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Search for "HPLC" in Full Text gives 816 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Enhanced reactivity of Li+@C60 toward thermal [2 + 2] cycloaddition by encapsulated Li+ Lewis acid

  • Hiroshi Ueno,
  • Yu Yamazaki,
  • Hiroshi Okada,
  • Fuminori Misaizu,
  • Ken Kokubo and
  • Hidehiro Sakurai

Beilstein J. Org. Chem. 2024, 20, 653–660, doi:10.3762/bjoc.20.58

Graphical Abstract
  • reactant 4, which has a larger energy gap between its HOMO and LUMO of Li+@C60 (1.92 eV). All reactions were conducted in the dark to avoid photoinduced SET reactions (Scheme 2). First, the reactivity was assessed by monitoring the reaction progress using a previously developed electrolyte-added HPLC
  • technique [25]. As expected, both substrates 1 and 2 reacted with Li+@C60 at room temperature and exhibited HPLC signals assignable to the desirable monoadducts 5a and 5b (Figure 2). It is noteworthy that the reaction of 2 proceeded faster than that of 1, although 2 has a lower HOMO level than 1. This is
  • , photoirradiation triggered the elimination of the addends, reforming the starting Li+@C60 (Figure 3). No other insoluble or undetectable products by HPLC were identified during the study. On the other hand, the reactions of 3 and 4 with Li+@C60 did not proceed significantly even under higher temperature reaction
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Published 25 Mar 2024

Isolation and structure determination of a new analog of polycavernosides from marine Okeania sp. cyanobacterium

  • Kairi Umeda,
  • Naoaki Kurisawa,
  • Ghulam Jeelani,
  • Tomoyoshi Nozaki,
  • Kiyotake Suenaga and
  • Arihiro Iwasaki

Beilstein J. Org. Chem. 2024, 20, 645–652, doi:10.3762/bjoc.20.57

Graphical Abstract
  • hexane. The aqueous MeOH portion was purified by reversed-phase column chromatography (ODS silica gel, MeOH/H2O), automated flash chromatography (hexane/EtOAc), and repeated reversed-phase HPLC to give polycavernoside E (1, 0.5 mg as a colorless oil). The isolation of compound 1 was directed by its
  • pump and a UV detector was used. HPLC analysis was conducted using a pump (model PU-2080, Jasco) and a UV detector (model UV-2075, Jasco). All chemicals and solvents used in this study were the best grade available and obtained from a commercial source (Nacalai Tesque). Collection and identification of
  • AFCS [Ø 11 × 300 mm; flow rate 5 mL/min; detection at 254 nm; solvent gradient condition, hexane/EtOAc 28:72 → 7:93] to give a fraction that contained compound 1 (17.5 mg, tR = 32.0 min). The fraction that contained 1 was further purified by HPLC [Cosmosil 5C18-MS-II (Ø 20 mm × 250 mm); solvent MeOH
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Published 21 Mar 2024

Production of non-natural 5-methylorsellinate-derived meroterpenoids in Aspergillus oryzae

  • Jia Tang,
  • Yixiang Zhang and
  • Yudai Matsuda

Beilstein J. Org. Chem. 2024, 20, 638–644, doi:10.3762/bjoc.20.56

Graphical Abstract
  • earlier. We then analyzed the metabolites from the resulting transformants using high-performance liquid chromatography (HPLC), which revealed that all of the enzymes, except AdrI, accepted 1 and produced 5-MOA-derived meroterpenoids (Figure 2B, traces iii to vii). Since the transformation plasmid with
  • : farnesyl pyrophosphate; FAD: flavin adenine dinucleotide; NADPH: nicotinamide adenine dinucleotide phosphate. (B) HPLC profiles of the metabolites from Aspergillus oryzae transformants. The chromatograms were extracted at 254 nm. (C) Structures of metabolites detected or isolated in this study. Note that
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Published 20 Mar 2024

Chemical and biosynthetic potential of Penicillium shentong XL-F41

  • Ran Zou,
  • Xin Li,
  • Xiaochen Chen,
  • Yue-Wei Guo and
  • Baofu Xu

Beilstein J. Org. Chem. 2024, 20, 597–606, doi:10.3762/bjoc.20.52

Graphical Abstract
  • , given the application of suitable activation techniques. Results and Discussion Compound isolation and structure elucidation To activate the silent BGCs in Penicillium shentong XL-F41, we conducted small-scale fermentations using various media. Analysis revealed that HPLC peaks, which correspond to
  • extract was partitioned between EtOAc and H2O. The EtOAc fraction was chromatographed repeatedly over silica gel and reversed-phase high-performance liquid chromatography (RP-HPLC), resulting in the isolation of pure compounds 1–12 (Figure 2). According to literature reports of known compounds, some of
  • , Yantai, China, available in 100–200 and 200–300 mesh sizes. Reversed-phase HPLC analyses were conducted on an Agilent 1260 instrument equipped with a DAD detector and an Agilent ZORBAX SB-C18 column (5 µm, 4.6 × 150 mm). The solvents used for HPLC were supplied by Yantai Huisente New Material Technology
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Published 15 Mar 2024

Switchable molecular tweezers: design and applications

  • Pablo Msellem,
  • Maksym Dekthiarenko,
  • Nihal Hadj Seyd and
  • Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

Graphical Abstract
  • enantiomers (P,P) and (M,M) were separated by chiral HPLC and displayed opposite circularly polarized luminescence (CPL) and electronic circular dichroism (ECD) properties. The addition of ZnCl2 switched the system from a compact conformation to an extended conformation, resulting in a modulation of the
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Published 01 Mar 2024

A new analog of dihydroxybenzoic acid from Saccharopolyspora sp. KR21-0001

  • Rattiya Janthanom,
  • Yuta Kikuchi,
  • Hiroki Kanto,
  • Tomoyasu Hirose,
  • Arisu Tahara,
  • Takahiro Ishii,
  • Arinthip Thamchaipenet and
  • Yuki Inahashi

Beilstein J. Org. Chem. 2024, 20, 497–503, doi:10.3762/bjoc.20.44

Graphical Abstract
  • preparative HPLC of the crude extract, 7.9 mg of 1 was obtained (Scheme 1). Table S1 (Supporting Information File 1) shows the physicochemical properties of 1, which is a yellow oil soluble in MeOH and DMSO. The UV absorption maximum of 1 was at 286 nm (ε = 10238 M−1·cm−1). The molecular formula of 1 was
  • %, 40%, 50%, 60%, 80%, and 100%) with 0.05% FA. The 20% fraction was purified by HPLC (Shimadzu, Columbia, MD, U.S.A.) with an ODS column (Pegasil ODS SP100, 20 i.d. × 250 mm) at a flow rate of 7 mL·min−1 and eluted with 20% MeOH with 0.05% FA (Scheme 1). The fraction with a retention time of 64.5 min
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Published 29 Feb 2024

Pseudallenes A and B, new sulfur-containing ovalicin sesquiterpenoid derivatives with antimicrobial activity from the deep-sea cold seep sediment-derived fungus Pseudallescheria boydii CS-793

  • Zhen Ying,
  • Xiao-Ming Li,
  • Sui-Qun Yang,
  • Hong-Lei Li,
  • Xin Li,
  • Bin-Gui Wang and
  • Ling-Hong Meng

Beilstein J. Org. Chem. 2024, 20, 470–478, doi:10.3762/bjoc.20.42

Graphical Abstract
  • LH-20, and semi-preparative HPLC, yielded compounds 1–5 (Figure 1). Structure elucidations Pseudallene A (1), initially obtained as colorless amorphous powder, was assigned a molecular formula of C16H28O5S with three indices of hydrogen deficiency according to the HRESIMS data. The 1H NMR spectrum
  • using solvent chemical shifts (DMSO: δH/δC 2.50/39.52) as reference. HRESIMS data were measured using an API QSTAR Pulsar 1 mass spectrometer. HPLC was performed on a Dionex HPLC system equipped with a P680 pump, an ASI-100 automated sample injector, and a UVD340U multiple-wavelength detector controlled
  • semipreparative HPLC (Elite ODSBP column, 5 μm; 10 × 250 mm; 75% MeOH/H2O, 3 mL/min) from Fr. 4.3 (5.8 g). Fr. 5 (6.5 g) was further fractionated by CC over Lobar LiChroprep RP-18 eluting with a MeOH/H2O gradient (from 1:9 to 10:0) to yield 10 subfractions (Frs. 5.1–5.10). Fr. 5.3 (258 mg) was further purified by
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Published 28 Feb 2024

Discovery of unguisin J, a new cyclic peptide from Aspergillus heteromorphus CBS 117.55, and phylogeny-based bioinformatic analysis of UngA NRPS domains

  • Sharmila Neupane,
  • Marcelo Rodrigues de Amorim and
  • Elizabeth Skellam

Beilstein J. Org. Chem. 2024, 20, 321–330, doi:10.3762/bjoc.20.32

Graphical Abstract
  • . heteromorphus CBS 117.55 on rice solid medium yielded an organic-soluble extract, which was subjected to fractionation using preparative HPLC-PDA-ELSD and purification by semipreparative HPLC-PDA; this led to the isolation of a new cyclic peptide 1, along with unguisin B (2, Figure 2). The structure of the new
  • . Analytical HPLC-PDA-MS system was a Shimadzu instrument (LC2030C 3D Plus Prominence) coupled to a Shimadzu LCMS-2020 mass spectrometer. Analyses were performed using a Phenomenex Kinetex RP18 column (100 mm × 4.6 mm i.d., 2.6 μm) along with the Security Guard RP18 protective guard column (4.6 mm i.d.) and
  • . The CH3CN fraction was evaporated, yielding 0.601 g of soluble-organic extract. Fractionation and isolation of unguisins J and B The soluble-organic extract was fractionated by preparative HPLC-PDA using Kinetex RP18 column (250 mm × 30 mm i.d., 5 μm) and UV detector at λmax = 254 nm. The mobile phase
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Published 19 Feb 2024

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

  • Aissam Okba,
  • Pablo Simón Marqués,
  • Kyohei Matsuo,
  • Naoki Aratani,
  • Hiroko Yamada,
  • Gwénaël Rapenne and
  • Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

Graphical Abstract
  • stability. Conversely, selenepine 28c and selenepine Se-oxide 29c were quantitatively converted into the seco-HBC 31 by thermal activation at 200 °C for 5 min, as evidenced by UV–visible absorption and HPLC monitoring. SO-extrusion from thiepine S-oxide 29b was also successfully triggered in the solid state
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Published 15 Feb 2024

Unveiling the regioselectivity of rhodium(I)-catalyzed [2 + 2 + 2] cycloaddition reactions for open-cage C70 production

  • Cristina Castanyer,
  • Anna Pla-Quintana,
  • Anna Roglans,
  • Albert Artigas and
  • Miquel Solà

Beilstein J. Org. Chem. 2024, 20, 272–279, doi:10.3762/bjoc.20.28

Graphical Abstract
  • heating at 90 °C for 4 hours. The crude reaction mass obtained with these conditions was then purified by column chromatography (toluene). After eluting unreacted pristine C70, a dark reddish fraction was isolated and analyzed by HPLC. A major peak was observed at a retention time of 17.5 minutes, which
  • was also observed in the HPLC chromatogram, whose UV–vis has a pattern that is similar to a previously reported α-adduct [49]. We reasoned that this minor compound was the cyclohexadiene-fused C70 intermediate, analogous to cyclohexadiene-fused C60 I (see Scheme 1), which had not completely evolved
  • were found to be the same, showing that 90 °C is sufficient for the reaction to proceed. In contrast, on extending the reaction time to 24 hours, the minor peak in the HPLC disappeared and only the peak corresponding to the bis(fulleroid) remained. The yield of derivative 2a was 45%. Other experiments
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Published 13 Feb 2024

Photochromic derivatives of indigo: historical overview of development, challenges and applications

  • Gökhan Kaplan,
  • Zeynel Seferoğlu and
  • Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

Graphical Abstract
  • isomerization and photochemical (only for 13a) isomerization [46]. Compounds 13 showed intrinsic planar chirality and their enantiomers could be separated by HPLC. Notably, upon thermal and photochemical isomerization of these compounds, no Z-isomers were detected and only the racemization took place. Such
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Published 07 Feb 2024

Optimizations of lipid II synthesis: an essential glycolipid precursor in bacterial cell wall synthesis and a validated antibiotic target

  • Milandip Karak,
  • Cian R. Cloonan,
  • Brad R. Baker,
  • Rachel V. K. Cochrane and
  • Stephen A. Cochrane

Beilstein J. Org. Chem. 2024, 20, 220–227, doi:10.3762/bjoc.20.22

Graphical Abstract
  • Supporting Information File 1 for comprehensive information on the synthesis details of the tetrapeptide). To avoid loss of valuable material through HPLC purification, crude 7 is used directly in the next step, and purification performed after the final prenyl phosphate coupling and global deprotection
  • % (from compound 7) following reversed-phase HPLC purification (Scheme 2). Similarly, farnesyl, geranylgeranyl, and solanesyl-lipid II analogues 8–10 were synthesized with overall yields of 13%, 21%, and 11%, respectively, using the corresponding prenyl phosphates (Scheme 2). Conclusion In conclusion, we
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Published 06 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
  • spectroscopy and the ee values were determined by chiral HPLC. Structures of bioactive fluorinated indole derivatives. Proposed mechanism for the transfer hydrogenation reaction. Synthesis of chiral indolines via asymmetric reduction. Substrate scope of 3,3-difluoro-3H-indoles. Experiment at 2 mmol scale
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Published 01 Feb 2024
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  • in TCBDs and DCNQs and their optical resolutions were first realized in 2010 through their conjugation with methylated fullerenes, as shown in Figure 2 [130]. The optical resolution was realized using a chiral high-performance liquid chromatography (HPLC) system equipped with an (S,S)-WHELK-O1 column
  • when the TCBD moiety was incorporated at the axial position of the subphthalocyanine (SubPc) core (Figure 3) [131]. Axially chiral SubPc–TCBD–aniline conjugates 59 and 60 were characterized via optical-resolution analysis through chiral HPLC using a Chiralpak IC column. The researchers unequivocally
  • types of subporphyrin derivatives 61 and 62, wherein the subporphyrin skeleton was functionalized at its meso or axial position with the TCBD moiety (Figure 3). Although the optical resolution of 61 failed, they succeeded in achieving the optical resolution of 62 via chiral HPLC using a Chiralpak IC
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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
  • Cary 50 UV–vis spectrophotometer scanning between 800 and 200 nm. All spectra were recorded with baseline correction in CH2Cl2 or toluene (HPLC grades) at 25 °C in a quartz cuvette with a 10 mm path length. Electrochemistry Cyclic voltammograms (CV) and differential pulse voltammograms (DPV) were
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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
  • a linear gradient of chloroform/methanol. Fractions containing compound 6 were concentrated by evaporation. The residual materials were desorbed in 1 mL DMSO and applied to a reversed-phase high-performance liquid chromatography (HPLC, Shimadzu Corp.) equipped with a COSMOCORE Packed column 5C18-AR
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Published 02 Jan 2024

Long oligodeoxynucleotides: chemical synthesis, isolation via catching-by-polymerization, verification via sequencing, and gene expression demonstration

  • Yipeng Yin,
  • Reed Arneson,
  • Alexander Apostle,
  • Adikari M. D. N. Eriyagama,
  • Komal Chillar,
  • Emma Burke,
  • Martina Jahfetson,
  • Yinan Yuan and
  • Shiyue Fang

Beilstein J. Org. Chem. 2023, 19, 1957–1965, doi:10.3762/bjoc.19.146

Graphical Abstract
  • -length sequence 3 contains a polymerizable methacrylamide group at its 5'-end; the failure sequences 4 and many other impurities do not. In principle, due to the large relatively hydrophobic tag introduced by 2, the full-length sequence could be isolated by RP HPLC. However, we found that this is
  • impossible [20]. Once the length of ODNs reaches about 100-mer, RP HPLC could not resolve the full-length and failure sequences. Therefore, to isolate the full-length sequence, the catching-by-polymerization (CBP) method was employed (step 2, Figure 1, and Scheme 1). To the crude ODN, the polymerization
  •  1). Because depurination is less likely for deprotected ODNs, and the conditions are widely used for detritylation after RP HPLC, ODN damage in this step is unlikely or negligible. The purified ODNs, 399 and 401 nt, were each extracted from their gel. To remove residual acetic acid, the ODNs were
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Published 21 Dec 2023

Anion–π catalysis on carbon allotropes

  • M. Ángeles Gutiérrez López,
  • Mei-Ling Tan,
  • Giacomo Renno,
  • Augustina Jozeliūnaitė,
  • J. Jonathan Nué-Martinez,
  • Javier Lopez-Andarias,
  • Naomi Sakai and
  • Stefan Matile

Beilstein J. Org. Chem. 2023, 19, 1881–1894, doi:10.3762/bjoc.19.140

Graphical Abstract
  • OEEFs (Figure 9B). To elaborate on these great expectations, pristine MWCNTs 3 were drop casted on the graphite anodes of electrochemical microfluidic reactors [44]. The substrate was injected by a syringe pump, the product was collected at the other end of the microflow channel and analyzed by HPLC
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Published 12 Dec 2023

Controlling the reactivity of La@C82 by reduction: reaction of the La@C82 anion with alkyl halide with high regioselectivity

  • Yutaka Maeda,
  • Saeka Akita,
  • Mitsuaki Suzuki,
  • Michio Yamada,
  • Takeshi Akasaka,
  • Kaoru Kobayashi and
  • Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

Graphical Abstract
  • °C for 2 h (Scheme 1). Figure 1 depicts the changes in the visible–near infrared (vis–NIR) absorption spectra during the reaction, showing gradual changes with isosbestic points. Since the electrolyte interferes with the high-performance liquid chromatography (HPLC) separation and anionic species may
  • not be eluted under typical fullerene HPLC separation conditions, trifluoroacetic acid was added to the reaction mixture. Notably, La@C2v-C82 is produced after the addition of trifluoroacetic acid to the La@C2v-C82 anion [20]. After removing the solvent under vacuum, the electrolyte was removed by
  • adding CS2 and then filtering. Subsequent HPLC separation of the reaction mixture with 1a afforded products 2a, 3a, 4a, and 5a in yields of 40, 37, 9, and 1%, respectively, based on the consumption of La@C2v-C82 (Figure 2a and Supporting Information File 1, Figure S1). The yield was estimated from the
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Published 11 Dec 2023

Thienothiophene-based organic light-emitting diode: synthesis, photophysical properties and application

  • Recep Isci and
  • Turan Ozturk

Beilstein J. Org. Chem. 2023, 19, 1849–1857, doi:10.3762/bjoc.19.137

Graphical Abstract
  • ), dimesitylboronfluoride (90%, Sigma-Aldrich), 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (Sigma-Aldrich), tetrakis(triphenylphosphine)palladium(0) (Pd(PPh3)4, 99%, Sigma-Aldrich), were used as received. Diethyl ether and THF were dried over metallic sodium. Dimethylformamide (HPLC grade) was stored over activated molecular
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Published 07 Dec 2023

GlAIcomics: a deep neural network classifier for spectroscopy-augmented mass spectrometric glycans data

  • Thomas Barillot,
  • Baptiste Schindler,
  • Baptiste Moge,
  • Elisa Fadda,
  • Franck Lépine and
  • Isabelle Compagnon

Beilstein J. Org. Chem. 2023, 19, 1825–1831, doi:10.3762/bjoc.19.134

Graphical Abstract
  • spectroscopic fingerprints database. In MS–IR experiments, the IR data as well as the mass of the molecule are simultaneously acquired, therefore the mass could readily be used as a prefilter. More generally, all experimental data obtained in a glycomics workflow – such as MS/MS; HPLC; ion mobility; … – could
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Published 05 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
  • and high-performance liquid chromatography–mass spectrometry (HPLC–MS). The solvent ratios of the eluents are given in volume units (mL mL−1). Nuclear magnetic resonance (NMR) spectra were recorded on a Bruker DRX-500 Avance spectrometer (at 500 and 126 MHz for the 1H and 13C spectra, respectively) or
  • ionization. HPLC–MS was performed on an HPLC system using a Shimadzu LCMS-2020 (Shimadzu Corp., Japan) device equipped with a Reprospher (Altmann Analytik Corp., Germany) 100 Å C18 (5 µm; 100 × 3 mm) column and a positive/negative double ion source with a quadrupole MS analyzer in the range of 50–1000 m/z
  • . Further details are available in Supporting Information File 1. The enantiomeric ratios of the samples were determined by chiral high-performance liquid chromatography (HPLC) measurements. The exact conditions of chiral HPLC are indicated in the experimental section of the corresponding compound
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Published 24 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

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  • electrospray ionization HRESIMS analysis, and quantum chemical electronic CD calculations. Furthermore, the absolute configurations of sugar residues were determined by derivatization of the hydrolysates with ʟ-cysteine methyl ester and o-tolyl isothiocyanate followed by HPLC analysis. The anti-inflammatory
  • by acid hydrolysis of 1 using the method developed by Tanaka et al. [16], in which the hydrolysates are derivatized with ʟ-cysteine methyl ester and o-tolyl isothiocyanate followed by HPLC analysis. For compound 1, peaks were observed at retention times of 13.96, 20.83, and 22.16 min. The peaks at
  • ], these differences indicate that the sulfoxide moieties in the aglycone of 1 and 2 are isomers. The remaining NMR resonances (Table 2) and 2D NMR spectroscopic data (Figure 2) showed that the glycosyl group of 2 was the same as that of 1. This assignment was further supported by HPLC-based monosaccharide
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Published 19 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

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  • cameroonensis, isolated from the root of Trema guineensis, a Cameroonian medicinal plant from the family Ulmaceae [11]. Results Structural elucidation Diaporthe cameroonensis, which showed an interesting high-performance liquid chromatography–diode array detector–high-resolution mass spectrometry (HPLC–DAD–HRMS
  • ) 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
  • . Key COSY and HMBC correlations for 2 are illustrated in Figure 2 and the complete assignment for all protons and carbons is tabulated in Table 1. As we have been able to detect the compound by HPLC–MS in methanolic crude extracts of the fungus that did not come into contact with ethyl acetate or
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Published 13 Oct 2023

Acetaldehyde in the Enders triple cascade reaction via acetaldehyde dimethyl acetal

  • Alessandro Brusa,
  • Debora Iapadre,
  • Maria Edith Casacchia,
  • Alessio Carioscia,
  • Giuliana Giorgianni,
  • Giandomenico Magagnano,
  • Fabio Pesciaioli and
  • Armando Carlone

Beilstein J. Org. Chem. 2023, 19, 1243–1250, doi:10.3762/bjoc.19.92

Graphical Abstract
  • %) were added to a solution of 1 (10 mol %) in 2 mL of solvent (0.25 M) and allowed to stir for 48 hours at room temperature. Yields of isolated compounds are given. Diastereomeric ratio (dr) determined by 1H NMR analysis. Enatiomeric excess (ee) determined by chiral HPLC analysis. Original triple
  • : Experimental part, NMR and HPLC spectra. Funding Fabio Pesciaioli thanks the Ministero dell'Università e della Ricerca (PON-AIM1842894, CUPE18D19000560001) for funding this research. Maria Edith Casacchia thanks the support of the Italian national inter-university Ph.D. course in Sustainable Development and
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Published 24 Aug 2023
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