Search results

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

Ugi bisamides based on pyrrolyl-β-chlorovinylaldehyde and their unusual transformations

  • Alexander V. Tsygankov,
  • Vladyslav O. Vereshchak,
  • Tetiana O. Savluk,
  • Serhiy M. Desenko,
  • Valeriia V. Ananieva,
  • Oleksandr V. Buravov,
  • Yana I. Sakhno,
  • Svitlana V. Shishkina and
  • Valentyn A. Chebanov

Beilstein J. Org. Chem. 2024, 20, 1773–1784, doi:10.3762/bjoc.20.156

Graphical Abstract
  • stirring for three hours (Scheme 3, conditions A). However, the results of this attempted post-Ugi transformation were quite unexpected: Instead of acid 11, we isolated the amide of the unsaturated derivative of pyruvic acid 10a according to the 1H and 13C NMR spectra and mass spectrometry data. In order
  • conventional thermal heating, amide 10a was isolated, albeit in a lower yield and accompanied with tar formation. In addition to the 1H, 13C NMR spectra and mass spectrometry data, the structure of compound 10d was established by X-ray diffraction analysis (Figure 3). It was also found that the substituents at
  • case of bisamides 5d, 6a, 6c, 7b, 8a, and 8c (Table 2), additional transformation products were also isolated from the reaction mixture. According to 1H and 13C NMR, MS, and X-ray diffraction studies these were the corresponding ketobisamides 12, which are products of a nucleophilic substitution of the
PDF
Album
Supp Info
Full Research Paper
Published 26 Jul 2024

Polymer degrading marine Microbulbifer bacteria: an un(der)utilized source of chemical and biocatalytic novelty

  • Weimao Zhong and
  • Vinayak Agarwal

Beilstein J. Org. Chem. 2024, 20, 1635–1651, doi:10.3762/bjoc.20.146

Graphical Abstract
  • group in 25 is rare. Feeding [1-13C]acetate to the culture resulted the enrichment of C1, C3, C5, C7, and C9 carbons, which verified the origin of the carbon skeleton as being fatty acid-derived. Feeding experiments with ʟ-[methyl-13C]methionine yielded only enrichment of C11 methyl, indicating that
PDF
Album
Review
Published 17 Jul 2024

New triazinephosphonate dopants for Nafion proton exchange membranes (PEM)

  • Fátima C. Teixeira,
  • António P. S. Teixeira and
  • C. M. Rangel

Beilstein J. Org. Chem. 2024, 20, 1623–1634, doi:10.3762/bjoc.20.145

Graphical Abstract
  • for 35Cl and 37Cl isotopes, respectively, with an approximately 3/4 and 1/4 proportion. The symmetry of the obtained compound TP1 gives simple NMR spectra, with the 31P NMR spectrum showing a singlet signal (Figure 2) and the signal at 169.5 ppm, on the 13C NMR spectrum, confirming the presence of a
  • different conditions tested. The spectroscopic data are in agreement with the proposed structure for compound TP3 (Scheme 5), namely the presence of the chlorine atom in the mass spectrum, due to the presence of isotope peaks, the signal at 168.2 ppm at 13C NMR spectrum attributed to the carbon atom bonded
  • characterization of the dopants was carried out by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). 1H, 13C and 31P NMR characterization was done using different one- and two-dimensional techniques, and were obtained on a Bruker Avance III HD
PDF
Album
Supp Info
Full Research Paper
Published 17 Jul 2024

Primary amine-catalyzed enantioselective 1,4-Michael addition reaction of pyrazolin-5-ones to α,β-unsaturated ketones

  • Pooja Goyal,
  • Akhil K. Dubey,
  • Raghunath Chowdhury and
  • Amey Wadawale

Beilstein J. Org. Chem. 2024, 20, 1518–1526, doi:10.3762/bjoc.20.136

Graphical Abstract
  • ent-3aa-ent-3na, 1H, 13C NMR spectra of 3aa–na, 1H NMR of ent-3aa–ent-3na and their HPLC traces and single crystal data of ent-3ba. Acknowledgements The authors are thankful to Ms. Ketki Lele for her help in some preliminary experiments. Funding The authors thank the Department of Atomic Energy (DAE
PDF
Album
Supp Info
Full Research Paper
Published 09 Jul 2024

Tetrabutylammonium iodide-catalyzed oxidative α-azidation of β-ketocarbonyl compounds using sodium azide

  • Christopher Mairhofer,
  • David Naderer and
  • Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1510–1517, doi:10.3762/bjoc.20.135

Graphical Abstract
  • pronucleophile, followed by a phase-transfer-catalyzed nucleophilic substitution by the azide. Furthermore, we also obtained a first proof-of-concept for the conceptually analogous α-nitration by using NaNO2 under otherwise identical conditions. Experimental General details 1H, 13C and 19F NMR spectra were
  • Research Center “RERI uasb”. All NMR spectra were referenced on the solvent residual peak (CDCl3: δ = 7.26 ppm for 1H NMR, δ = 77.16 ppm for 13C NMR,19F NMR unreferenced). IR spectra were recorded on a Bruker Alpha II FTIR spectrometer with diamond ATR-module using the OPUS software package. HRMS spectra
  • = 17.2 Hz, 1H), 2.99 (d, J = 17.2 Hz, 1H), 1.45 (s, 9H); 13C NMR (75 MHz, CDCl3, 298 K, δ/ppm) 198.1, 167.4, 152.3, 136.4, 133.3, 128.4, 126.5, 125.6, 84.6, 70.6, 38.6, 28.0; IR (neat, FT-ATR, 298 K, ν̃/cm−1): 2984, 2928, 2853, 2110, 1747, 1736, 1718, 1604, 1589, 1548, 1466, 1431, 1397, 1372, 1353, 1326
PDF
Album
Supp Info
Full Research Paper
Published 05 Jul 2024

Towards an asymmetric β-selective addition of azlactones to allenoates

  • Behzad Nasiri,
  • Ghaffar Pasdar,
  • Paul Zebrowski,
  • Katharina Röser,
  • David Naderer and
  • Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1504–1509, doi:10.3762/bjoc.20.134

Graphical Abstract
  • giving access to the acyclic α-amino acid-based amides 6 straightforwardly. Experimental General details 1H and 13C NMR spectra were recorded on a Bruker Avance III 300 MHz spectrometer with a broad band observe probe. All NMR spectra were referenced on the solvent residual peak (CDCl3: δ 7.26 ppm for 1H
  • NMR and δ 77.16 ppm for 13C NMR). NMR data are reported as follows: chemical shift (δ ppm), multiplicity (s = singlet, d = doublet, t = triplet, q = quartet, m = multiplet, dd = doublet of doublet), coupling constants (Hz), relative integration value. High-resolution mass spectra were obtained using a
  • ), 3.52–3.16 (m, 4H), 1.15 (t, J = 7.1 Hz, 3H); 13C NMR (75 MHz, CDCl3, 298.0 K) δ/ppm = 177.4, 171.0, 160.3, 139.1, 133.8, 132.6, 130.5, 128.6, 128.0, 127.8, 127.3, 125.6, 118.1, 75.9, 60.9, 44.9, 39.3, 13.9; IR (neat): 3080, 3070, 2917, 1815, 1732, 1656, 1480, 1175, 1093, 1059, 1030, 974, 893, 694 cm−1
PDF
Album
Supp Info
Full Research Paper
Published 04 Jul 2024

Photoswitchable glycoligands targeting Pseudomonas aeruginosa LecA

  • Yu Fan,
  • Ahmed El Rhaz,
  • Stéphane Maisonneuve,
  • Emilie Gillon,
  • Maha Fatthalla,
  • Franck Le Bideau,
  • Guillaume Laurent,
  • Samir Messaoudi,
  • Anne Imberty and
  • Juan Xie

Beilstein J. Org. Chem. 2024, 20, 1486–1496, doi:10.3762/bjoc.20.132

Graphical Abstract
  • silica gel (60 Å pore size, 40–63 µm). 1H and 13C NMR spectra were recorded on a JEOL ECS-400 spectrometer or on Bruker Avance 300 and 400 spectrometers. Structural assignments were made with additional information from gCOSY, HMBC, and gHMQC experiments. High-resolution mass spectra (HRMS) were
PDF
Album
Supp Info
Full Research Paper
Published 03 Jul 2024

Synthesis of 2-benzyl N-substituted anilines via imine condensation–isoaromatization of (E)-2-arylidene-3-cyclohexenones and primary amines

  • Lu Li,
  • Na Li,
  • Xiao-Tian Mo,
  • Ming-Wei Yuan,
  • Lin Jiang and
  • Ming-Long Yuan

Beilstein J. Org. Chem. 2024, 20, 1468–1475, doi:10.3762/bjoc.20.130

Graphical Abstract
  • -cyclohexenone. This is further supported by the 13C NMR spectrum, which contains two peaks at δ = 38.4 and 47.7 indicating the two types of benzylic carbons. The NMR data of known compound 4ab were also in good correlation with previously reported data [19]. The synthetic practicability of the protocol was
PDF
Album
Supp Info
Full Research Paper
Published 02 Jul 2024

Selectfluor and alcohol-mediated synthesis of bicyclic oxyfluorination compounds by Wagner–Meerwein rearrangement

  • Ziya Dağalan,
  • Muhammed Hanifi Çelikoğlu,
  • Saffet Çelik,
  • Ramazan Koçak and
  • Bilal Nişancı

Beilstein J. Org. Chem. 2024, 20, 1462–1467, doi:10.3762/bjoc.20.129

Graphical Abstract
  • rearrangement. Optimizing the conditions for the oxyfluorination of bicyclic alkenesa. Supporting Information Supporting Information File 2: Experimental procedures, copies of 1H NMR, 13C NMR, and HRMS(Q-TOF) spectra. Acknowledgements The authors wish to express their sincerest gratitude to Dr. Barış Anıl for
PDF
Album
Supp Info
Full Research Paper
Published 01 Jul 2024

Rapid construction of tricyclic tetrahydrocyclopenta[4,5]pyrrolo[2,3-b]pyridine via isocyanide-based multicomponent reaction

  • Xiu-Yu Chen,
  • Ying Han,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2024, 20, 1436–1443, doi:10.3762/bjoc.20.126

Graphical Abstract
  • ), 2.28 (s, 3H, CH3), 1.89–1.86 (m, 2H, CH2), 1.80–1.68 (m, 4H, CH2), 1.55–1.33 (m, 3H, CH2), 1.20–1.13 (m, 1H, CH2) ppm; 13C NMR (100 MHz, CDCl3) δ 170.1, 168.3, 167.8, 166.5, 162.5, 161.9, 157.2, 157.0, 144.7, 137.6, 131.4, 130.9, 129.1, 128.0, 127.9, 127.1, 112.0, 113.6, 111.0, 110.2, 98.9, 84.0, 72.2
  • 2346135) and 6g (CCDC 2346136) have been deposited at the Cambridge Crystallographic Database Center (http://www.ccdc.cam.ac.uk). Supporting Information File 24: Characterization data and 1H NMR, 13C NMR, and HRMS spectra of compounds. Funding This work was financially supported by the National Natural
PDF
Album
Supp Info
Full Research Paper
Published 28 Jun 2024

Rhodium-catalyzed homo-coupling reaction of aryl Grignard reagents and its application for the synthesis of an integrin inhibitor

  • Kazuyuki Sato,
  • Satoki Teranishi,
  • Atsushi Sakaue,
  • Yukiko Karuo,
  • Atsushi Tarui,
  • Kentaro Kawai,
  • Hiroyuki Takeda,
  • Tatsuo Kinashi and
  • Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 1341–1347, doi:10.3762/bjoc.20.118

Graphical Abstract
  • Information Supporting Information File 98: General procedures and analytical data, including copies of 1H NMR and 13C NMR spectra. Acknowledgements We would like to thank Dr. Antal Harsányi at Euroapi Hungary for his helpful comments to improve the quality of the article.
PDF
Album
Supp Info
Full Research Paper
Published 12 Jun 2024

Synthesis of 1,2,3-triazoles containing an allomaltol moiety from substituted pyrano[2,3-d]isoxazolones via base-promoted Boulton–Katritzky rearrangement

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

Beilstein J. Org. Chem. 2024, 20, 1334–1340, doi:10.3762/bjoc.20.117

Graphical Abstract
  • hydrazones also can be utilized in the considered rearrangement. It should be mentioned that the presented reaction is the first example of a recyclization of the pyrano[2,3-d]isoxazolone core. The obtained 1,2,3-triazoles 4 are solid crystalline products, whose structures were proved by 1H, 13C NMR
  • obtained the recyclized product 6a (Scheme 6), whose structure was confirmed by 1H, 13C NMR spectroscopy, high-resolution mass spectrometry and X-ray analysis. Based on the aforementioned reaction we have synthesized a set of pyrazolylisoxazoles 6 (Scheme 7). The proposed mechanism of investigated
  • File 96: Experimental procedures, characterization data of all products, copies of 1H, 13C NMR, spectra of all new compounds, and X-ray crystallographic data. Acknowledgements The crystal structure determination was performed in the Department of Structural Studies of Zelinsky Institute of Organic
PDF
Album
Supp Info
Full Research Paper
Published 11 Jun 2024
Graphical Abstract
  • the bis structure are in equilibrium with maleamic acid precursors (Scheme 3) complicates the interpretation of their 1H and 13C NMR spectra. The existence of these precursors is clearly demonstrated by both their 1H and 13C NMR spectra (Supporting Information File 1). It should be noted that in the
  • ), 4.63 (d, J = 15.1 Hz, 1H, Hh), 4.42 (d, J = 15.1 Hz, 1H, Hi), 3.83 (d, J = 12 Hz, 1H, Hd), 3.65 (d, J = 12 Hz, 1H, He), 2.96 (d, J = 9.1 Hz, 1H, Ha), 2.84 (d, J = 9.1 Hz, 1H, Hb); 13C NMR (150 MHz, CDCl3) δ 173.10, 172.51, 137.22, 135.20, 134.83, 128.92, 127.98, 127.87, 88.79, 82.36, 50.72, 48.53
PDF
Album
Supp Info
Full Research Paper
Published 06 Jun 2024

Diameter-selective extraction of single-walled carbon nanotubes by interlocking with Cu-tethered square nanobrackets

  • Guoqing Cheng and
  • Naoki Komatsu

Beilstein J. Org. Chem. 2024, 20, 1298–1307, doi:10.3762/bjoc.20.113

Graphical Abstract
  • (Scheme 2) [11]. The products were fully characterized by 1H and 13C NMR, and MALDI-TOF mass spectroscopy (see Supporting Information File 1). The total yield of 4b (5.5%) based on 2,7-dibromopyrene is much lower than that of 4a (44%) [11], because a larger amount of the product 4b was lost in the
  • measurements and analyzed with mMass [29] software. 1H and 13C NMR spectra were recorded on JNM-ECS 400 spectrometer using the sample solutions in chloroform-d (CDCl3). Raman spectra were recorded on LabRam HR800 (Horiba Ltd.) and take the average of more than ten different spots for the final curve. UV–Vis
  • , rt, 1.5 h; iv) p-chloranil, dichloromethane, rt, 5 h. Supporting Information Supporting Information File 86: Details of theoretical calculations, experimental procedures, copies of 1H and 13C NMR spectra. Acknowledgements Computation time was provided by supercomputer system, Academic Center for
PDF
Album
Supp Info
Full Research Paper
Published 05 Jun 2024

Synthesis of indano[60]fullerene thioketone and its application in organic solar cells

  • Yong-Chang Zhai,
  • Shimon Oiwa,
  • Shinobu Aoyagi,
  • Shohei Ohno,
  • Tsubasa Mikie,
  • Jun-Zhuo Wang,
  • Hirofumi Amada,
  • Koki Yamanaka,
  • Kazuhira Miwa,
  • Naoyuki Imai,
  • Takeshi Igarashi,
  • Itaru Osaka and
  • Yutaka Matsuo

Beilstein J. Org. Chem. 2024, 20, 1270–1277, doi:10.3762/bjoc.20.109

Graphical Abstract
  • of Lawesson's reagent and the reaction temperature. The transformation from ketone to thioketone was confirmed by 13C NMR, which showed a downfield shift from 198 ppm for the carbonyl carbon to 235 ppm for the thiocarbonyl carbon. With the optimized conditions (Table 1, entry 9) in hand, different
PDF
Album
Supp Info
Letter
Published 31 May 2024

Competing electrophilic substitution and oxidative polymerization of arylamines with selenium dioxide

  • Vishnu Selladurai and
  • Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2024, 20, 1221–1235, doi:10.3762/bjoc.20.105

Graphical Abstract
  • + Na]+, [2M + Na]+, and [3M + Na]+. Spectroscopic data of this compound, including FTIR as well as 1H and 13C NMR, matched those reported earlier [54]. Relative extent of polymerization To compare the relative polymerization tendency, we conducted reactions of arylamines with SeO2 in acetonitrile in
  • account. Characterization of the organoselenium compounds by HRMS, 1H, and 13C NMR was supported by 77Se NMR and single-crystal X-ray analysis in order to confirm the identity of the compounds. Experimental General procedures All syntheses were carried out using the standard Schlenk line in a nitrogen
  • environment. Acetonitrile (99.9%) was bought from Avra Chemicals Private Ltd. and used without any further purification. Selenium dioxide and a range of reactants were purchased from Sigma-Aldrich. TLC was performed using silica-gel-coated aluminum sheets (TLC silica gel 60 F254). 1H, 13C, and 77Se NMR (500
PDF
Album
Supp Info
Full Research Paper
Published 27 May 2024

Introduction of peripheral nitrogen atoms to cyclo-meta-phenylenes

  • Koki Ikemoto and
  • Hiroyuki Isobe

Beilstein J. Org. Chem. 2024, 20, 1207–1212, doi:10.3762/bjoc.20.103

Graphical Abstract
  • total, 3a was obtained in 7% yield (325 mg, 0.707 mmol). N3-[6]CMP (3a): 1H NMR (CDCl3, 600 MHz) δ 9.05 (d, J = 2.1 Hz, 6H), 8.58 (t, J = 2.1 Hz, 3H), 8.23 (t, J = 2.1 Hz, 3H), 7.89 (dd, J = 7.6, 2.1 Hz, 6H), 7.69 (t, J = 7.6 Hz, 3H); 13C NMR (CDCl3, 150 MHz) δ 146.6 (CH), 138.3, 135.7, 133.9 (CH
  • ), 130.2 (CH), 127.5 (CH), 125.9 (CH); HRMS (APCI) (m/z): [M + H]+ calcd. for C33H22N3, 460.1808; found, 460.1808. N4-[8]CMP (3b): 1H NMR (CDCl3, 600 MHz) δ 8.81 (d, J = 1.4 Hz, 8H), 8.13 (t, J = 1.4 Hz, 4H), 7.76 (s, 4H), 7.66–7.73 (m, 12H); 13C NMR (CDCl3, 150 MHz) δ 147.9 (CH), 139.2, 137.0, 133.5 (CH
PDF
Album
Supp Info
Letter
Published 24 May 2024

Two-fold addition reaction of silylene to C60: structural and electronic properties of a bis-adduct

  • Masahiro Kako,
  • Masato Kai,
  • Masanori Yasui,
  • Michio Yamada,
  • Yutaka Maeda and
  • Takeshi Akasaka

Beilstein J. Org. Chem. 2024, 20, 1179–1188, doi:10.3762/bjoc.20.100

Graphical Abstract
  • ). In the 13C NMR spectrum, a total of 43 signals were observed in the low-field region (approximately 160–120 ppm), of which 29 signals are attributed to the C60 carbon cage and 14 signals are attributed to the aromatic ring carbon nuclei of the Dip groups (Figure 4). In addition, three sp3 carbon
  • . Reagents were used as purchased unless otherwise specified. The 1H and 13C NMR measurements were conducted on a JEOL ECA-500 spectrometer (JEOL Ltd.). Absorption spectra were measured using a UV-3150 spectrophotometer (Shimadzu Corp.). Cyclic voltammograms and differential pulse voltammograms were recorded
  • Hz, 6H), 1.371 (d, J = 7.0 Hz, 6H), 1.365 (d, J = 7.0 Hz, 6H), 1.31 (d, J = 7.0 Hz, 6H), 1.29 (d, J = 7.0 Hz, 6H), 1.17 (d, J = 7.0 Hz, 6H), 1.06 (d, J = 7.0 Hz, 6H); 13C NMR (CDCl3/CS2 3:1) δ 160.16 (s, 2C), 158.38 (s, 2C), 158.33 (s, 2C), 158.29 (s, 2C), 158.18 (s, 2C), 157.12 (s, 2C), 155.78 (s
PDF
Album
Supp Info
Full Research Paper
Published 22 May 2024

Bismuth(III) triflate: an economical and environmentally friendly catalyst for the Nazarov reaction

  • Manoel T. Rodrigues Jr.,
  • Aline S. B. de Oliveira,
  • Ralph C. Gomes,
  • Amanda Soares Hirata,
  • Lucas A. Zeoly,
  • Hugo Santos,
  • João Arantes,
  • Catarina Sofia Mateus Reis-Silva,
  • João Agostinho Machado-Neto,
  • Leticia Veras Costa-Lotufo and
  • Fernando Coelho

Beilstein J. Org. Chem. 2024, 20, 1167–1178, doi:10.3762/bjoc.20.99

Graphical Abstract
  • reactivity of 9dc,dl. Supporting Information Supporting Information File 26: Experimental section and copies of 1H and 13C NMR spectra of all new compounds. Funding The authors thank the São Paulo Foundation Science (FAPESP, #2018/02611-0, #2013/07600-3 and #2023/18007-3, to FC) for financial support. F. C
PDF
Album
Supp Info
Full Research Paper
Published 21 May 2024
Graphical Abstract
  • spectroscopy. After 51 hours of reaction in boiling CH2Cl2, Diels–Alder adduct 27 was observed in 22% yield. Compound 27 was identified by 1H NMR and 13C NMR spectroscopies as well as high-resolution ESI mass spectrometry. Although the lack of reactivity observed for 3 and 23 limited our kinetic analysis, we
  • modified cardboard box were utilized for detection of TLC spots. Melting points were determined in open capillary tubes using a Mel-Temp apparatus, and are uncorrected. Proton nuclear magnetic resonance (1H NMR) spectra and carbon nuclear magnetic resonance (13C NMR) spectra were recorded on either a
  • , washed with 5 mL water, and then air dried to give 3 as a white solid (57 mg, 60%, Scheme 3). Mp 169–170 °C (from [13], 188–189 °C); 1H NMR (500 MHz, CDCl3) δ 7.15–7.08 (m, 2H), 6.98 (s, 4H), 6.86–6.79 (m, 2H), 2.35 (s, 6H), 2.12 (s, 12H); 13C NMR (126 MHz, CDCl3) δ 143.54, 139.17, 138.71, 128.23, 127.43
PDF
Album
Supp Info
Full Research Paper
Published 17 May 2024

Synthesis of 1,4-azaphosphinine nucleosides and evaluation as inhibitors of human cytidine deaminase and APOBEC3A

  • Maksim V. Kvach,
  • Stefan Harjes,
  • Harikrishnan M. Kurup,
  • Geoffrey B. Jameson,
  • Elena Harjes and
  • Vyacheslav V. Filichev

Beilstein J. Org. Chem. 2024, 20, 1088–1098, doi:10.3762/bjoc.20.96

Graphical Abstract
  • anomers with a α/β ratio of 2:1, as determined by 1H and 13C NMR. Deprotected nucleosides Va and Vb but not Vc exhibited absorbance in the UV region with ε258 = 4230 L⋅mol−1⋅cm−1 and ε262 = 4730 L⋅mol−1⋅cm−1, respectively. This was most likely a result of the presence of a double bond next to the P=O unit
  • the enzymatic assays and the synthesis of nucleosides and modified ODNs, assignment of 1H, 13C, 31P NMR and IR spectra and results of HRESIMS experiments for new compounds synthesised as well as RP-HPLC profiles and HRESIMS spectra of ODNs. Acknowledgements NMR and mass spectrometry facilities at
PDF
Album
Supp Info
Full Research Paper
Published 15 May 2024

Mild and efficient synthesis and base-promoted rearrangement of novel isoxazolo[4,5-b]pyridines

  • Vladislav V. Nikol’skiy,
  • Mikhail E. Minyaev,
  • Maxim A. Bastrakov and
  • Alexey M. Starosotnikov

Beilstein J. Org. Chem. 2024, 20, 1069–1075, doi:10.3762/bjoc.20.94

Graphical Abstract
  • inhibitor of homeodomain-interacting protein kinases (HIPKs) [32], and combretastatin A-4 analogs evaluated for their anticancer properties against a panel of 60 human cancer cell lines [33] (Figure 2). The structures of all new compounds were confirmed by 1H and 13C NMR and HRMS. X-ray diffraction studies
  • were performed for compounds 12c and 13c,d (Figure 3; see Supporting Information File 1 for details) that allowed us to unambiguously establish the structures of both the starting hydrazones and rearrangement products. Conclusion In summary, we have developed an efficient method for the synthesis of
  • molecule is not shown), 13c (top right), and 13d (bottom) with thermal ellipsoids set at a 50% probability level. Intermolecular hydrogen bonds are drawn with dashed lines. Methods for the synthesis of isoxazolo[4,5-b]pyridines: (A) annulation of an isoxazole fragment to a pyridine ring; (B) annulation of
PDF
Album
Supp Info
Full Research Paper
Published 14 May 2024

Structure–property relationships in dicyanopyrazinoquinoxalines and their hydrogen-bonding-capable dihydropyrazinoquinoxalinedione derivatives

  • Tural N. Akhmedov,
  • Ajeet Kumar,
  • Daken J. Starkenburg,
  • Kyle J. Chesney,
  • Khalil A. Abboud,
  • Novruz G. Akhmedov,
  • Jiangeng Xue and
  • Ronald K. Castellano

Beilstein J. Org. Chem. 2024, 20, 1037–1052, doi:10.3762/bjoc.20.92

Graphical Abstract
  • , 230−400 mesh from Whatman. Routine 300(75) MHz 1H(13C) NMR spectra were recorded on Varian Mercury 300 or Gemini 300 spectrometers. Routine 500(125) MHz 1H(13C) NMR were recorded on an INOVA 500 spectrometer. 2D NMR spectra were recorded using a 600 MHz Varian instrument. Chemical shifts (δ) are given
  • amounts of CH2Cl2 and THF (10 mL), and dried in vacuo to afford a bright orange solid of 1a (0.264 g, 1.14 mmol, 89%). 1H NMR (600 MHz, DMSO-d6) δ 8.30–8.31 (dd, J = 3 Hz, J = 6.6 Hz, 2H), 8.49–8.51 (dd, J = 3 Hz, J = 6.6 Hz, 2H); 13C NMR (150 MHz, DMSO-d6) δ 114.5, 130.4, 136.1, 136.2, 142.7, 147.4; HRMS
  • (s, 6H), 8.27 (s, 2H); 13C NMR (125 MHz, DMSO-d6) δ 20.1, 114.2, 127.8, 134.6, 142.3, 146.6, 148.7. The proton NMR in chloroform matches the literature value [25]; HRMS (DART): [M + H]+ calcd for C14H8N6, 261.0883; found, 261.0889; [M + NH4]+, 278.1149; found, 278.1154. Aceanthryleno[1,2-b]pyrazino
PDF
Album
Supp Info
Full Research Paper
Published 08 May 2024

Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions

  • Naoki Miyamoto,
  • Daichi Koseki,
  • Kohei Sumida,
  • Elghareeb E. Elboray,
  • Naoko Takenaga,
  • Ravi Kumar and
  • Toshifumi Dohi

Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90

Graphical Abstract
  • details and copies of 1H, 13C, and 19F NMR spectra. Acknowledgements T.D. thanks for the generous gift of fluoroalcohols from Central Glass Co., Ltd. Funding N.T. and T.D. acknowledge support from JSPS KAKENHI Grant Number 20K06980 (N.T.) and 19K05466 (T.D.), JST CREST grant number JPMJCR20R1 (T.D.), and
PDF
Album
Supp Info
Letter
Published 03 May 2024

One-pot Ugi-azide and Heck reactions for the synthesis of heterocyclic systems containing tetrazole and 1,2,3,4-tetrahydroisoquinoline

  • Jiawei Niu,
  • Yuhui Wang,
  • Shenghu Yan,
  • Yue Zhang,
  • Xiaoming Ma,
  • Qiang Zhang and
  • Wei Zhang

Beilstein J. Org. Chem. 2024, 20, 912–920, doi:10.3762/bjoc.20.81

Graphical Abstract
  • and 13C NMR, and HRMS analysis. In addition, single crystals of compound 6d and 8c were obtained for X-ray analysis to confirm the structures (Figure 2). Conclusion In conclusion, we have developed a one-pot synthesis with two or three steps for making tetrazolo-pyrazino[2,1-a]isoquinolin-6(5H)-ones
PDF
Album
Supp Info
Full Research Paper
Published 23 Apr 2024
Other Beilstein-Institut Open Science Activities