Search results

Search for "silica gel" in Full Text gives 1106 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

  • Periklis X. Kolagkis,
  • Eirini M. Galathri and
  • Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

Graphical Abstract
  • acids, such as N-bromosuccinimide (NBS) [54], silica chloride [55], Ph3CCl [56], ZnO [57], La(NO3)3·6H2O [58], V(HSO4)3 [59], Cu(ClO4)2·6H2O [60], Fe/Al pillared clay [61], trimethylsilyl chloride (TMSCl) [62], BiCl3-loaded montmorillonite K10 [63][64][65][66][67], ZrO2-MgO [68] or CaO [69]. Silica gel
PDF
Album
Review
Published 22 Feb 2024

Additive-controlled chemoselective inter-/intramolecular hydroamination via electrochemical PCET process

  • Kazuhiro Okamoto,
  • Naoki Shida and
  • Mahito Atobe

Beilstein J. Org. Chem. 2024, 20, 264–271, doi:10.3762/bjoc.20.27

Graphical Abstract
  • of 5 mA (3 F/mol, 57.9 C) through the CF anode (1 × 1 cm) and the Pt cathode (1 × 1 cm). The reaction mixture was concentrated in vacuo and Et2O (20 mL) was added. The resulting precipitate was removed by filtration through a short silica gel pad under reduced pressure. The filtrate was concentrated
  • was removed by filtration through a short silica gel pad under reduced pressure. The filtrate was concentrated in vacuo and the resulting residue was subjected to 1H NMR spectroscopy or column chromatography. Application of amidyl radical species generated by PCET. (A) Effect of phosphate base on the
PDF
Album
Supp Info
Full Research Paper
Published 12 Feb 2024

Chiral phosphoric acid-catalyzed transfer hydrogenation of 3,3-difluoro-3H-indoles

  • Yumei Wang,
  • Guangzhu Wang,
  • Yanping Zhu and
  • Kaiwu Dong

Beilstein J. Org. Chem. 2024, 20, 205–211, doi:10.3762/bjoc.20.20

Graphical Abstract
  • and the reaction mixture was stirred at room temperature for 3 h. After concentrating the mixture, the residue was purified by column chromatography on silica gel using a mixture of petroleum ether/ethyl acetate 30:1 (v/v) as the eluent to afford products 2. The yields were determined by 19F NMR
PDF
Album
Supp Info
Letter
Published 01 Feb 2024

Comparison of glycosyl donors: a supramer approach

  • Anna V. Orlova,
  • Nelly N. Malysheva,
  • Maria V. Panova,
  • Nikita M. Podvalnyy,
  • Michael G. Medvedev and
  • Leonid O. Kononov

Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18

Graphical Abstract
  • the stereoselectivity of sialylation, it is important to analyze anomeric ratio values (α/β) for the disaccharide fraction separated by size-exclusion chromatography since the retention values of different disaccharide anomers on silica gel may be surprisingly large and a minor isomer may be lost
  • during purification by silica gel chromatography. On the other hand, NMR analysis of the crude reaction mixtures may be misleading due to possible overlap of the signals of H-3eq belonging both to disaccharide and monosaccharide derivatives sometimes present in such glycosylation mixtures. At low
  • glycosylation reactions was distilled under argon over P2O5 and then over CaH2 and stored over molecular sieves (MS) 3 Å. Powdered MS 3 Å (Fluka) were activated before the reactions by heating at ≈220 °C in high vacuum for 6 h. Column chromatography was performed on silica gel 60 (40–63 μm, Merck). Gel
PDF
Album
Supp Info
Full Research Paper
Published 31 Jan 2024

Synthesis of the 3’-O-sulfated TF antigen with a TEG-N3 linker for glycodendrimersomes preparation to study lectin binding

  • Mark Reihill,
  • Hanyue Ma,
  • Dennis Bengtsson and
  • Stefan Oscarson

Beilstein J. Org. Chem. 2024, 20, 173–180, doi:10.3762/bjoc.20.17

Graphical Abstract
  • silica gel 60 F254. Visualisation was performed with UV-light (254 nm) fluorescence quenching, and/or by staining with an 8% H2SO4 dip (stock solution: 8 mL conc. H2SO4, 92 mL EtOH), ninhydrin dip (stock solution: 0.3 g ninhydrin, 3 mL AcOH, 100 mL EtOH) and/or ceric ammonium molybdate dip (stock
  • solution: 25 g ammonium molybdate tetrahydrate, 0.5 g Ce(SO4)2, 50 mL H2SO4, 450 mL EtOH). Chromatography Silica gel flash chromatography was carried out using Davisil® LC60A (40–63 μm) silica gel or with automated flash chromatography systems, Buchi Reveleris® X2 (UV 200–500 nm and ELSD detection
  • Celite® and concentrated in vacuo. The resulting residue was taken up in EtOAc (700 mL) and washed with 10% aq Na2S2O3 (700 mL), water (700 mL) and brine (700 mL). The organic phase was then dried over MgSO4, filtered and reduced to dryness. Flash chromatography on silica gel (toluene→toluene/EtOAc, 3:2
PDF
Album
Supp Info
Full Research Paper
Published 30 Jan 2024
Graphical Abstract
  • ) affords 7 with 16% yield, 8 with 25% yield, and 9 with 46% yield. Furthermore, 7 and 8 are efficiently converted into 10 and 11, respectively, with high yields (80% and 95%, respectively) via column chromatography employing silica gel in acetonitrile, thereby instigating further molecular transformation
  • surfactant, Brij 30, was used as the reaction solvent at a concentration of 20 mM, exceeding the critical micelle concentration, 4 and 37 were obtained in a ratio of 53:47, with 64% yield. Notably, 37 exhibits instability in silica gel and polar solvents. In particular, when 37 is kept in ethyl acetate or
PDF
Album
Review
Published 22 Jan 2024

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

  • Christina Schøttler,
  • Kasper Lund-Rasmussen,
  • Line Broløs,
  • Philip Vinterberg,
  • Ema Bazikova,
  • Viktor B. R. Pedersen and
  • Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

Graphical Abstract
  • molecular sieves, or by drying over 3 Å molecular sieves. All remaining anhydrous solvents were obtained from a solvent drying tower (IT model PS-MD-05). HPLC grade solvents were used unless otherwise specified. Purification by chromatography was performed using silica gel (flash: 40–63 μm, Sepacore® Flash
  • Systems X10/X50: 40–63 μm). TLC was performed using aluminum sheets covered with silica gel coated with fluorescent indicator. NMR spectra were recorded on a Bruker instrument at 500 MHz and 126 MHz for 1H and 13C NMR, respectively. Deuterated chloroform (CDCl3, 1H = 7.26 ppm, 13C = 77.16 ppm), deuterated
PDF
Album
Supp Info
Full Research Paper
Published 15 Jan 2024

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

  • Seiji Kawai,
  • Akito Yamada,
  • Yohei Katsuyama and
  • Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

Graphical Abstract
  • (15 mg/L) was added to the culture, and the culture was continued for another 1 day. The pH was adjusted to 4 by adding 6 M HCl to the culture, and the metabolites were extracted by ethyl acetate. After the ethyl acetate was evaporated, the metabolites were absorbed for 5.0 g silica gel 60 (0.040
  • –0.063 mm, Merck Millipore, Burlington, MA, USA). The silica gel holding the metabolites was applied to a normal-phase medium-pressure liquid chromatography system (MPLC, Shoko Scientific, Kanagawa, Japan) equipped with a silica column (Purif-Pack, Shoko Scientific), and the metabolites were eluted with
PDF
Album
Supp Info
Full Research Paper
Published 02 Jan 2024

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

  • Karolis Leitonas,
  • Brigita Vigante,
  • Dmytro Volyniuk,
  • Audrius Bucinskas,
  • Pavels Dimitrijevs,
  • Sindija Lapcinska,
  • Pavel Arsenyan and
  • Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

Graphical Abstract
  • purification. Thin-layer chromatography (TLC) was performed using Merck Silica gel 60 F254 plates and visualized by UV (254 nm) fluorescence. Zeochem silica gel (ZEOprep 60/35–70 microns – SI23501) was used for column chromatography. 1H and 13C NMR spectra were recorded on a Bruker 400 spectrometer at 400 and
  • for 1 h. After cooling, the reaction was quenched by the addition of ice and the precipitate was filtered off. The crude product was purified by flash chromatography on silica gel using chloroform as eluent yielding compound 3 (1.0 g, 78%) as white powder. Mp > 200 °C; 1H NMR (400 MHz, DMSO-d6) 7.91
  • dried over Na2SO4. After the solvent was removed, the crude yellow product was carefully washed twice with acetonitrile to remove the starting materials. Further purification was achieved using flash chromatography on silica gel (eluent: dichloromethane/petroleum ether 1:2). Compound 4 (0.86 g, 61%) was
PDF
Album
Supp Info
Full Research Paper
Published 12 Dec 2023

Substituent-controlled construction of A4B2-hexaphyrins and A3B-porphyrins: a mechanistic evaluation

  • Seda Cinar,
  • Dilek Isik Tasgin and
  • Canan Unaleroglu

Beilstein J. Org. Chem. 2023, 19, 1832–1840, doi:10.3762/bjoc.19.135

Graphical Abstract
  • , Kieselgel 60, F254, Merck) with visualization under UV light. Products were purified by silica gel flash column chromatography (0.05–0.63 mm, 230–400 mesh ASTM, E.Merck). N-Tosylimines 2a–m and 5,10-bis(pentafluorophenyl)tripyrromethane (1) were synthesized according to the previously reported literature
  • )tripyrromethane (1, 0.090 mmol) in CH2Cl2 (1.5 mL) and the mixture was stirred at rt for 4 h. Afterwards, DDQ (0.180 mmol) was added to this solution and stirred for another 2 h. The resulting solution was eluted through a short silica gel column with EtOAc and the solvent was removed under reduced pressure. The
  • residue was purified by silica gel column chromatography (EtOAc/hexane 1:50) or preparative thin-layer chromatography on silica gel (Silica gel 60, F254, Merck) where applicable to obtain A3B-porphyrins and A4B2-hexaphyrins. Yields of porphyrins 3a–k were between 9–22% and the yields of hexaphyrins 4b–g,j
PDF
Album
Supp Info
Full Research Paper
Published 06 Dec 2023

A novel recyclable organocatalyst for the gram-scale enantioselective synthesis of (S)-baclofen

  • Gyula Dargó,
  • Dóra Erdélyi,
  • Balázs Molnár,
  • Péter Kisszékelyi,
  • Zsófia Garádi and
  • József Kupai

Beilstein J. Org. Chem. 2023, 19, 1811–1824, doi:10.3762/bjoc.19.133

Graphical Abstract
  • achieved, for example, by immobilizing the catalysts to a solid support [15], e.g., silica gel [16][17][18], organic polymers [19][20][21], magnetic nanoparticles [22][23], or by membrane separation, e.g., using organic solvent nanofiltration (OSN) [24][25][26], which methods can be easily implemented in
  • menthol. The reactions under pressure were carried out in a 150 mL pressure flask (Synthware Glass). Thin-layer chromatography (TLC) was performed using silica gel 60 F254 (Merck) plates. The spots of the materials on TLC plates were visualized by UV light at 254 nm. The reactions were monitored by TLC
PDF
Album
Supp Info
Full Research Paper
Published 24 Nov 2023

Active-metal template clipping synthesis of novel [2]rotaxanes

  • Cătălin C. Anghel,
  • Teodor A. Cucuiet,
  • Niculina D. Hădade and
  • Ion Grosu

Beilstein J. Org. Chem. 2023, 19, 1776–1784, doi:10.3762/bjoc.19.130

Graphical Abstract
  • experimental data Commercially available reagents were used without further purification. Compounds 1 [43][47], 4 [48], 9 [49], 10 [44] and M2 [44] were synthesized according to procedures reported in the literature. Thin-layer chromatography (TLC) was performed on silica gel 60 coated aluminium F254 plates
  • and visualized by UV irradiation at 254 nm. Preparative column chromatography was carried out using silica gel 60 (0.040–0.063 mm) from Merck. The NMR spectra were recorded on Bruker Avance 400 MHz or Bruker Avance 600 MHz spectrometers. Chemical shifts (δ) are reported in parts per million (ppm
PDF
Album
Supp Info
Full Research Paper
Published 20 Nov 2023

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

  • Suangsiri Arunlimsawat,
  • Patteera Funchien,
  • Pongsakorn Chasing,
  • Atthapon Saenubol,
  • Taweesak Sudyoadsuk and
  • Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

Graphical Abstract
  • chromatography over silica gel eluting with CH2Cl2/hexane 1:4 to give white solids (2.11 g, 87%). 1H NMR (600 MHz, CDCl3) δ 8.12 (d, J = 7.7 Hz, 2H), 7.40 (t, J = 7.8 Hz, 2H), 7.34 (d, J = 8.2 Hz, 2H), 7.28 (t, J = 8.0 Hz, 4H), 7.24 (d, J = 8.1 Hz, 2H), 7.21–7.07 (m, 15H); 13C NMR (151 MHz, CDCl3) δ 143.55
  • was washed with water, brine, dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure. The crude product was then purified by column chromatography over silica gel eluting with CH2Cl2/hexane 3:7 to give compound 3 as white solid (928 mg, 41% over two steps). 1H NMR (600 MHz
  • purified by column chromatography over silica gel eluting with CH2Cl2/hexane 3:7, followed by recrystallization from a CH2Cl2/methanol mixture to obtain TPECNz as red solid (396.0 mg, 58%). Mp > 360 °C; 1H NMR (600 MHz, CDCl3) δ 8.43 (s, 2H), 8.15 (td, J = 7.1, 3.5 Hz, 4H), 7.74 (dd, J = 8.3, 1.7 Hz, 2H
PDF
Album
Supp Info
Full Research Paper
Published 03 Nov 2023

Sulfur-containing spiroketals from Breynia disticha and evaluations of their anti-inflammatory effect

  • Ken-ichi Nakashima,
  • Naohito Abe,
  • Masayoshi Oyama,
  • Hiroko Murata and
  • Makoto Inoue

Beilstein J. Org. Chem. 2023, 19, 1604–1614, doi:10.3762/bjoc.19.117

Graphical Abstract
  • using an Agilent 6230 LC/TOF mass spectrometer. HPLC was performed on a Hitachi HPLC system equipped with an L-2130 pump, an L-2200 autosampler, an L-2300 column oven, and an L-2455 diode array detector. Silica gel AP-300 (Toyota Kako), Sephadex LH-20 (GE Healthcare), and Cosmosil 75C18-OPN (Nacalai
  • Tesque) were used for column chromatography (CC). Silica gel 60 F254 and RP-18 F254S (Merck) were used for TLC analysis. Plant material B. disticha was cultivated in the greenhouse of Setsunan University medicinal plant garden (Osaka, Japan) in September 2014. Taxonomic identification was performed by an
  • were concentrated in vacuo to yield the ethyl acetate fraction (11.8 g) and n-butanol fraction (7.4 g), respectively. The ethyl acetate fraction was separated by silica gel CC with CHCl3/MeOH (stepwise gradient of 100:1, 50:1, 30:1, 20:1, 15:1, 10:1, 8:1, and 0:1, v/v) as the eluent. The fractions were
PDF
Album
Supp Info
Full Research Paper
Published 19 Oct 2023

Lewis acid-promoted direct synthesis of isoxazole derivatives

  • Dengxu Qiu,
  • Chenhui Jiang,
  • Pan Gao and
  • Yu Yuan

Beilstein J. Org. Chem. 2023, 19, 1562–1567, doi:10.3762/bjoc.19.113

Graphical Abstract
  • TLC monitoring. Upon completion, the solution was cooled to room temperature and the solvent was removed under vacuum directly. The crude residue was purified by column chromatography on silica gel (ethyl acetate/petroleum ether 40:1) to afford product 3a with 87% yield. Natural products and drug
PDF
Album
Supp Info
Full Research Paper
Published 16 Oct 2023

Secondary metabolites of Diaporthe cameroonensis, isolated from the Cameroonian medicinal plant Trema guineensis

  • Bel Youssouf G. Mountessou,
  • Élodie Gisèle M. Anoumedem,
  • Blondelle M. Kemkuignou,
  • Yasmina Marin-Felix,
  • Frank Surup,
  • Marc Stadler and
  • Simeon F. Kouam

Beilstein J. Org. Chem. 2023, 19, 1555–1561, doi:10.3762/bjoc.19.112

Graphical Abstract
  • ) profile, was scale up fermented to give 12 g of culture extract. This extract was subjected to a silica gel column chromatography to give several fractions, which were further purified over normal and reversed-phase HPLC to yield 2-ethyl-2,6-dihydroxy-5,7-dimethylbenzofuran-3-one (1), 3,9
  • . Experimental General experimental procedures Column chromatography (60.4 cm length × 5.5 cm inner diameter) was carried out on silica gel 230–400 mesh (Merck). Analytical TLC was performed on Merck pre-coated silica gel 60 F254 plates, and spots were detected using ceric sulfate spray reagent and/or diluted
  • of this extract was subjected to a silica gel (230–400 mesh) column chromatography using a stepwise gradient of CH2Cl2/MeOH (ranging from 0 to 100% of MeOH, v/v), to afford a total of 8 main series (A–H) obtained on the basis of TLC analyses. However, series A (2.5 g) obtained with pure CH2Cl2 and
PDF
Album
Supp Info
Full Research Paper
Published 13 Oct 2023

Functions of enzyme domains in 2-methylisoborneol biosynthesis and enzymatic synthesis of non-natural analogs

  • Binbin Gu,
  • Lin-Fu Liang and
  • Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1452–1459, doi:10.3762/bjoc.19.104

Graphical Abstract
  • chromatography was performed using silica gel 60 (0.040–0.060 nm) purchased from Merck (Darmstadt, Germany). NMR spectra were recorded on a Bruker Avance I 500 MHz spectrometer and a Bruker Avance III HD 700 MHz Cryo spectrometer. Chemical shifts were referenced to the residual proton signal of C6D6 (δ = 7.16
PDF
Album
Supp Info
Letter
Published 22 Sep 2023

α-(Aminomethyl)acrylates as acceptors in radical–polar crossover 1,4-additions of dialkylzincs: insights into enolate formation and trapping

  • Angel Palillero-Cisneros,
  • Paola G. Gordillo-Guerra,
  • Fernando García-Alvarez,
  • Olivier Jackowski,
  • Franck Ferreira,
  • Fabrice Chemla,
  • Joel L. Terán and
  • Alejandro Perez-Luna

Beilstein J. Org. Chem. 2023, 19, 1443–1451, doi:10.3762/bjoc.19.103

Graphical Abstract
  • reduced pressure to provide the crude product which was then purified by column chromatography on silica gel. 2. Procedure for the air-promoted 1,4-addition of dialkylzinc reagents to α-(aminomethyl)acrylates (preparation of compounds 11–13, 14a–c, and 15a). In a Schlenk-tube under argon, the appropriate
  • (MgSO4), and concentrated under reduced pressure to provide the crude product which was then purified by column chromatography on silica gel. 3. Procedure for the air-promoted tandem 1,4-addition–aldol reaction between dialkylzinc reagents, α-(aminomethyl)acrylates and carbonyl derivatives (preparation
  • aq NH4Cl (5 mL) at 0 °C. The aqueous layer was extracted with CH2Cl2 (2×). The combined organic layer was washed (brine), dried (MgSO4), and concentrated under reduced pressure to provide the crude product which was then purified by column chromatography on silica gel. Air-promoted radical chain
PDF
Album
Supp Info
Full Research Paper
Published 21 Sep 2023

Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

  • Nadia Ledermann,
  • Alae-Eddine Moubsit and
  • Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

Graphical Abstract
  • removed under vacuo. The residue was purified by chromatography on silica gel (n-hexane/ethyl acetate 100:1 to 5:1) to give pure compound 5d (243 mg, 69%) as a beige solid. Mp 118.2 °C; Rf 0.50 (n-hexane/ethyl acetate 10:1); 1H NMR (600 MHz, CDCl3) δ 3.68 (s, 3H), 7.02–7.07 (m, 1H), 7.17–7.20 (m, 1H
  • organic phases were dried with anhydrous sodium sulfate, filtered, and the solvent was removed under reduced pressure. The residue was purified by chromatography on silica gel (n-hexane/ethyl acetate 20:1 to 5:1) to give compound 6 (184 mg, 42%) as a colorless solid. Mp 204.5 °C; Rf 0.35 (n-hexane/ethyl
  • combined organic phases were dried (anhydrous sodium sulfate), filtered, and the solvent was removed under vacuo. The residue was purified by chromatography on silica gel (n-hexane/ethyl acetate 20:1 to 5:1) to give compound 8b (105 mg, 71%) as a colorless solid. Mp 150.8 °C (lit.: 157 °C [38]); Rf 0.58 (n
PDF
Album
Supp Info
Full Research Paper
Published 14 Sep 2023

Visible-light-induced nickel-catalyzed α-hydroxytrifluoroethylation of alkyl carboxylic acids: Access to trifluoromethyl alkyl acyloins

  • Feng Chen,
  • Xiu-Hua Xu,
  • Zeng-Hao Chen,
  • Yue Chen and
  • Feng-Ling Qing

Beilstein J. Org. Chem. 2023, 19, 1372–1378, doi:10.3762/bjoc.19.98

Graphical Abstract
  • LEDs (λmax = 399 nm) for 7 h. After the reaction was complete, the reaction mixture was poured into water and extracted with EtOAc. The combined organic phase was separated and washed with brine, dried over Na2SO4, and concentrated under vacuum. The resulting residue was purified by silica gel flash
PDF
Album
Supp Info
Full Research Paper
Published 11 Sep 2023

Synthesis of ether lipids: natural compounds and analogues

  • Marco Antônio G. B. Gomes,
  • Alicia Bauduin,
  • Chloé Le Roux,
  • Romain Fouinneteau,
  • Wilfried Berthe,
  • Mathieu Berchel,
  • Hélène Couthon and
  • Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

Graphical Abstract
  • alcohol. This step was achieved by the deprotonation of 21.3 followed by the reaction with 1-bromooctadecane. Compound 21.4 was purified by chromatography on silica gel followed by a recrystallization in acetone. Deprotonation of the secondary alcohol present in 21.4 followed by the addition of
PDF
Album
Review
Published 08 Sep 2023

Metal catalyst-free N-allylation/alkylation of imidazole and benzimidazole with Morita–Baylis–Hillman (MBH) alcohols and acetates

  • Olfa Mhasni,
  • Jalloul Bouajila and
  • Farhat Rezgui

Beilstein J. Org. Chem. 2023, 19, 1251–1258, doi:10.3762/bjoc.19.93

Graphical Abstract
  • under reflux (for 5a) or in a Dean–Stark apparatus (for 4a). After completion (TLC), the reaction mixture was cooled, washed with brine, and dried. The toluene was removed and the residue was purified by column chromatography on silica gel (acetone/ether 8:2) to give the pure N-substituted imidazole 6a
  • mL) was added. The mixture was washed with brine and dried. Finally, the solvent was removed and the residue was purified by column chromatography on silica gel, using acetone/ether as eluent, to give the pure imidazole derivative 8. Medicines containing an imidazole nucleus. Synthesis of N
PDF
Album
Supp Info
Full Research Paper
Published 01 Sep 2023

Unravelling a trichloroacetic acid-catalyzed cascade access to benzo[f]chromeno[2,3-h]quinoxalinoporphyrins

  • Chandra Sekhar Tekuri,
  • Pargat Singh and
  • Mahendra Nath

Beilstein J. Org. Chem. 2023, 19, 1216–1224, doi:10.3762/bjoc.19.89

Graphical Abstract
  • on silica gel 60 F254 (pre-coated aluminium) sheets from Merck. General procedure for the synthesis of copper(II) benzo[f]chromeno[2,3-h]quinoxalinoporphyrins 3–8 To a solution of copper(II) 2,3-diamino-meso-tetraarylporphyrin (1; 0.131 mmol) in chloroform (20 mL), 2-hydroxynaphthalene-1,4-dione (2
PDF
Album
Supp Info
Full Research Paper
Published 11 Aug 2023

The effect of dark states on the intersystem crossing and thermally activated delayed fluorescence of naphthalimide-phenothiazine dyads

  • Liyuan Cao,
  • Xi Liu,
  • Xue Zhang,
  • Jianzhang Zhao,
  • Fabiao Yu and
  • Yan Wan

Beilstein J. Org. Chem. 2023, 19, 1028–1046, doi:10.3762/bjoc.19.79

Graphical Abstract
  • chromatography (silica gel, DCM/PE 1:5, v:v). Compound NI-PTZ-F was obtained as orange solid. Yield: 40 mg (15%); mp 136.2–137.2 °C; 1H NMR (CDCl3, 400 MHz) δ 8.87 (d, J = 7.63 Hz, 1H), 8.70 (d, J = 7.25 Hz, 1H), 8.60 (d, J = 8.51 Hz, 1H), 8.00 (d, J = 7.63 Hz, 1H), 7.77–7.81 (m, 1H), 7.29–7.35 (m, 4H), 7.11 (d
  • . Synthesis of NI-PTZ-Ph NI-PTZ-Ph was synthesized by a reported method [11][71] similar to that of NI-PTZ-F. The crude product was purified by column chromatography (silica gel, DCM/PE 1:3, v:v). Compound NI-PTZ-Ph was obtained as orange solid. Yield: 243 mg (52%); mp 126.2–127.2 °C; 1H NMR (CDCl3, 400 MHz
  • product was purified by column chromatography (silica gel, DCM/PE 1:3, v:v). The product was obtained as orange solid. Yield: 230 mg (80%); mp 100.2–101.5 °C; 1H NMR (CDCl3, 400 MHz) δ 8.87 (d, J = 7.63 Hz, 1H), 8.69 (d, J = 8.38 Hz, 1H), 8.58 (d, J = 8.50 Hz, 1H), 7.98 (d, J = 7.76 Hz, 1H), 7.75–7.79 (m
PDF
Album
Supp Info
Full Research Paper
Published 19 Jul 2023

Five new sesquiterpenoids from agarwood of Aquilaria sinensis

  • Hong Zhou,
  • Xu-Yang Li,
  • Hong-Bin Fang,
  • He-Zhong Jiang and
  • Yong-Xian Cheng

Beilstein J. Org. Chem. 2023, 19, 998–1007, doi:10.3762/bjoc.19.75

Graphical Abstract
  • methods were used to purify the extract, such as MCI gel CHP 20, silica gel column, vacuum liquid chromatography, and semi-preparative HPLC purification, to obtain pure compounds. A total of ten compounds, including five new eudesmane-type sesquiterpenoids (1–5), and five known compounds were identified
  • isolated by other researchers in the future, who could consider our conclusions and choose other aspects of biological activity to study. Experimental General procedures NMR spectra were recorded on a Bruker AV-500 or AV-600 spectrometer with TMS as an internal standard. Silica gel (200–300 mesh; Qingdao
  • Marine Chemical Inc., Qingdao, China), RP-18 silica gel (40–60 µm; Daiso Co., Tokyo, Japan), and MCI gel CHP 20P (75–150 µm, Mitsubishi Chemical Industries, Tokyo, Japan) were used for column chromatography. Optical rotations were measured on an Anton Paar MCP-100 digital polarimeter. UV and CD spectra
PDF
Album
Supp Info
Full Research Paper
Published 30 Jun 2023
Other Beilstein-Institut Open Science Activities