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Search for "13C" in Full Text gives 1992 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

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

Graphical Abstract
  • . 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

Studies on the syntheses of β-carboline alkaloids brevicarine and brevicolline

  • Benedek Batizi,
  • Patrik Pollák,
  • András Dancsó,
  • Péter Keglevich,
  • Gyula Simig,
  • Balázs Volk and
  • Mátyás Milen

Beilstein J. Org. Chem. 2025, 21, 955–963, doi:10.3762/bjoc.21.79

Graphical Abstract
  • publications [19][23][24] confirmed the structure with IR and MS data, or by reactivity. Herein, we report the full set of assigned 1H and 13C NMR data for both the base and the dihydrochloride salt. In the course of our efforts devoted to elaborating a new and efficient synthesis of brevicarine (2), we
  • . Assigned 1H and 13C NMR data of brevicarine (2) base and its dihydrochloride salt. Supporting Information CCDC 2410549 (31) contain supplementary crystallographic data for this paper. These data are provided free of charge by The Cambridge Crystallographic Data Centre via http://www.ccdc.ac.uk/data
  • request/cif. Supporting Information File 6: ORTEP diagram of compound 31, synthetic procedures, IR, 1H, 13C, 19F and 2D NMR spectra of compounds 2, 5, 6, 24–28 and 30–32. Supporting Information File 7: Crystallographic information file of compound 31. Supporting Information File 8: Checkcif file for
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Published 20 May 2025

Dicarboxylate recognition based on ultracycle hosts through cooperative hydrogen bonding and anion–π interactions

  • Wen-Hui Mi,
  • Teng-Yu Huang,
  • Xu-Dong Wang,
  • Yu-Fei Ao,
  • Qi-Qiang Wang and
  • De-Xian Wang

Beilstein J. Org. Chem. 2025, 21, 884–889, doi:10.3762/bjoc.21.72

Graphical Abstract
  • . Synthesis of ultracycles. Supporting Information Supporting Information File 4: Experimental details and characterization data (including 1H NMR, 13C NMR, IR, and HRMS of precursor compounds and ultracycles, X-ray data for B4aH, theoretical calculations, and NMR titration data). Funding Financial support
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Letter
Published 06 May 2025

4-(1-Methylamino)ethylidene-1,5-disubstituted pyrrolidine-2,3-diones: synthesis, anti-inflammatory effect and in silico approaches

  • Nguyen Tran Nguyen,
  • Vo Viet Dai,
  • Luc Van Meervelt,
  • Do Thi Thao and
  • Nguyen Minh Thong

Beilstein J. Org. Chem. 2025, 21, 817–829, doi:10.3762/bjoc.21.65

Graphical Abstract
  • ). Furthermore, the 2D 1H–13C HMBC NMR spectrum of 5a also exhibited the correlation between protons of two methyl groups and the same carbon atom resonance at 165.52 ppm, respectively (see Supporting Information File 1). Consequently, the signal at 165.52 ppm in the 13C NMR spectrum corresponds to the sp2
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Published 24 Apr 2025

Development and mechanistic studies of calcium–BINOL phosphate-catalyzed hydrocyanation of hydrazones

  • Carola Tortora,
  • Christian A. Fischer,
  • Sascha Kohlbauer,
  • Alexandru Zamfir,
  • Gerd M. Ballmann,
  • Jürgen Pahl,
  • Sjoerd Harder and
  • Svetlana B. Tsogoeva

Beilstein J. Org. Chem. 2025, 21, 755–765, doi:10.3762/bjoc.21.59

Graphical Abstract
  • that silicon is bound via the carbonyl oxygen in 12, as also shown by DFT computations. This is further corroborated by observation of a 13C NMR signal at 146 ppm for an sp2 carbon in the backbone of the product, which fits better for a C=N than a C=O bond. Recovery of the catalyst resting state 7 is
  • , 13C, and 31P NMR as well as mass-spectrometric data of all synthesized compounds and selected crystal structures. Acknowledgements Portions of this work are included in the doctoral thesis of Christian Andreas Fischer, “Insights in Group 2 Metal Catalysis: New Ways and New Obstacles”, Friedrich
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Published 14 Apr 2025

Orthogonal photoswitching of heterobivalent azobenzene glycoclusters: the effect of glycoligand orientation in bacterial adhesion

  • Leon M. Friedrich and
  • Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2025, 21, 736–748, doi:10.3762/bjoc.21.57

Graphical Abstract
  • functionalization of the ABF4 unit. The EE/ZE/EZ/ZZ isomeric mixture obtained after irradiation of the homobivalent photoswitchable glycocluster 6αMan3αMan 2 had to be determined by integration of the anomeric 1H/13C cross peak of the scaffold mannoside in the 1H,13C HSQC spectrum because the proton signals in the
  • 1H NMR spectrum are not clearly separated (cf. Supporting Information File 1, Figure S3). This procedure was published earlier for the heterobivalent glycocluster 1 [24], however, in comparison to 1, the anomeric 1H/13C cross peaks of the EE, ZE, EZ, and ZZ isomers of 2 are less well resolved and
  • ratios of the individual glycoazobenzene antennas in 2 could be accurately determined by integration of the respective peaks in the 1H,13C HSQC spectrum, namely the anomeric 1H’/13C’ and 1H’’/13C’’ cross peaks (Table 1 and Supporting Information File 1, Figures S4–S6). Comparison of the data collected in
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Published 08 Apr 2025

Synthesis of HBC fluorophores with an electrophilic handle for covalent attachment to Pepper RNA

  • Raphael Bereiter and
  • Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 727–735, doi:10.3762/bjoc.21.56

Graphical Abstract
  • column chromatography was purchased from Macherey-Nagel. 1H and 13C NMR spectra were recorded on a Bruker UltrashieldTM 400 MHz Plus or a 700 MHz Avance Neo spectrometer. Chemical shifts (δ) are reported relative to tetramethylsilane (TMS), referenced to the residual solvent signal (DMSO-d6: 2.50 ppm for
  • 1H NMR and 39.52 ppm for 13C NMR spectra; CDCl3: 7.26 ppm for 1H NMR and 77.16 ppm for 13C NMR spectra). Signal assignments are based on 1H-1H-COSY, 1H-13C-HSQC and 1H-13C-HMBC experiments. High-resolution mass spectra were recorded in positive ion mode unless otherwise noted on a Thermo Scientific Q
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Published 04 Apr 2025

Acyclic cucurbit[n]uril bearing alkyl sulfate ionic groups

  • Christian Akakpo,
  • Peter Y. Zavalij and
  • Lyle Isaacs

Beilstein J. Org. Chem. 2025, 21, 717–726, doi:10.3762/bjoc.21.55

Graphical Abstract
  • (Figure 2a). The 4.0–4.5 ppm region is crowded which precludes precise assignments of the expected resonances for He, Hg, Hi, Hb, and Hc. Similarly, the 13C NMR spectrum recorded for C1 (Figure 2b) shows 15 of the 16 resonances expected based on time averaged C2v-symmetry in solution. For example, we
  • and 150 or 100 MHz for 13C. Melting points were measured on a Meltemp apparatus in open capillary tubes and are uncorrected. IR spectra were measured on a Thermo Nicolet NEXUS 670 FT/IR spectrometer by attenuated total reflectance (ATR) and are reported in cm−1. Mass spectrometry was performed using a
  • (d, J = 8.9 Hz, 2H), 5.41 (d, J = 16.3 Hz, 4H), 4.45–4.40 (m, 4H), 4.35–4.30 (m, 4H), 4.27 (d, J = 15.8 Hz, 2 × 4H), 4.25–4.18 (m, 4H), 4.18–4.13 (m, 4H), 4.12 (d, J = 15.4 Hz, 2H), 1.78 (s, 6H), 1.75 (s, 6H); 13C NMR (100 MHz, D2O/acetone-d6 6:1 (v:v)) 156.7, 155.9, 150.5, 129.3, 116.1, 78.6, 77.4
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Published 03 Apr 2025

Photochemically assisted synthesis of phenacenes fluorinated at the terminal benzene rings and their electronic spectra

  • Yuuki Ishii,
  • Minoru Yamaji,
  • Fumito Tani,
  • Kenta Goto,
  • Yoshihiro Kubozono and
  • Hideki Okamoto

Beilstein J. Org. Chem. 2025, 21, 670–679, doi:10.3762/bjoc.21.53

Graphical Abstract
  • spectra of the fluorescence, synthetic procedures and physical data for the new compounds, theoretical calculation results, copy of 1H and 13C NMR spectra of the prepared compounds. Acknowledgements HO thanks Prof. Kan Wakamatsu (Okayama University of Science) for fruitful discussions and Prof. Takayoshi
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Published 24 Mar 2025
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