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Search for "13C" in Full Text gives 2000 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Synthesis, biological and electrochemical evaluation of glycidyl esters of phosphorus acids as potential anticancer drugs

  • Almaz A. Zagidullin,
  • Emil R. Bulatov,
  • Mikhail N. Khrizanforov,
  • Damir R. Davletshin,
  • Elvina M. Gilyazova,
  • Ivan A. Strelkov and
  • Vasily A. Miluykov

Beilstein J. Org. Chem. 2025, 21, 1909–1916, doi:10.3762/bjoc.21.148

Graphical Abstract
  • , 13C 100.6 MHz). 1H and 13C NMR data are reported with reference to solvent resonances, and 31P NMR spectra were reported with respect to external 85% H3PO4 (0 ppm). All experiments were carried out using standard Bruker pulse programs. Infrared (IR) spectra were recorded on a Bruker Vector-22
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Published 15 Sep 2025

Stereoselective electrochemical intramolecular imino-pinacol reaction: a straightforward entry to enantiopure piperazines

  • Margherita Gazzotti,
  • Fabrizio Medici,
  • Valerio Chiroli,
  • Laura Raimondi,
  • Sergio Rossi and
  • Maurizio Benaglia

Beilstein J. Org. Chem. 2025, 21, 1897–1908, doi:10.3762/bjoc.21.147

Graphical Abstract
  • procedures and physical data for the new compounds, copies of 1H and 13C NMR spectra of the prepared compounds. Acknowledgements The authors thank Prof. A. Puglisi (Università degli Studi di Milano) for valuable discussions. For the single-crystal X-ray diffraction analysis the Unitech COSPECT (Università
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Published 12 Sep 2025

Preparation of spirocyclic oxindoles by cyclisation of an oxime to a nitrone and dipolar cycloaddition

  • Beth L. Ritchie,
  • Alexandra Longcake and
  • Iain Coldham

Beilstein J. Org. Chem. 2025, 21, 1890–1896, doi:10.3762/bjoc.21.146

Graphical Abstract
  • ) are quoted to the nearest 0.5 Hz with values in hertz (Hz). 13C NMR spectra were recorded on the above instrument at 100 MHz. Low- and high-resolution (accurate mass) mass spectra were recorded on a Walters LCT instrument using electrospray ionisation (ESI). Synthesis of the aldehyde 4 Sc(OTf)3 (0.63
  • Hz, 1H), 7.02 (td, J = 7.5, 1.0 Hz, 1H), 6.86 (d, J = 7.5 Hz, 1H), 4.27 (d, J = 9.5 Hz, 1H), 3.97 (d, J = 9.5 Hz, 1H), 3.23 (s, 3H), 3.17 (dd, J = 18.0, 1.0 Hz, 1H), 2.99 (dd, J = 18.0. 1.0 Hz, 1H), 2.44 (s, 3H); 13C NMR (101 MHz, CDCl3) δ 196.7, 174.9, 145.0, 143.6, 132.0, 129.8, 129.0, 127.8, 127.6
  • ), 4.25 (ddd, J = 11.0, 6.5, 1.5 Hz, 1H), 3.86 (d, J = 15.0 Hz, 1H) 3.70 (dd, J = 7.5, 1.5 Hz, 1H), 3.42 (d, J = 15.0 Hz, 1H), 3.22 (s, 3H), 3.08 (s, 3H), 2.55 (dd, J = 13.0, 11.0 Hz, 1H), 2.24 (dd, J = 13.0, 6.5 Hz, 1H); 13C NMR (101 MHz, CDCl3) δ 178.4, 175.2, 174.8, 142.9, 134.2, 128.8, 123.4, 122.3
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Published 11 Sep 2025

Fe-catalyzed efficient synthesis of 2,4- and 4-substituted quinolines via C(sp2)–C(sp2) bond scission of styrenes

  • Prafull A. Jagtap,
  • Manish M. Petkar,
  • Vaishnavi R. Sawant and
  • Bhalchandra M. Bhanage

Beilstein J. Org. Chem. 2025, 21, 1799–1807, doi:10.3762/bjoc.21.142

Graphical Abstract
  • -disubstituted quinolone 3a along with 36% of 4-substituted quinolone 3a′ were observed during GC and GC–MS analysis, and the structures of both quinoline moieties were identified by 1H and 13C NMR spectroscopy. Encouraged by this result, we next examined the feasibility of the reaction with methanol as solvent
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Published 05 Sep 2025

Synthesis of chiral cyclohexane-linked bisimidazolines

  • Changmeng Xi,
  • Qingshan Sun and
  • Jiaxi Xu

Beilstein J. Org. Chem. 2025, 21, 1786–1790, doi:10.3762/bjoc.21.140

Graphical Abstract
  • of chiral cyclohexane-linked bisimidazoline ligands. Supporting Information Supporting Information File 20: Analytical data and copies of 1H and 13C NMR spectra of compounds 2 and 4, copies of HRMS spectra of unknown compounds 4 and 5. Funding This research was supported by the National Key R & D
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Published 04 Sep 2025

Unique halogen–π association detected in single crystals of C–N atropisomeric N-(2-halophenyl)quinolin-2-one derivatives and the thione analogue

  • Mai Uchibori,
  • Nanami Murate,
  • Kanako Shima,
  • Tatsunori Sakagami,
  • Ko Kanehisa,
  • Gary James Richards,
  • Akiko Hori and
  • Osamu Kitagawa

Beilstein J. Org. Chem. 2025, 21, 1748–1756, doi:10.3762/bjoc.21.138

Graphical Abstract
  • their spectral data, copies of 1H and 13C{1H} NMR charts of compounds 1–4, chiral MPLC and HPLC chart in compounds 1a,b, 2a, evaluation of rotational barriers of compounds 1a,b, and X-ray crystal data of rac-1a,b, (P)-1a,b, rac-2a (check CIF). Funding This work was partly supported by JSPS KAKENHI (C
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Published 01 Sep 2025

Convenient alternative synthesis of the Malassezia-derived virulence factor malassezione and related compounds

  • Karu Ramesh and
  • Stephen L. Bearne

Beilstein J. Org. Chem. 2025, 21, 1730–1736, doi:10.3762/bjoc.21.135

Graphical Abstract
  • proton (1H) spectra are reported relative to the residual solvent signal for CDCl3 (δ 7.26) or methanol-d4 (δ 3.31) [30]. Chemical shifts (δ in ppm) for carbon (13C) spectra are reported relative to the residual solvent signal for CDCl3 (δ 77.16) or methanol-d4 (δ 49.00) [30]. Abbreviations used for
  • 53 °C [28]); 1H NMR (400 MHz, CDCl3) δ 8.17 (d, J = 8.1 Hz, 1H, ArH), 7.58 (s, 1H, ArH), 7.54 (dt, J = 7.7 and 1.1 Hz, 1H, ArH), 7.34 (ddd, J = 8.4, 7.2 and 1.1 Hz, 1H, ArH), 7.26 (ddd, J = 8.4, 7.2 and 1.1 Hz, 1H, ArH), 3.73 (d, J = 1.1 Hz, 2H), 3.71 (s, 3H, CH3), 1.67 (s, 9H, 3 × CH3) ppm; 13C NMR
  • , 7.2 and 1.3 Hz, 1H, ArH), 3.76 (s, J = 1.0 Hz, 2H), 1.66 (s, 9H, 3 × CH3) ppm; 13C NMR (100 MHz, CDCl3) δ 176.8, 149.7, 135.5, 135.0, 124.84, 124.80, 122.8, 119.1, 115.5, 112.5, 83.9, 30.9, 28.3 ppm; HRESIMS (m/z): [M + Na]+ calcd for C15H17NNaO4, 298.1050; found, 298.1057. These spectroscopic data
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Published 28 Aug 2025

Structural analysis of stereoselective galactose pyruvylation toward the synthesis of bacterial capsular polysaccharides

  • Tsun-Yi Chiang,
  • Mei-Huei Lin,
  • Chun-Wei Chang,
  • Jinq-Chyi Lee and
  • Cheng-Chung Wang

Beilstein J. Org. Chem. 2025, 21, 1671–1677, doi:10.3762/bjoc.21.131

Graphical Abstract
  • define the stereochemistry of pyruvate ketals as either R- or S-configurations. Typically, S-configuration exhibits 13C NMR shifts between δ 17–24 ppm and 1H NMR shifts δ 1.60–2.10 ppm, whereas the R-configuration shows 13C shifts downfield at δ 24-27 ppm and 1H shifts at δ 1.40–2.00 ppm [19][20][21][22
  • (4) was treated with methyl pyruvate in acetonitrile (Table 1, entry 1) to produce pyruvylated galactose 5. The use of polar solvents such as acetonitrile promotes the formation of the more thermodynamically favorable diastereomer [21][28][29]. For the property of the R-isomer of 5, the 13C NMR
  • 1H-13C HSQC NMR analysis was performed to further characterize the structure of 14 (see Supporting Information File 1). 1H NMR coupling constants revealed the presence of one α-glycosidic bond at C1′ (δ 5.49, J = 4.3 Hz) and two β-glycosidic bonds at C1 (δ 4.22, bs) and C1′′ (δ 5.56, J = 3.8 Hz). The
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Published 21 Aug 2025

Formal synthesis of a selective estrogen receptor modulator with tetrahydrofluorenone structure using [3 + 2 + 1] cycloaddition of yne-vinylcyclopropanes and CO

  • Jing Zhang,
  • Guanyu Zhang,
  • Hongxi Bai and
  • Zhi-Xiang Yu

Beilstein J. Org. Chem. 2025, 21, 1639–1644, doi:10.3762/bjoc.21.127

Graphical Abstract
  • synthesis of 1. Formal synthesis of SERMs molecule VI. Supporting Information Supporting Information File 54: Experimental procedures, product characterizations, and copies of the 1H and 13C NMR spectra. Acknowledgements We thank Zhiqiang Huang for testing the stoichiometric Heck reaction in this
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Published 14 Aug 2025

Synthesis of optically active folded cyclic dimers and trimers

  • Ena Kumamoto,
  • Kana Ogawa,
  • Kazunori Okamoto and
  • Yasuhiro Morisaki

Beilstein J. Org. Chem. 2025, 21, 1603–1612, doi:10.3762/bjoc.21.124

Graphical Abstract
  • and twisted, which caused the different chiroptical properties. Experimental General 1H and 13C NMR spectra were recorded on a JEOL JNM ECZ-500R instrument at 500 and 125 MHz, respectively. Samples were analyzed in CDCl3, and the chemical shift values were expressed relative to Me4Si as an internal
  • %) as a light yellow solid. Rf = 0.73 (CHCl3/hexane = 1:2 v/v); 1H NMR (CDCl3, 500 MHz) δ 1.20 (s, 42H), 2.97–3.08 (m, 4H), 3.49–3.53 (m, 4H), 7.06 (s, 2H), 7.21 (s, 2H), 7.37–7.40 (m, 4H), 7.60–7.62 (m, 2H), 7.70–7.73 (m, 2H) ppm; 13C NMR (CDCl3, 125 MHz) δ 11.48, 18.84, 32.32, 32.57, 92.38, 93.65
  • (m, 2H) ppm; 13C NMR (CDCl3, 125 MHz) δ 32.31, 32.43, 81.96, 83.04, 92.45, 93.34, 93.94, 124.30, 125.18, 125.98, 126.02, 128.25, 128.37, 132.22, 133.29, 135.15, 135.42, 141.47, 142.64 ppm; HRMS (APCI+) (m/z): [M + H]+ calcd. for C38H22, 479.1794; found, 479.1774. [α]D25 −278.90 (c 0.04, CHCH3). (Rp
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Published 11 Aug 2025

Chemical synthesis of glycan motifs from the antitumor agent PI-88 through an orthogonal one-pot glycosylation strategy

  • Shaokang Yang,
  • Xingchun Sun,
  • Hanyingzi Fan and
  • Guozhi Xiao

Beilstein J. Org. Chem. 2025, 21, 1587–1594, doi:10.3762/bjoc.21.122

Graphical Abstract
  • was obtained in 60% overall yield from 20 via sequential global deprotection of the Bn, Cbz, and Bz groups. The structures of the synthetic glycan motifs 1–4 were supported by their 1H and 13C NMR spectra and MALDI–TOF as well as ESI mass spectra. In particular, the anomeric proton signals of 1–4 were
  • -pot synthesis of glycans 1 and 2. One-pot synthesis of glycan 3. One-pot synthesis of glycan 4. Supporting Information Supporting Information File 22: Experimental procedures and spectral data for all new compounds including 1H NMR, 13C NMR, and HRMS. Funding The financial support from the National
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Published 06 Aug 2025

Synthesis of an aza[5]helicene-incorporated macrocyclic heteroarene via oxidation of an o-phenylene-pyrrole-thiophene icosamer

  • Yusuke Matsuo,
  • Aoi Nakagawa,
  • Shu Seki and
  • Takayuki Tanaka

Beilstein J. Org. Chem. 2025, 21, 1561–1567, doi:10.3762/bjoc.21.119

Graphical Abstract
  • heteroarene 5. Supporting Information Supporting Information File 14: Experimental procedures, characterization data of all products, copies of 1H and 13C NMR spectra, optical data, and DFT calculation results. Supporting Information File 15: Crystallographic Information File for compound 4. Supporting
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Published 31 Jul 2025

Azide–alkyne cycloaddition (click) reaction in biomass-derived solvent CyreneTM under one-pot conditions

  • Zoltán Medgyesi and
  • László T. Mika

Beilstein J. Org. Chem. 2025, 21, 1544–1551, doi:10.3762/bjoc.21.117

Graphical Abstract
  • Supporting Information File 1. 1H, 13C, and 19F NMR spectra were collected on a Bruker Avance 300 MHz or Bruker Avance-III 500 MHz instrument and processed by MestReNova v. 14.3.1-31739 (2022) MestreLab Research S. L. GC analyses were performed on an HP 5890 N Series II instrument with Restek RTX®-50
  • . Its purification was performed by vacuum distillation (18–20 mmHg, 114–116 °C) and stored under argon before subsequent use. The purity (>99.99%) was checked by 1H and 13C NMR spectroscopy. 1H NMR (300 MHz, CDCl3, TMS) δ 5.10 (s, 1H, CH), 4.71 (s, 1H, CH), 4.05 (d, J = 7.3 Hz, 1H, CH), 3.96 (t, J
  • = 6.3 Hz, 1H, CH), 2.73–2.02 (m, 4H, CH2); 13C NMR (75 MHz, CDCl3, TMS) δ 200.3 (CO), 101.5 (CH), 73.1 (CH), 67.6 (CH2), 31.1 (CH2), 29.9 (CH2). The NMR data correspond to the published results. Methyl 4-methoxyvalerate and ethyl 4-ethoxyvalerate were prepared using the published method [47]. The
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Published 30 Jul 2025

Ambident reactivity of enolizable 5-mercapto-1H-tetrazoles in trapping reactions with in situ-generated thiocarbonyl S-methanides derived from sterically crowded cycloaliphatic thioketones

  • Grzegorz Mlostoń,
  • Małgorzata Celeda,
  • Marcin Palusiak,
  • Heinz Heimgartner,
  • Marta Denel-Bobrowska and
  • Agnieszka B. Olejniczak

Beilstein J. Org. Chem. 2025, 21, 1508–1519, doi:10.3762/bjoc.21.113

Graphical Abstract
  • analysis of the isolated products of S–H and N–H insertion was carried out based on spectroscopic data (1H and 13C NMR) and the structures of two representatives were established by using the X-ray single crystal diffraction analysis method. Biological activity (cytotoxicity) of some selected products
  • and Me‒N groups located at the above reported shifts. In the 13C NMR spectrum their signals were found in typical regions at 33.5 (NCH3) and 10.3 (SCH3) ppm, respectively. A characteristic signal of the –NCS− atom of the thioaminale moiety, located in the Ad-skeleton was found at 81.2 ppm. Finally
  • (mp 136‒138 °C) in high yield of 86%. The 13C NMR spectrum registered for this compound revealed a shift of the S‒C‒S atom, incorporated into the cyclobutanone ring, at 74.8 ppm. On the other hand, the thioaminal functionality with N‒C‒S moiety located within the tetrazole ring, shows a signal at
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Published 23 Jul 2025

Tautomerism and switching in 7-hydroxy-8-(azophenyl)quinoline and similar compounds

  • Lidia Zaharieva,
  • Vera Deneva,
  • Fadhil S. Kamounah,
  • Nikolay Vassilev,
  • Ivan Angelov,
  • Michael Pittelkow and
  • Liudmil Antonov

Beilstein J. Org. Chem. 2025, 21, 1404–1421, doi:10.3762/bjoc.21.105

Graphical Abstract
  • precoated TLC plates (0.2 mm thick). The identity of all compounds was confirmed employing various spectroscopic techniques including NMR and HRMS–ESI high-resolution mass spectrometry. The 1H and 13C NMR spectra were recorded in CDCl3 or DMSO-d6 at 25 °C on a Bruker Ultrashield Plus 500 spectrometer using
  • ), 7.73–7.33 (m, 2H), 7.02 (d, J = 9.5 Hz, 1H); 13C NMR (125 MHz, CDCl3) δ 171.3, 151.3, 148.5, 145.0, 137.7, 136.5, 131.0, 129.7, 128.8, 125.8, 123.2, 120.7, 120.0; HRMS–ESI (m/z): [M + H]+ calcd for C15H12N3O+, 250.09749; found, 250.09739. Synthesis of 8-(4-hydroxy-1,2,3,5-tetrafluorophenyldiazenyl
  • (dd, J = 1.7, J = 4.3, 1H), 8.28 (dd, J = 1.7, J = 8.2, 1H), 7.86 (d, J = 9.2 Hz, 1H), 7.44 (dd, J = 4.2 Hz, J = 4.2 Hz, 1H), 7.25 (d, J = 9.2 Hz, 1H); 13C NMR (125 MHz, DMSO-d6) δ 156.5, 153.0, 151.0, 145.2, 144.0 (d, J = 240 Hz), 141.2 (d, J = 240 Hz), 136.5, 131.2, 131.1, 123.0, 120.9, 120.0, 110.5
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Published 10 Jul 2025

Reactions of acryl thioamides with iminoiodinanes as a one-step synthesis of N-sulfonyl-2,3-dihydro-1,2-thiazoles

  • Vladimir G. Ilkin,
  • Pavel S. Silaichev,
  • Valeriy O. Filimonov,
  • Tetyana V. Beryozkina,
  • Margarita D. Likhacheva,
  • Pavel A. Slepukhin,
  • Wim Dehaen and
  • Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2025, 21, 1397–1403, doi:10.3762/bjoc.21.104

Graphical Abstract
  • larger or even commercial scale. The structures of compounds 3 were confirmed by 1H and 13C NMR spectroscopy and high-resolution mass spectrometry. The 1H NMR spectra are characterized by signals from protons of the aromatic rings in the range of 8.08–7.32 ppm, singlets for the proton at the C-3 position
  • of the 2,3-dihydro-1,2-thiazole ring in the range of 6.44–6.06 ppm, and multiplets corresponding to the morpholine fragment in the range of 3.80–2.89 ppm or protons of residues of other amino groups in the range of 3.51–1.31 ppm. In the 13C NMR spectra, characteristic signals of the C-4 atom of the
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Published 10 Jul 2025

N-Salicyl-amino acid derivatives with antiparasitic activity from Pseudomonas sp. UIAU-6B

  • Joy E. Rajakulendran,
  • Emmanuel Tope Oluwabusola,
  • Michela Cerone,
  • Terry K. Smith,
  • Olusoji O. Adebisi,
  • Adefolalu Adedotun,
  • Gagan Preet,
  • Sylvia Soldatou,
  • Hai Deng,
  • Rainer Ebel and
  • Marcel Jaspars

Beilstein J. Org. Chem. 2025, 21, 1388–1396, doi:10.3762/bjoc.21.103

Graphical Abstract
  • ion chromatogram and corresponding mass spectrum of compound 4 in the crude extract. Proposed biosynthetic scheme for the formation of compounds (1–4). 1H and 13C NMR data of pseudomonins D–G (1–4). Supporting Information Supporting Information File 10: Experimental information of the 1D and 2D NMR
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Published 04 Jul 2025

Optimized synthesis of aroyl-S,N-ketene acetals by omission of solubilizing alcohol cosolvents

  • Julius Krenzer and
  • Thomas J. J. Müller

Beilstein J. Org. Chem. 2025, 21, 1201–1206, doi:10.3762/bjoc.21.97

Graphical Abstract
  • condensation synthesis of aroyl-S,N-ketene acetals 1 under standard (A)a and modified conditions Bb and Cc. Supporting Information Supporting Information File 6: Experimental details of the synthesis and analytical data of compounds 1 and 3, 1H and 13C NMR spectra of compounds 1 and 3. Acknowledgements We
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Published 20 Jun 2025

Synthesis of β-ketophosphonates through aerobic copper(II)-mediated phosphorylation of enol acetates

  • Alexander S. Budnikov,
  • Igor B. Krylov,
  • Fedor K. Monin,
  • Valentina M. Merkulova,
  • Alexey I. Ilovaisky,
  • Liu Yan,
  • Bing Yu and
  • Alexander O. Terent’ev

Beilstein J. Org. Chem. 2025, 21, 1192–1200, doi:10.3762/bjoc.21.96

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  • . Experimental General: In all experiments rt stands for 22–25 °C. 1H and 13C NMR spectra were recorded on Bruker AVANCE II 300, Bruker Fourier 300HD (300.13 MHz for 1H, 75.47 MHz for 13C and 121.49 MHz for 31P, respectively), and Bruker AVANCE II 600 (600.13 MHz for 1H, 150.92 MHz for 13C, 242.93 MHz for 31P
  • ) spectrometers in CDCl3. Chemical shifts were reported in parts per million (ppm), and the residual solvent peak was used as an internal reference: 1H (СDCl3 δ = 7.26 ppm), 13C (СDCl3 δ = 77.16 ppm). Multiplicity was indicated as follows: s (singlet), d (doublet), t (triplet), q (quartet), m (multiplet
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Published 20 Jun 2025

Selective monoformylation of naphthalene-fused propellanes for methylene-alternating copolymers

  • Kenichi Kato,
  • Tatsuki Hiroi,
  • Seina Okada,
  • Shunsuke Ohtani and
  • Tomoki Ogoshi

Beilstein J. Org. Chem. 2025, 21, 1183–1191, doi:10.3762/bjoc.21.95

Graphical Abstract
  • -shifted to ca. 34 ppm in the 13C NMR spectra due to conversion into methylene groups (Figure 2b and Figures S315 and S316 in Supporting Information File 1). However, all 1H NMR signals were broad, and gel permeation chromatography (GPC) charts indicated broad patterns due to multiple products with varying
  • electrophilic functionalization. a) Synthesis of methylene-alternating copolymers of fully π-fused propellanes. DCE, 1,2-dichloroethane. b) 1H NMR (500 MHz, top) and 13C (126 MHz, bottom) NMR spectra of [4.3.3]_CH2OH and [4.3.3]_linear in CDCl3 at room temperature. Gas adsorption (filled circles) and desorption
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Published 18 Jun 2025

A multicomponent reaction-initiated synthesis of imidazopyridine-fused isoquinolinones

  • Ashutosh Nath,
  • John Mark Awad and
  • Wei Zhang

Beilstein J. Org. Chem. 2025, 21, 1161–1169, doi:10.3762/bjoc.21.92

Graphical Abstract
  • chromatography with 30:70 EtOAc/hexanes. Product structures were confirmed by 1H and 13C NMR analysis and X-ray crystal structure analysis of 8a. Density functional theory (DFT) calculations DFT computations were conducted utilizing Gaussian 16W with the B3LYP functional and the 6-31G(d,p) basis set [21][22
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Published 13 Jun 2025

Investigations of amination reactions on an antimalarial 1,2,4-triazolo[4,3-a]pyrazine scaffold

  • Henry S. T. Smith,
  • Ben Giuliani,
  • Kanchana Wijesekera,
  • Kah Yean Lum,
  • Sandra Duffy,
  • Aaron Lock,
  • Jonathan M. White,
  • Vicky M. Avery and
  • Rohan A. Davis

Beilstein J. Org. Chem. 2025, 21, 1126–1134, doi:10.3762/bjoc.21.90

Graphical Abstract
  • -chlorophenyl)-[1,2,4]triazolo[4,3-a]pyrazine were synthesised, purified (≥95% purity, determined by 1H and 13C NMR and HPLC–MS analysis) and assayed for in vitro antimalarial activity. Results and Discussion Synthesis of aminated triazolopyrazine analogues The amination of 5-chloro-3-(4-chlorophenyl)-[1,2,4
  • previous reports [10]. A single and identical product was obtained from each reaction and the product, 2, was characterised following analysis of HRESIMS and 1D (1H, 13C) and 2D (COSY, HSQC, HMBC, ROESY) NMR data. The HRESIMS data of 2 showed a Na adduct ion at m/z 372.0991 [M + Na]+ (calcd for
  • [δH 3.74 (H-17, J = 5.8, 7.3 Hz), δH 2.98 (H-18, J = 7.3 Hz)]. Three aromatic resonances were also observed, which corresponded to the phenyl moiety [(δH 7.30 (H-21, H-23), 7.28 (H-20, H-24), 7.20 (H-22)], which we have previously characterised for similar triazolopyrazines [12]. The 13C NMR, HSQC and
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Published 10 Jun 2025

Salen–scandium(III) complex-catalyzed asymmetric (3 + 2) annulation of aziridines and aldehydes

  • Linqiang Wang and
  • Jiaxi Xu

Beilstein J. Org. Chem. 2025, 21, 1087–1094, doi:10.3762/bjoc.21.86

Graphical Abstract
  • . Petroleum ether (PE, 60–90 °C fraction) and ethyl acetate (EA) were used as eluent. Reactions were monitored by thin-layer chromatography (TLC) on GF254 silica gel plates (0.2 mm) from Anhui Liangchen Silicon Material Co., Ltd. The plates were visualized by UV light. 1H NMR (400 MHz) and 13C NMR (101 MHz
  • ) spectra were recorded on a Bruker 400 NMR spectrometer (Billerica, MA, USA), usually with TMS as an internal standard for 1H NMR and the centered peak of CDCl3 as an internal standard (77.16) for 13C NMR in CDCl3 solution. The chemical shifts (δ) were reported in parts per million (ppm) relative to
  • mechanism. Gram-scale synthesis. Optimization of reaction conditions.a Supporting Information Supporting Information File 24: Analytic data and copies of 1H and 13C NMR spectra of compounds 1 and 3, copies of HRMS spectra of unknown compound 3 and copies of HLPC profiles of compounds 3. Funding This
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Published 28 May 2025

Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

  • Betty A. Kustiana,
  • Galuh Widiyarti and
  • Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

Graphical Abstract
  • (Scheme 21C) [55]. Kawabata and co-workers (2020) prepared the β-glycoside 66 from α-ᴅ-glucose and cinnamic acid (7) in good yield through the Mitsunobu reaction (Scheme 22) [56]. The 13C kinetic isotope effect experiment (KIE = 1.028) showed that the glycosylation proceeded via SN2 substitution (67). Sun
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Published 28 May 2025

Pd-Catalyzed asymmetric allylic amination with isatin using a P,olefin-type chiral ligand with C–N bond axial chirality

  • Natsume Akimoto,
  • Kaho Takaya,
  • Yoshio Kasashima,
  • Kohei Watanabe,
  • Yasushi Yoshida and
  • Takashi Mino

Beilstein J. Org. Chem. 2025, 21, 1018–1023, doi:10.3762/bjoc.21.83

Graphical Abstract
  • as the base in PhCF3 as the solvent (Scheme 2). An isatin derivative bearing a chloro group at the 4-position afforded the desired product (S)-13b with good yield and enantioselectivity. Similarly, an isatin derivative with a methyl group as an electron-donating group at the 5-position gave (S)-13c
  • allylic amination of acetate 12 with isatin (11a).a Supporting Information Data of thermal racemization of 7, DFT calculations for investigating racemization mechanism of 7, general methods and materials, experimental procedures and characterization data, 1H, 13C and 31P NMR spectra for 9 and 10, 1H, 13C
  • and 31P NMR spectra and HPLC charts for (±)-7, (+)-7 and (–)-7, 1H and 13C NMR spectra and HPLC charts for (S)-13a–k (except (S)-13e) and (S)-16. Supporting Information File 18: Experimental section and compounds characterization. Funding This work was supported by a Grant-in-Aid for Scientific
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Published 23 May 2025
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