1,2-diaminobenzene. Different amidine synthesis methodologies namely, lithium bis-trimethylsilylamide (LiN[Si(CH3)3]2) and Pinner methods were used to prepare the diamidines. Both types (indole and benzimidazole) derivatives of the new diamidines bind strongly with the DNA minor groove and generally show excellent in vitro antitrypanosomal activity. The diamidino-indole derivatives also showed excellent in vitro antimalarial activity while their benzimidazole counterparts were generally less active. Compound 7c was highly active in vivo and cured all mice infected with Trypanosoma brucei rhodesiense, a model that mimics the acute stage of African sleeping sickness, at a low dose of 4 × 5 mg/kg i.p. and hence 7c is more potent in vivo than pentamidine.
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Ghasimi S, Bretschneider SA, Huang W, Landfester K, Zhang KAI. A Conjugated Microporous Polymer for Palladium-Free, Visible Light-Promoted Photocatalytic Stille-Type Coupling Reactions. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2017; 4:1700101. [PMID: 28852627 PMCID: PMC5566346 DOI: 10.1002/advs.201700101] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/27/2017] [Indexed: 06/07/2023]
Abstract
The Stille coupling reaction is a versatile method to mainly form aromatic C-C bonds. However, up to now, the use of palladium catalysts is necessary. Here, a palladium-free and photocatalytic Stille-type coupling reaction of aryl iodides and aryl stannanes catalyzing a conjugated microporous polymer-based phototcatalyst under visible light irradiation at room temperature is reported. The novel coupling reaction mechanism occurs between the photogenerated aryl radical under oxidative destannylation of the aryl stannane, and the electron-activated aryl iodide, resulting into the aromatic C-C bond formation reaction. The visible light-promoted Stille-type coupling reaction using the polymer-based pure organic photocatalyst offers a simple, sustainable, and more economic synthetic pathway toward palladium-free aromatic C-C bond formation.
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35 |
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Ismail MA, Arafa RK, Youssef MM, El-Sayed WM. Anticancer, antioxidant activities, and DNA affinity of novel monocationic bithiophenes and analogues. Drug Des Devel Ther 2014; 8:1659-1672. [PMID: 25302019 PMCID: PMC4189708 DOI: 10.2147/dddt.s68016] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A series of 15 monocationic bithiophenes and isosteres were prepared and subjected to in vitro antiproliferative screening using the full National Cancer Institute (NCI)-60 cell line panel, representing nine types of cancer. Among the nine types of cancer involved in a five-dose screen, non-small cell lung and breast cancer cell lines were the most responsive to the antiproliferative effect of the tested compounds, especially cell lines A549/ATCC, NCI-H322M, and NCI-H460, whereas compounds 1a, 1c, 1d, and 7 exhibited potent activity, with GI50 values (drug concentration that causes 50% inhibition of cell growth) from less than 10 nM to 102 nM. In addition, compounds 1c and 1d gave GI50 values of 73 nM and 79 nM, respectively, against the MDA-MB-468 breast cancer cell line. Structure-activity relationship findings indicated that the mononitriles were far less active than their corresponding monoamidines and, within the amidines series, the bioisosteric replacement of a thiophene ring by a furan led to a reduction in antiproliferative activity. Also, molecular manipulations, involving substitution on the phenyl ring, or its replacement by a pyridyl, or alteration of the position of the amidine group, led to significant alteration in antiproliferative activity. On the other hand, DNA studies demonstrated that these monoamidine bichalcophenes have promising ability to cleave the genomic DNA. These monoamidines show a wide range of DNA affinities, as judged from their DNA cleavage effect, which are remarkably sensitive to all kinds of structural modifications. Finally, the novel bichalcophenes were tested for their antioxidant property by the ABTS (2,2'-azino- bis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt) assay, as well as lipid and nitric oxide scavenging techniques, and were found to exhibit good-to-potent antioxidant abilities.
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Low WK, Li J, Zhu M, Kommaraju SS, Shah-Mittal J, Hull K, Liu JO, Romo D. Second-generation derivatives of the eukaryotic translation initiation inhibitor pateamine A targeting eIF4A as potential anticancer agents. Bioorg Med Chem 2013; 22:116-25. [PMID: 24359706 DOI: 10.1016/j.bmc.2013.11.046] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 11/15/2013] [Accepted: 11/23/2013] [Indexed: 02/06/2023]
Abstract
A series of pateamine A (1) derivatives were synthesized for structure/activity relationship (SAR) studies and a selection of previous generation analogs were re-evaluated based on current information regarding the mechanism of action of these translation inhibitors. Structural modifications in the new generation of derivatives focused on alterations to the C19-C22 Z,E-diene and the trienyl side chain of the previously described simplified, des-methyl, des-amino pateamine A (DMDAPatA, 2). Derivatives were tested for anti-proliferative activity in cell culture and for inhibition of mammalian cap-dependent translation in vitro. Activity was highly dependent on the rigidity and conformation of the macrolide and the functionality of the side chain. The only well tolerated substitutions were replacement of the N,N-dimethyl amino group found on the side chain of 2 with other tertiary amine groups. SAR reported here suggests that this site may be modified in future studies to improve serum stability, cell-type specificity, and/or specificity towards rapidly proliferating cells.
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Research Support, Non-U.S. Gov't |
12 |
32 |
7
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Caló FP, Fürstner A. A Heteroleptic Dirhodium Catalyst for Asymmetric Cyclopropanation with α-Stannyl α-Diazoacetate. "Stereoretentive" Stille Coupling with Formation of Chiral Quarternary Carbon Centers. Angew Chem Int Ed Engl 2020; 59:13900-13907. [PMID: 32426901 PMCID: PMC7496581 DOI: 10.1002/anie.202004377] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/18/2020] [Indexed: 01/06/2023]
Abstract
The heteroleptic dirhodium paddlewheel catalyst 7 with a chiral carboxylate/acetamidate ligand sphere is uniquely effective in asymmetric [2+1] cycloadditions with α‐diazo‐α‐trimethylstannyl (silyl, germyl) acetate. Originally discovered as a trace impurity in a sample of the homoleptic parent complex [Rh2((R)‐TPCP)4] (5), it is shown that the protic acetamidate ligand is quintessential for rendering 7 highly enantioselective. The ‐NH group is thought to lock the ensuing metal carbene in place via interligand hydrogen bonding. The resulting stannylated cyclopropanes undergo “stereoretentive” cross coupling, which shows for the first time that even chiral quarternary carbon centers can be made by the Stille–Migita reaction.
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5 |
27 |
8
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Walker JR, Merit JE, Thomas-Tran R, Tang DTY, Du Bois J. Divergent Synthesis of Natural Derivatives of (+)-Saxitoxin Including 11-Saxitoxinethanoic Acid. Angew Chem Int Ed Engl 2019; 58:1689-1693. [PMID: 30488599 PMCID: PMC6426452 DOI: 10.1002/anie.201811717] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Indexed: 11/06/2022]
Abstract
The bis-guanidinium toxins are a collection of natural products that display nanomolar potency against select isoforms of eukaryotic voltage-gated Na+ ion channels. We describe a synthetic strategy that enables access to four of these poisons, namely 11-saxitoxinethanoic acid, C13-acetoxy saxitoxin, decarbamoyl saxitoxin, and saxitoxin. Highlights of this work include an unusual Mislow-Evans rearrangement and a late-stage Stille ketene acetal coupling. The IC50 value of 11-saxitoxinethanoic acid was measured against rat NaV 1.4, and found to be 17.0 nm, similar to those of the sulfated toxins gonyautoxin II and III.
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Research Support, N.I.H., Extramural |
6 |
22 |
9
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Heinrich M, Murphy JJ, Ilg MK, Letort A, Flasz J, Philipps P, Fürstner A. Total Synthesis of Putative Chagosensine. Angew Chem Int Ed Engl 2018; 57:13575-13581. [PMID: 30152031 DOI: 10.1002/anie.201808937] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Indexed: 12/22/2022]
Abstract
The marine macrolide chagosensine is the only natural product known to date that embodies a Z,Z-configured chloro-1,3-diene unit. This distinguishing substructure was prepared by a sequence of palladium-catalyzed 1,2-distannation of an alkyne precursor, regioselective Stille cross-coupling at the terminus of the resulting bisstannyl alkene with an elaborated alkenyl iodide, followed by chloro-destannation of the remaining internal site. The preparation of the required substrates centered on cobalt-catalyzed oxidative cyclization reactions of hydroxylated olefin precursors, which allowed the 2,5-trans-disubstituted tetrahydrofuran rings, embedded into each building block, to be formed with excellent selectivity. The highly strained macrolactone could ultimately be closed under forcing Yamaguchi conditions. Comparison of the spectral data of the synthetic sample with those of authentic chagosensine methyl ester confirmed that the structure of this intriguing compound has been mis-assigned by the isolation team.
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Research Support, Non-U.S. Gov't |
7 |
19 |
10
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Farahat AA, Kumar A, Say M, Wenzler T, Brun R, Paul A, Wilson WD, Boykin DW. Exploration of DAPI analogues: Synthesis, antitrypanosomal activity, DNA binding and fluorescence properties. Eur J Med Chem 2017; 128:70-78. [PMID: 28152428 PMCID: PMC5341734 DOI: 10.1016/j.ejmech.2017.01.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 01/17/2017] [Accepted: 01/23/2017] [Indexed: 02/05/2023]
Abstract
The DAPI structure has been modified by replacing the phenyl group with substituted phenyl or heteroaryl rings. Twelve amidines were synthesized and their DNA binding, fluorescence properties, in vitro and in vivo activities were evaluated. These compounds are shown to bind in the DNA minor groove with high affinity, and exhibit superior in vitro antitrypanosomal activity to that of DAPI. Six new diamidines (5b, 5c, 5d, 5e, 5f and 5j) exhibit superior in vivo activity to that of DAPI and four of these compounds provide 100% animal cure at a low dose of 4 × 5 mg/kg i.p. in T. b. rhodesiense infected mice. Generally, the fluorescence properties of the new analogues are inferior to that of DAPI with the exception of compound 5i which shows a moderate increase in efficacy while compound 5k is comparable to DAPI.
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11
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Holz J, Pfeffer C, Zuo H, Beierlein D, Richter G, Klemm E, Peters R. In Situ Generated Gold Nanoparticles on Active Carbon as Reusable Highly Efficient Catalysts for a C sp 3 -C sp 3 Stille Coupling. Angew Chem Int Ed Engl 2019; 58:10330-10334. [PMID: 31013549 DOI: 10.1002/anie.201902352] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 04/11/2019] [Indexed: 11/09/2022]
Abstract
Gold nanoparticle catalysts are important in many industrial production processes. Nevertheless, for traditional C sp 2 -C sp 2 cross-coupling reactions they have been rarely used and Pd catalysts usually give a superior performance. Herein we report that in situ formed gold metal nanoparticles are highly active catalysts for the cross coupling of allylstannanes and activated alkylbromides to form C sp 3 -C sp 3 bonds. Turnover numbers up to 29 000 could be achieved in the presence of active carbon as solid support, which allowed for convenient catalyst recovery and reuse. The present study is a rare case where a gold metal catalyst is superior to Pd catalysts in a cross-coupling reaction of an organic halide and an organometallic reagent.
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6 |
17 |
12
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Zhou J, Tan DX, Han FS. A Divergent Enantioselective Total Synthesis of Post-Iboga Indole Alkaloids. Angew Chem Int Ed Engl 2020; 59:18731-18740. [PMID: 32614122 DOI: 10.1002/anie.202008242] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Indexed: 11/05/2022]
Abstract
Divergent enantioselective total syntheses of five naturally occurring post-iboga indole alkaloids, dippinine B and C, 10,11-demethoxychippiine, 3-O-methyl-10,11-demethoxychippiine, and 3-hydroxy-3,4-secocoronaridine, as well as the two analogues 11-demethoxydippinine A and D, are presented for the first time. The enantioenriched aza[3.3.1]-bridged cycle, a common core intermediate to the target molecules, was constructed through an asymmetric phase-transfer-catalyzed Michael/aldol cascade reaction. The challenging azepane ring fused around the indole ring and the [3.3.1]-bridged cycle were installed through an intramolecular SN 2'-type reaction. These cyclization strategies enabled rapid construction of the [6.5.6.6.7]-pentacyclic core at an early stage. Highlights of the late-stage synthetic steps include a Pd-catalyzed Stille coupling and a highly stereoselective catalyst-controlled hydrogenation to incorporate the side chain at C20 with both R and S configurations in the natural products.
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13
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Ren S, Zhang W, Wang Z, Yassar A, Liao Z, Yi Z. Synergistic Use of All-Acceptor Strategies for the Preparation of an Organic Semiconductor and the Realization of High Electron Transport Properties in Organic Field-Effect Transistors. Polymers (Basel) 2023; 15:3392. [PMID: 37631449 PMCID: PMC10458505 DOI: 10.3390/polym15163392] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/10/2023] [Accepted: 08/11/2023] [Indexed: 08/27/2023] Open
Abstract
The development of n-type organic semiconductor materials for transporting electrons as part of logic circuits is equally important to the development of p-type materials for transporting holes. Currently, progress in research on n-type materials is relatively backward, and the number of polymers with high electron mobility is limited. As the core component of the organic field-effect transistor (OFET), the rational design and judicious selection of the structure of organic semiconductor materials are crucial to enhance the performance of devices. A novel conjugated copolymer with an all-acceptor structure was synthesized based on an effective chemical structure modification and design strategy. PDPPTT-2Tz was obtained by the Stille coupling of the DPPTT monomer with 2Tz-SnMe3, which features high molecular weight and thermal stability. The low-lying lowest unoccupied molecular orbital (LUMO) energy level of the copolymer was attributed to the introduction of electron-deficient bithiazole. DFT calculations revealed that this material is highly planar. The effect of modulation from a donor-acceptor to acceptor-acceptor structure on the improvement of electron mobility was significant, which showed a maximum value of 1.29 cm2 V-1 s-1 and an average value of 0.81 cm2 V-1 s-1 for electron mobility in BGBC-based OFET devices. Our results demonstrate that DPP-based polymers can be used not only as excellent p-type materials but also as promising n-type materials.
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14
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Ren S, Ding Y, Zhang W, Wang Z, Wang S, Yi Z. Rational Design of Novel Conjugated Terpolymers Based on Diketopyrrolopyrrole and Their Applications to Organic Thin-Film Transistors. Polymers (Basel) 2023; 15:3803. [PMID: 37765656 PMCID: PMC10535888 DOI: 10.3390/polym15183803] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/09/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023] Open
Abstract
Organic polymer semiconductor materials, due to their good chemical modifiability, can be easily tuned by rational molecular structure design to modulate their material properties, which, in turn, affects the device performance. Here, we designed and synthesized a series of materials based on terpolymer structures and applied them to organic thin-film transistor (OTFT) device applications. The four polymers, obtained by polymerization of three monomers relying on the Stille coupling reaction, shared comparable molecular weights, with the main structural difference being the ratio of the thiazole component to the fluorinated thiophene (Tz/FS). The conjugated polymers exhibited similar energy levels and thermal stability; however, their photochemical and crystalline properties were distinctly different, leading to significantly varied mobility behavior. Materials with a Tz/FS ratio of 50:50 showed the highest electron mobility, up to 0.69 cm2 V-1 s-1. Our investigation reveals the fundamental relationship between the structure and properties of materials and provides a basis for the design of semiconductor materials with higher carrier mobility.
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15
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Nişanci B, Dalkiliç E, Güney M, Daştan A. Synthesis and Diels-Alder cycloaddition reaction of norbornadiene and benzonorbornadiene dimers. Beilstein J Org Chem 2009; 5:39. [PMID: 19777139 PMCID: PMC2748719 DOI: 10.3762/bjoc.5.39] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Accepted: 08/07/2009] [Indexed: 11/23/2022] Open
Abstract
Dimeric forms of norbornadiene and benzonorbornadiene were synthesized starting with known monobromide derivatives. The Diels–Alder cycloaddition reaction of dimers with TCNE and PTAD was investigated and new norbornenoid polycyclics were obtained. All compounds were characterized properly using NMR spectroscopy.
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16 |
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16
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Senapati BK. Progress in the total synthesis of inthomycins. Beilstein J Org Chem 2021; 17:58-82. [PMID: 33488832 PMCID: PMC7801802 DOI: 10.3762/bjoc.17.7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/03/2020] [Indexed: 12/23/2022] Open
Abstract
The inthomycin family of antibiotics, isolated from Streptomyces strains, are interesting molecules for synthesis due to their characteristic common oxazole polyene chiral allylic β-hydroxycarbonyl fragments and significant biological activities. The full structural motif of the inthomycins is found in several more complex natural products including the oxazolomycins, 16-methyloxazolomycin, curromycins A and B, and KSM-2690. This review summarises the application of various efforts towards the synthesis of inthomycins and their analogues systematically.
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Review |
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17
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Bartels B, Cueni P, Muri D, Koerner M. Development of a safe and scalable route towards a tau PET tracer precursor. Bioorg Med Chem 2018; 26:970-976. [PMID: 29074348 DOI: 10.1016/j.bmc.2017.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/06/2017] [Accepted: 10/11/2017] [Indexed: 11/16/2022]
Abstract
A scalable 5-step synthesis of the diazacarbazole derivative 1 used as tau PET tracer precursor is reported. Key features of this synthesis include a Buchwald-Hartwig amination, a Pd catalyzed CH activation and a Suzuki-Miyaura cross-coupling.
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7 |
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18
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Hanson RN, McCaskill E, Hua E, Tongcharoensirikul P, Dilis R, Silver JL, Coulther TA, Ondrechen MJ, Labaree D, Hochberg RB. Synthesis of benzoylbenzamide derivatives of 17α-E-vinyl estradiol and evaluation as ligands for the estrogen receptor-α ligand binding domain. Steroids 2019; 144:15-20. [PMID: 30738075 DOI: 10.1016/j.steroids.2019.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/10/2019] [Accepted: 02/04/2019] [Indexed: 10/27/2022]
Abstract
A series consisting of substituted benzoylbenzamide derivatives of 17α-E-vinyl estradiol 6a-i and 7a-d was prepared in good overall yields from the corresponding novel iodinated benzoylbenzamide precursors using Pd(0)-catalyzed Stille coupling. Biological evaluation using competitive binding assays indicated that all compounds were effective ligands for the ERα- and ERβ-LBD (RBA = 0.5-10.0% of estradiol). Most of the compounds expressed lower stimulatory (agonist) potency (RSA <0.2-0.5%) compared to their binding affinity, however, the meta-substituted isomer 6h demonstrated a level of efficacy (RSA = 5.7%) comparable to its affinity (RBA = 9.5%). Docking studies of 6b, 6h, and 6i with the 2YAT crystal structure suggested that higher affinity and efficacy of 6h are due to an effective set of interactions with exposed receptor sidechains not observed with the ortho- and para- isomers. In this binding model, the terminal ring of the ligand is exposed to the solvent space, which would explain both the small variation in RBA values and the narrow SAR for the diverse structural features.
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Research Support, N.I.H., Extramural |
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1 |
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Shaya J, Correia G, Heinrich B, Ribierre JC, Polychronopoulou K, Mager L, Méry S. Functionalization of Biphenylcarbazole (CBP) with Siloxane-Hybrid Chains for Solvent-Free Liquid Materials. MOLECULES (BASEL, SWITZERLAND) 2021; 27:molecules27010089. [PMID: 35011322 PMCID: PMC8746609 DOI: 10.3390/molecules27010089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 12/06/2021] [Accepted: 12/08/2021] [Indexed: 11/09/2022]
Abstract
We report herein the synthesis of siloxane-functionalized CBP molecules (4,4′-bis(carbazole)-1,1′-biphenyl) for liquid optoelectronic applications. The room-temperature liquid state is obtained through a convenient functionalization of the molecules with heptamethyltrisiloxane chains via hydrosilylation of alkenyl spacers. The synthesis comprises screening of metal-catalyzed methodologies to introduce alkenyl linkers into carbazoles (Stille and Suzuki Miyaura cross-couplings), incorporate the alkenylcarbazoles to dihalobiphenyls (Ullmann coupling), and finally introduce the siloxane chains. The used conditions allowed the synthesis of the target compounds, despite the high reactivity of the alkenyl moieties bound to π-conjugated systems toward undesired side reactions such as polymerization, isomerization, and hydrogenation. The features of these solvent-free liquid CBP derivatives make them potentially interesting for fluidic optoelectronic applications.
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1 |
20
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Ren S, Wang Z, Zhang W, Ding Y, Yi Z. Donor-Acceptor-Based Organic Polymer Semiconductor Materials to Achieve High Hole Mobility in Organic Field-Effect Transistors. Polymers (Basel) 2023; 15:3713. [PMID: 37765568 PMCID: PMC10538171 DOI: 10.3390/polym15183713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 09/07/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023] Open
Abstract
Organic polymer semiconductor materials are conveniently tuned to energy levels because of their good chemically modifiable properties, thus enhancing their carrier transport capabilities. Here, we have designed and prepared a polymer with a donor-acceptor structure and tested its potential as a p-type material for organic field-effect transistor (OFET) applications using a solution-processing method. The conjugated polymers, obtained via the polymerization of the two monomers relying on the Stille coupling reaction, possess extremely high molecular weights and thermodynamic stability. Theoretical-based calculations show that PDPP-2S-Se has superior planarity, which is favorable for carrier transport within the main chain. Photophysical and electrochemical measurements systematically investigated the properties of the material and the energy levels with respect to the theoretical values. The maximum hole mobility of the PDPP-2S-Se-based OFET device is 0.59 cm2 V-1 s-1, which makes it a useful material for potential organic electronics applications.
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Chen J, Ding Y, Zhou J, Li N, Ren S, Zeng M. Preparation of Novel Organic Polymer Semiconductor and Its Properties in Transistors through Collaborative Theoretical and Experimental Approaches. Polymers (Basel) 2023; 15:4421. [PMID: 38006144 PMCID: PMC10674425 DOI: 10.3390/polym15224421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/14/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
Conjugated polymer semiconductors based on donor-acceptor structures are commonly employed as core materials for optoelectronic devices in the field of organic electronics. In this study, we designed and synthesized a novel acceptor unit thiophene-vinyl-diketopyrrolopyrrole, named TVDPP, based on a four-step organic synthesis procedure. Stille coupling reactions were applied with high yields of polymerization of TVDPP with fluorinated thiophene (FT) monomer. The molecular weight and thermal stability of the polymers were tested and showed high molecular weight and good thermal stability. Theoretical simulation calculations and 2D grazing-incidence wide-angle X-ray scattering (GIWAXS) tests verified the planarity of the material and excellent stacking properties, which are favorable for achieving high carrier mobility. Measurements based on the polymer as an organic thin film transistor (OTFT) device were carried out, and the mobility and on/off current ratio reached 0.383 cm2 V-1 s-1 and 104, respectively, showing its great potential in organic optoelectronics.
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Jing J, Hu Y, Tian Z, Wang Y, Yao L, Qiu L, Ackermann L, Karaghiosoff K, Li J. C-S-Selective Stille-Coupling Enables Stereodefined Alkene Synthesis. Angew Chem Int Ed Engl 2024; 63:e202408211. [PMID: 39076073 DOI: 10.1002/anie.202408211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 07/21/2024] [Accepted: 07/23/2024] [Indexed: 07/31/2024]
Abstract
A palladium-catalyzed highly C-S-selective Stille cross-coupling between aryl thianthrenium salts and tri- or tetrasubstituted alkenyl stannanes is described. Herein, critical challenges including site- and chemoselectivity control are well addressed through C-H thianthrenation and C-S alkenylation, thereby providing an expedient access to stereodefined tri- and tetrasubstituted alkenes in a stereoretentive fashion. Indeed, the palladium-catalyzed Stille-alkenylation of poly(pseudo)halogenated arenes displays privileged capability to differentiate C-S over C-I, C-Br, C-Cl bonds, as well as oxygen-based triflates (C-OTf), tosylates (C-OTs), carbamates and sulfamates under mild reaction conditions. Sequential and multiple cross-couplings via selective C-X functionalization should be widely applicable for increasing functional molecular complexity. Modular installation of stereospecific alkene motifs into pharmaceuticals illustrated the synthetic application of the present protocol in drug discovery.
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Farahat AA, Kumar A, Wenzler T, Brun R, Paul A, Guo P, Wilson WD, Boykin DW. Investigation of the effect of structure modification of furamidine on the DNA minor groove binding and antiprotozoal activity. Eur J Med Chem 2023; 252:115287. [PMID: 36958267 PMCID: PMC10127280 DOI: 10.1016/j.ejmech.2023.115287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/05/2023] [Accepted: 03/14/2023] [Indexed: 03/25/2023]
Abstract
New analogs of the antiprotozoal agent Furamidine were prepared utilizing Stille coupling reactions and amidation of the bisnitrile intermediate using lithium bis-trimethylsilylamide. Both the phenyl groups and the furan moiety of furamidine were replaced by heterocycles including thiophene, selenophene, indole or benzimidazole. Based upon the ΔTm and the CD results, the new compounds showed strong binding to the DNA minor groove. The new analogues are also more active both in vitro and in vivo than furamidine. Compounds 7a, 7b, and 7f showed the highest activity in vivo by curing 75% of animals, and this merits further evaluation.
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Yamanoi Y. Recent Progress on the Synthesis of Bipyridine Derivatives. Molecules 2024; 29:576. [PMID: 38338319 PMCID: PMC10856230 DOI: 10.3390/molecules29030576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 01/19/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024] Open
Abstract
Bipyridine and related compounds are starting materials or precursors for a variety of valuable substances such as biologically active molecules, ligands for catalysts, photosensitizers, viologens, and supramolecular architectures. Thus, it is important to classify their synthesis methods and understand their characteristics. Representative examples include methods using homo and heterocoupling of pyridine derivatives in the presence of a catalyst. Because bipyridine compounds strongly coordinate with metal centers, a decrease in catalytic activity and yield is often observed in the reaction system. To address this issue, this review provides insights into advances over the last ~30 years in bipyridine synthesis using metal complexes under both homogeneous and heterogeneous conditions. Moreover, strategies for bipyridine synthesis involving sulfur and phosphorous compounds are examined. These alternative pathways offer promising avenues for overcoming the challenges associated with traditional catalysis methods, providing a more comprehensive understanding of the synthesis landscape.
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