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Search for "13C" in Full Text gives 1939 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Study of the interaction of 2H-furo[3,2-b]pyran-2-ones with nitrogen-containing nucleophiles

  • Constantine V. Milyutin,
  • Andrey N. Komogortsev and
  • Boris V. Lichitsky

Beilstein J. Org. Chem. 2025, 21, 556–563, doi:10.3762/bjoc.21.44

Graphical Abstract
  • , 13C NMR spectroscopy and high-resolution MS. 1H NMR spectra of obtained products contain characteristic signals of the protons of the methyl group in the region δ 1.72–2.16 ppm and proton of pyranone fragment in the region δ 5.98–6.62 ppm. Besides that, the key structures of synthesized products were
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Published 13 Mar 2025

Vinylogous functionalization of 4-alkylidene-5-aminopyrazoles with methyl trifluoropyruvates

  • Judit Hostalet-Romero,
  • Laura Carceller-Ferrer,
  • Gonzalo Blay,
  • Amparo Sanz-Marco,
  • José R. Pedro and
  • Carlos Vila

Beilstein J. Org. Chem. 2025, 21, 533–540, doi:10.3762/bjoc.21.41

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  • copies of 1H NMR and 13C NMR spectra. Acknowledgements Access to NMR, MS, and X-ray facilities from the Servei Central de Suport a la Investigació Experimental (SCSIE)-UV and the NMR U26 facility of ICTS “NANBIOSIS” is acknowledged. Funding L.C.-F. thanks the Universitat de València for a predoctoral
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Published 10 Mar 2025

Synthesis of the aggregation pheromone of Tribolium castaneum

  • Biyu An,
  • Xueyang Wang,
  • Ao Jiao,
  • Qinghua Bian and
  • Jiangchun Zhong

Beilstein J. Org. Chem. 2025, 21, 510–514, doi:10.3762/bjoc.21.38

Graphical Abstract
  • )-10. Synthesis of the aggregation pheromone of Tribolium castaneum. Supporting Information Supporting Information File 6: General information, synthesis of compounds 1–12, research on the optical purity of chiral alcohols (R)- and (S)-4, and copies of 1H, 13C and 19F NMR spectra. Funding This
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Published 06 Mar 2025

Organocatalytic kinetic resolution of 1,5-dicarbonyl compounds through a retro-Michael reaction

  • James Guevara-Pulido,
  • Fernando González-Pérez,
  • José M. Andrés and
  • Rafael Pedrosa

Beilstein J. Org. Chem. 2025, 21, 473–482, doi:10.3762/bjoc.21.34

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  • substituents present in the starting Michael adducts. Furthermore, it has been observed that the enantioselectivity of Michael adducts decreases with time in the presence of a catalyst derived from diarylprolinol. Experimental General Information 1H NMR (400 or 500 MHz) and 13C NMR (100 MHz) spectra were
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Published 03 Mar 2025

Synthesis, structure, ionochromic and cytotoxic properties of new 2-(indolin-2-yl)-1,3-tropolones

  • Yurii A. Sayapin,
  • Eugeny A. Gusakov,
  • Inna O. Tupaeva,
  • Alexander D. Dubonosov,
  • Igor V. Dorogan,
  • Valery V. Tkachev,
  • Anna S. Goncharova,
  • Gennady V. Shilov,
  • Natalia S. Kuznetsova,
  • Svetlana Y. Filippova,
  • Tatyana A. Krasnikova,
  • Yanis A. Boumber,
  • Alexey Y. Maksimov,
  • Sergey M. Aldoshin and
  • Vladimir I. Minkin

Beilstein J. Org. Chem. 2025, 21, 358–368, doi:10.3762/bjoc.21.26

Graphical Abstract
  • tautomeric forms. To reveal the predominance of either the (NH) or (OH) tautomeric form of compounds 7a, 7b, 8a, and 8b in solution depending on the nature of the solvent, we carried out a detailed study using compound 7a. A complete signal assignment of 1H and 13C NMR spectra was carried out, based on
  • characteristic values of chemical shifts and cross-peak analysis in two-dimensional spectra of 1H,1H COSY correlations, as well as 1H,13C correlations HSQC, HMBC, and 1H,15N HMBC spectra in DMSO-d6 and CDCl3 (Supporting Information File 2). In the 1H NMR spectrum of 7a in DMSO-d6, the signal of the weak field
  • ,15N HMBC spectrum of 7a there are cross peaks of the indolenine nitrogen atom at 162.2 ppm with a weak field proton at δH 14.23 ppm, as well as aromatic protons H(4') and H(5') with δH 7.94 ppm and 7.97 ppm, respectively (Supporting Information File 2, Figure S19). In the two-dimensional 1H,13C HMBC
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Published 17 Feb 2025

Synthesis, characterization, antimicrobial, cytotoxic and carbonic anhydrase inhibition activities of multifunctional pyrazolo-1,2-benzothiazine acetamides

  • Ayesha Saeed,
  • Shahana Ehsan,
  • Muhammad Zia-ur-Rehman,
  • Erin M. Marshall,
  • Sandra Loesgen,
  • Abdus Saleem,
  • Simone Giovannuzzi and
  • Claudiu T. Supuran

Beilstein J. Org. Chem. 2025, 21, 348–357, doi:10.3762/bjoc.21.25

Graphical Abstract
  • and 13C NMR spectroscopy. All compounds were tested against five human microbial strains including three different strains of Staphylococcus aureus (ATCC 25923, ATCC BAA-41, and ATCC BAA-44), Escherichia coli (ATCC 8739), and Candida albicans (ATCC 90027) to evaluate their antibiotic potential. The
  • oxygen atom [50]. Preferential N-alkylation (over O-alkylation) of 1,2-benzothiazine scaffolds has also been carried out by Ahmad and co-workers in 2014 and Szczęśniak-Sięga and companions in 2018 [37][51]. Structure elucidation of all the synthesized derivatives was carried out using 1H, 13C NMR, and
  • compounds 7a–h and 7i–n shared a singlet for the N-methyl protons in the range of 3.07 to 3.10 ppm. Signals for aromatic protons were recorded from 6.70 to 8.19 ppm depending upon the extent of shielding/deshielding. The 13C NMR spectra exhibited distinct signals for the synthesized compounds 7a–h: one
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Published 12 Feb 2025

Synthesis of new condensed naphthoquinone, pyran and pyrimidine furancarboxylates

  • Kirill A. Gomonov,
  • Vasilii V. Pelipko,
  • Igor A. Litvinov,
  • Ilya A. Pilipenko,
  • Anna M. Stepanova,
  • Nikolai A. Lapatin,
  • Ruslan I. Baichurin and
  • Sergei V. Makarenko

Beilstein J. Org. Chem. 2025, 21, 340–347, doi:10.3762/bjoc.21.24

Graphical Abstract
  • data, they luminesce in DMSO solution when irradiated with light at wavelengths of 352 and 283 nm. Compounds 7a–f are capable of existing as lactim–lactam tautomers due to the presence of an amide fragment in their structure (Scheme 7). At the same time, the 1H and 13C NMR spectra of compounds 7a–f
  • indicate their individuality. The presence of a broadened signal in the 1H NMR spectra (DMSO-d6) in the region of 12.49–12.84 ppm and a C4 signal in the 13C NMR spectra (DMSO-d6) in the region of 158.1–159.0 ppm does not allow us to unambiguously determine the tautomeric form of compounds 7a–f in solution
  • = 10−5 mol/L). 1Н, 13С{1H}, 1H-13C HMQC, and 1H-13C HMBC NMR spectra were registered on a Jeol ECX–400A instrument at 400 (for 1H nuclei) and 100 MHz (for 13С nuclei) in CDCl3 (δH 7.26, δC 77.16 ppm) and DMSO-d6 (δH 2.47, δC 40.0 ppm) using residual signals of the nondeuterated solvent as the
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Published 12 Feb 2025

Antibiofilm and cytotoxic metabolites from the entomopathogenic fungus Samsoniella aurantia

  • Rita Toshe,
  • Syeda J. Khalid,
  • Blondelle Matio Kemkuignou,
  • Esteban Charria-Girón,
  • Paul Eckhardt,
  • Birthe Sandargo,
  • Kunlapat Nuchthien,
  • J. Jennifer Luangsa-ard,
  • Till Opatz,
  • Hedda Schrey,
  • Sherif S. Ebada and
  • Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 327–339, doi:10.3762/bjoc.21.23

Graphical Abstract
  • that it is a related derivative to two yellow pyridone pigments, farinosones A and B, that were previously reported from Cordyceps farinosa syn. Paecilomyces farinosus [8][9]. A detailed comparison of the 1H and 13C NMR data of 1 and farinosones A/B revealed that instead of a deshielded pyridone
  • ), 300 (0.5), 265 (0.6) 218 (2.4); NMR data (1H: 500 MHz, 13C: 125 MHz, DMSO-d6) see Table 1; HRESIMS m/z: [M – H2O + H]+ calcd for C25H28NO4+, 406.2026; found, 406.2020; [M + H]+ calcd for C25H30NO5+, 424.2118; found, 424.2126; [M + Na]+ calcd for C25H29NNaO5+, 446.1962; found, 446.1947. Farinosone A (2
  • ): Pale yellow amorphous solid; UV–vis (MeOH) λmax: 368, 224, 200 nm; NMR data (1H: 500 MHz, 13C: 125 MHz, acetone-d6) comparable to the previously described spectral data [8]; HRESIMS m/z: [M + H]+ calcd for C25H28NO4+, 406.2103; found, 406.2103. Farinosone B (3): Bright yellow powder; UV–vis (MeOH) λmax
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Published 11 Feb 2025

Molecular diversity of the reactions of MBH carbonates of isatins and various nucleophiles

  • Zi-Ying Xiao,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2025, 21, 286–295, doi:10.3762/bjoc.21.21

Graphical Abstract
  • 2390715), 7a (CCDC 2390716) and 8a (CCDC 2390717) have been deposited at the Cambridge Crystallographic Database Center. Supporting Information File 2: Experimental procedures, 1H, 13C NMR, and HRMS spectra for all new compounds. Funding This work was financially supported by the National Natural Science
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Published 06 Feb 2025

Synthesis and characterizations of highly luminescent 5-isopropoxybenzo[rst]pentaphene

  • Islam S. Marae,
  • Jingyun Tan,
  • Rengo Yoshioka,
  • Zakaria Ziadi,
  • Eugene Khaskin,
  • Serhii Vasylevskyi,
  • Ryota Kabe,
  • Xiushang Xu and
  • Akimitsu Narita

Beilstein J. Org. Chem. 2025, 21, 270–276, doi:10.3762/bjoc.21.19

Graphical Abstract
  • ferric chloride (FeCl3) gave BPP-dione 4 in 70% yield. The chemical structures of BPP-OiPr 3 and BPP-dione 4 were characterized by 1H and 13C NMR spectroscopy as well as mass spectrometry (see Supporting Information File 1, Figures S8–S11). A single crystal of BPP-OiPr 3 suitable for X-ray diffraction
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Published 04 Feb 2025

Three-component reactions of conjugated dienes, CH acids and formaldehyde under diffusion mixing conditions

  • Dmitry E. Shybanov,
  • Maxim E. Kukushkin,
  • Eugene V. Babaev,
  • Nikolai V. Zyk and
  • Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 262–269, doi:10.3762/bjoc.21.18

Graphical Abstract
  • UV lamp. 1H and 13C NMR spectra were recorded on Bruker Avance and Agilent 400-MR spectrometers (400 MHz for 1H, 100 MHz for 13C). Chemical shifts are reported in ppm relative to TMS. General procedure for the three-component reactions under diffusion mixing conditions A mixture of 1.0 mmol CH acid
  • , CDCl3, δ) 7.98–7.89 (m, 4H), 7.45–7.38 (m, 2H), 7.36–7.28 (m, 4H), 6.30 (dd, J = 5.7, 3.0 Hz, 1H), 5.74 (dd, J = 5.7, 2.9 Hz, 1H), 3.94–3.90 (m, 1H), 3.00–2.95 (m, 1H), 2.84 (dd, J = 12.1, 2.9 Hz, 1H), 2.18 (dd, J = 12.1, 3.7 Hz, 1H), 1.76–1.71 (m, 1H), 1.63–1.54 (m, 1H); 13C NMR (101 MHz, CDCl3, δ
  • ), 6.22–6.16 (m, 1H), 6.09–6.04 (m, 1H), 5.44–5.39 (m, 1H), 3.18–3.08 (m, 1H), 2.75 (dd, J = 14.3, 6.1 Hz, 1H), 2.71–2.62 (m, 1H), 2.58 (dd, J = 14.3, 4.8 Hz, 1H), 2.34–2.25 (m, 1H); 13C NMR (101 MHz, CDCl3, δ) 198.4, 165.1, 139.1, 137.5, 135.6, 131.4, 130.9, 129.7 (2C), 129.6 (2C), 129.5 (2C), 127.7 (3C
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Published 04 Feb 2025

Effect of substitution position of aryl groups on the thermal back reactivity of aza-diarylethene photoswitches and prediction by density functional theory

  • Misato Suganuma,
  • Daichi Kitagawa,
  • Shota Hamatani and
  • Seiya Kobatake

Beilstein J. Org. Chem. 2025, 21, 242–252, doi:10.3762/bjoc.21.16

Graphical Abstract
  • previous work [56][57], whereas compounds N4 and I1–I4 were synthesized according to Scheme 2 in the Experimental section. The chemical structures of all compounds were confirmed by 1H NMR and 13C NMR spectroscopy and high-resolution mass spectrometry. 1H NMR and 13C NMR spectra are shown in Supporting
  • by distillation before use. 1H NMR (300 MHz) and 13C NMR (75 MHz) spectra were recorded on a Bruker AV-300N spectrometer with tetramethylsilane (TMS) as the internal standard. High-resolution mass spectra (HRMS) were measured on a JEOL AccTOF LC mass spectrometer. UV–vis absorption spectra were
  • , 3H, CH3), 7.45–7.50 (m, 3H, aromatic H), 7.93–7.97 (m, 2H, aromatic H); 13C NMR (75 MHz, CDCl3) δ = 17.25, 17.31, 111.87, 126.93, 129.29, 131.31, 132.62, 157.67, 171.07, 171.09; HRMS–DART+ (m/z): [M + H]+ calcd for C15H9F7NS+, 368.0344; found, 368.0350. 3-Methyl-2-(perfluorocyclopent-1-en-1-yl
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Published 31 Jan 2025

Nickel-catalyzed cross-coupling of 2-fluorobenzofurans with arylboronic acids via aromatic C–F bond activation

  • Takeshi Fujita,
  • Haruna Yabuki,
  • Ryutaro Morioka,
  • Kohei Fuchibe and
  • Junji Ichikawa

Beilstein J. Org. Chem. 2025, 21, 146–154, doi:10.3762/bjoc.21.8

Graphical Abstract
  • important in pharmaceuticals and agrochemicals [41][42][43][44][45][46][47], we expect that this method will provide a novel and efficient approach for producing these valuable compounds. Experimental General: 1H NMR, 13C NMR, 19F NMR, and 31P NMR were recorded on a Bruker Avance 500 or a JEOL ECS-400
  • spectrometer. Chemical shift values are given in ppm relative to internal Me4Si (for 1H NMR: δ = 0.00 ppm), CDCl3 (for 13C NMR: δ = 77.0 ppm), C6F6 (for 19F NMR: δ = 0.0 ppm), and H3PO4 (for 31P NMR: δ = 0.0 ppm). IR spectra were recorded on a Horiba FT-730 spectrometer. Mass spectra were measured on a JEOL
  • Hz, 1H), 7.49–7.46 (m, 2H), 7.35 (dd, J = 7.7, 7.6 Hz, 1H), 7.16 (d, J = 7.6 Hz, 1H), 2.44 (s, 3H); 13C NMR (126 MHz, CDCl3) δ 155.6, 152.3, 138.5, 130.5, 130.4, 129.1, 128.8, 128.7, 127.6, 126.2, 125.3, 125.1, 124.6, 124.5, 123.4, 121.9, 112.3, 100.3, 21.5; IR (KBr): 3051, 1606, 1487, 1387, 1280
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Published 15 Jan 2025

Facile one-pot reduction of β-nitrostyrenes to phenethylamines using sodium borohydride and copper(II) chloride

  • Laura D’Andrea and
  • Simon Jademyr

Beilstein J. Org. Chem. 2025, 21, 39–46, doi:10.3762/bjoc.21.4

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  • aromatic compounds. Experimental NMR spectra were recorded on Bruker Avance 400 MHz or Bruker Avance III HD 600 MHz spectrometers. Residual solvent peaks (CDCl3, D2O, CD3OD, (CD3)2SO) were used as internal standard (7.26, 4.79, 3.31, and 2.50 ppm for 1H, and 77.16, 49, and 39.52 ppm for 13C, respectively
  • hydrochloride (1b): The product was isolated by use of (II) as an amorphous white solid (83%). 1H NMR (600 MHz, CD3OD) δ 2.97 (m, J = 5.18 Hz, 2H), 3.18 (m, J = 5.24 Hz, 2H), 7.28 (m, J = 5.0 Hz, 3H), 7.35 (m, J = 7.6 Hz, 2H); 13C NMR (151 MHz, CD3OD) δ 34.55, 41.98, 128.26, 129.77, 129.99, 137.92; ESI-MS m/z
  • , J = 8.4, 2.5, 0.2 Hz, 2H); 13C NMR (151 MHz, CD3OD) δ 33.75, 42.14, 55.71, 115.42, 129.60, 130.78, 160.47; ESI-MS m/z: [M + 1]+ 151.1; found, 152.1; mp 214–216 °C. 1-(2,5-Dimethoxyphenyl)propan-2-amine hydrochloride (3b): The product was isolated by use of (II) as a white solid (62%). 1H NMR (600
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Published 07 Jan 2025

Synthesis, structure and π-expansion of tris(4,5-dehydro-2,3:6,7-dibenzotropone)

  • Yongming Xiong,
  • Xue Lin Ma,
  • Shilong Su and
  • Qian Miao

Beilstein J. Org. Chem. 2025, 21, 1–7, doi:10.3762/bjoc.21.1

Graphical Abstract
  • . This corresponds to a molecular formula of C119H122O9, which is in agreement with the fully fused product 11 in its protonated form. Unfortunately, clean 1H and 13C NMR spectra of this product could not be obtained to allow full characterization of this product. Efforts to increase the yield of 11
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Published 02 Jan 2025

Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

  • Shuxian Qiu,
  • Duan Dong,
  • Jiahui Li,
  • Huiting Wen,
  • Jinpeng Li,
  • Yu Yang,
  • Shengxian Zhai and
  • Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

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  • available 2-bromo-4-fluoro-1-nitrobenzene, featuring a noble-metal-free system, mild reaction conditions, and a good yield, especially for the final Cs2CO3-facilitated nucleophilic substitution (77–91% yield). The characterization data obtained from IR and NMR spectroscopy (1H, 13C, 19F, and 31P) as well as
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Published 30 Dec 2024

Synthesis of acenaphthylene-fused heteroarenes and polyoxygenated benzo[j]fluoranthenes via a Pd-catalyzed Suzuki–Miyaura/C–H arylation cascade

  • Merve Yence,
  • Dilgam Ahmadli,
  • Damla Surmeli,
  • Umut Mert Karacaoğlu,
  • Sujit Pal and
  • Yunus Emre Türkmen

Beilstein J. Org. Chem. 2024, 20, 3290–3298, doi:10.3762/bjoc.20.273

Graphical Abstract
  • , characterization data, and copies of 1H and 13C{1H} NMR spectra. Acknowledgements The data presented in this article are partially taken from the M.Sc. theses of Merve Yence (Bilkent University, 2019) and Dilgam Ahmadli (Bilkent University, 2021). Funding Financial support for some parts of this work from the
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Published 23 Dec 2024

Giese-type alkylation of dehydroalanine derivatives via silane-mediated alkyl bromide activation

  • Perry van der Heide,
  • Michele Retini,
  • Fabiola Fanini,
  • Giovanni Piersanti,
  • Francesco Secci,
  • Daniele Mazzarella,
  • Timothy Noël and
  • Alberto Luridiana

Beilstein J. Org. Chem. 2024, 20, 3274–3280, doi:10.3762/bjoc.20.271

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  • nm, 25 °C, overnight. The yield of 3 was calculated by 1H NMR with 1,1,2-trichloroethene as external standard. Supporting Information Supporting Information File 52: 1H NMR, 13C NMR, and HRMS spectra of all the synthesized compounds. Acknowledgements We are grateful to University Research Services
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Published 17 Dec 2024

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

  • Yang Chen,
  • Jiao He,
  • Hang Lin,
  • Hai-Feng Wang,
  • Ping Hu,
  • Bi-Qin Wang,
  • Ke-Qing Zhao and
  • Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

Graphical Abstract
  • ) was synthesized via consecutive Suzuki coupling and Scholl reaction in a total yield of 77%. The synthesis, molecular structures, nomenclature, and synthetic yields of all compounds are shown in general Scheme 1. All prepared molecules were fully characterized by NMR (1H, 19F and 13C), HRMS, and CHN
  • '-hexafluoro-6,6',7,7',10,10',11,11'-octakisalkoxy-2,2'-bitriphenylene dimers (G55, G66 and G48). Mesophases’ parameters. Supporting Information Synthesis (Schemes S1–S3) and characterization, 1H, 13C, and 19F NMR (Figures S1–S21), HRMS (Figures S22–S32), EA, single crystal X-ray structures (Figures S33, S34
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Published 16 Dec 2024

Intramolecular C–H arylation of pyridine derivatives with a palladium catalyst for the synthesis of multiply fused heteroaromatic compounds

  • Yuki Nakanishi,
  • Shoichi Sugita,
  • Kentaro Okano and
  • Atsunori Mori

Beilstein J. Org. Chem. 2024, 20, 3256–3262, doi:10.3762/bjoc.20.269

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  • , J = 8.4, 8.0, 1.2 Hz, 1H), 7.37 (d, J = 8.4 Hz, 1H), 7.30 (dd, J = 8.0, 7.6 Hz, 1H), 4.40 (dd, J = 8.0, 7.6 Hz, 2H), 1.76–1.88 (m, 2H), 1.44–1.56 (m, 2H), 1.18–1.42 (m, 8H), 0.86 (t, J = 6.8 Hz, 3H); 13C{1H} NMR (CDCl3) δ 160.1, 148.4, 142.0, 136.7, 131.1, 130.5, 130.2, 130.1, 129.1, 128.7, 127.7
  • . Supporting Information File 48: Additional experimental details and copies of 1H and 13C{1H} NMR spectra. Acknowledgements We thank Professor Shigeki Mori and Ms. Rimi Konishi (Ehime University) for the X-ray crystallographic analysis.
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Published 13 Dec 2024

Ceratinadin G, a new psammaplysin derivative possessing a cyano group from a sponge of the genus Pseudoceratina

  • Shin-ichiro Kurimoto,
  • Kouta Inoue,
  • Taito Ohno and
  • Takaaki Kubota

Beilstein J. Org. Chem. 2024, 20, 3215–3220, doi:10.3762/bjoc.20.267

Graphical Abstract
  • existence of a substituted benzenoid chromophore was suggested by the UV absorption maximum at 258 nm. The presence of hydroxy and/or amino groups and a carbonyl group was indicated by IR absorptions at 3337 cm−1 and 1671 cm−1, respectively. The analysis of the HSQC spectrum, along with the 1H and 13C NMR
  • (partial structures a and b, respectively, in Figure 2), which were characteristic of psammaplysins, in ceratinadin G (1) was suggested by comparison of its 1H and 13C NMR data with those of known psammaplysin derivatives such as psammaplysins A and F (2) [4][5][6][10][11][12]. HMBC correlations (H-1/C-2
  • 116.9) and the molecular formula of compound 1, it was inferred that a cyano group is attached to C-22. The 13C NMR chemical shifts of C-22 and C-23 closely matched those of the corresponding carbons in known synthetic compounds with an aminoacetonitrile moiety, further supporting the presence of a
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Published 09 Dec 2024

Discovery of ianthelliformisamines D–G from the sponge Suberea ianthelliformis and the total synthesis of ianthelliformisamine D

  • Sasha Hayes,
  • Yaoying Lu,
  • Bernd H. A. Rehm and
  • Rohan A. Davis

Beilstein J. Org. Chem. 2024, 20, 3205–3214, doi:10.3762/bjoc.20.266

Graphical Abstract
  • protons indicating the presence of a symmetrical aromatic moiety, were observed. The 13C NMR (Table 1) spectrum of 4 showed two carbonyls (δC 164.4, 173.9), with the carbonyl at δC 164.4 readily assigned to an acrylamide group, which is present in all previously published ianthelliformisamine molecules [7
  • ]. The 13C NMR (Table 1) data of 5 displayed six aliphatic carbons (δC 35.9, 26.1, 44.8, 46.3, 21.1, 30.4) and two carbonyl signals (δC 164.9, 173.6). Similarly to the other ianthelliformisamines, the aromatic (δC 131.6) and olefin (δC 124.5, 135.2) carbons were observed [7]. COSY correlations associated
  • carbon signal. Although a downfield exchangeable CO2H proton was not observed in the 1H NMR spectrum of 5, a carboxylic acid moiety was assigned based on the 13C NMR shift value (δC 173.6) [17], and analysis of the HRESIMS ion at m/z 477.0022 [M + H]+, which confirmed the molecular formula to be
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Published 09 Dec 2024

Multicomponent reactions driving the discovery and optimization of agents targeting central nervous system pathologies

  • Lucía Campos-Prieto,
  • Aitor García-Rey,
  • Eddy Sotelo and
  • Ana Mallo-Abreu

Beilstein J. Org. Chem. 2024, 20, 3151–3173, doi:10.3762/bjoc.20.261

Graphical Abstract
  • compounds with high yields (84–92%). The three most promising compounds of the library (13a, 13b, and 13c) were selected for further detailed characterization. In vitro evaluation was performed employing a high-performance liquid chromatography (HPLC)-based methodology, using the fluorogenic histone
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Published 03 Dec 2024

Synthesis of the 1,5-disubstituted tetrazole-methanesulfonylindole hybrid system via high-order multicomponent reaction

  • Cesia M. Aguilar-Morales,
  • América A. Frías-López,
  • Nadia V. Emilio-Velázquez,
  • Alejandro Islas-Jácome,
  • Angelica Judith Granados-López,
  • Jorge Gustavo Araujo-Huitrado,
  • Yamilé López-Hernández,
  • Hiram Hernández-López,
  • Luis Chacón-García,
  • Jesús Adrián López and
  • Carlos J. Cortés-García

Beilstein J. Org. Chem. 2024, 20, 3077–3084, doi:10.3762/bjoc.20.256

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  • and resource optimization. In addition, all the target compounds were fully characterized using 1H and 13C NMR spectroscopy and HRMS. It is important to mention that this protocol cannot be considered a true one-pot synthesis, as it requires a solvent exchange between reaction steps (e.g., from
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Published 26 Nov 2024

Extension of the π-system of monoaryl-substituted norbornadienes with acetylene bridges: influence on the photochemical conversion and storage of light energy

  • Robin Schulte,
  • Dustin Schade,
  • Thomas Paululat,
  • Till J. B. Zähringer,
  • Christoph Kerzig and
  • Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 3061–3068, doi:10.3762/bjoc.20.254

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  • because by-products interfered with the chromatographic separation; however, these yields are similar to the ones reported for resembling norbornadienes [34][37]. The novel compounds 1h–l,n were identified and fully characterized by NMR spectroscopy (1H, 13C, COSY, HSQC, HMBC), melting point, and
  • elemental analysis. All products showed the characteristic 1H NMR spectroscopic signals of norbornadienes, in particular two signals at ca. 2.10 ppm and 2.20 ppm (7-CH2) and two broad singlets between 3 and 4 ppm (bridgehead 1- and 4-CH). In addition, typical 13C NMR shifts of the aryl-substituted
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Published 21 Nov 2024
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