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Search for "chromatography" in Full Text gives 1901 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Domino reactions of chromones with activated carbonyl compounds

  • Peter Langer

Beilstein J. Org. Chem. 2024, 20, 1256–1269, doi:10.3762/bjoc.20.108

Graphical Abstract
  • dienes has to proceed with full conversion and in high yield as the they cannot be purified by chromatography. Distillation is also problematic, as dienes containing substituents located at carbon atom C-2 readily undergo isomerization reactions. The reactions of 1,3-bis(silyloxy)-1,3-butadienes with
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Published 29 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
  • oxidative polymerization in the presence of SeO2. After recognizing the polymeric nature of the solid, we analyzed the small molecular species present in the supernatant. Thin-layer chromatography (TLC) of the supernatant revealed that it contained a mixture of compounds. We could not isolate monoselenide 1
  • as a pure compound through column chromatography. The obtained fraction was a black solid as reported by Bhat et al., and HRMS analysis revealed a peak at m/z 265.0229, corresponding to [M + H]+ (Figure S4, Supporting Information File 1). However, we could not ascertain the identity of the compound
  • methyl anthranilate with SeO2 (vide infra), which was also supported by single-crystal X-ray analysis. However, for aniline, in addition to the major polymerization and poor selenation process, solvent oxidation was also noted. Importantly, through column chromatography, the oxamide derivative 3 formed
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Published 27 May 2024

Cofactor-independent C–C bond cleavage reactions catalyzed by the AlpJ family of oxygenases in atypical angucycline biosynthesis

  • Jinmin Gao,
  • Liyuan Li,
  • Shijie Shen,
  • Guomin Ai,
  • Bin Wang,
  • Fang Guo,
  • Tongjian Yang,
  • Hui Han,
  • Zhengren Xu,
  • Guohui Pan and
  • Keqiang Fan

Beilstein J. Org. Chem. 2024, 20, 1198–1206, doi:10.3762/bjoc.20.102

Graphical Abstract
  • -morpholino)propanesulfonic acid (MOPS) buffer (pH 7.5), and the cells were disrupted by ultrasonication to obtain the cell extract. Cell debris was removed by centrifugation (14,000g, 15 min). The proteins were purified by Ni-NTA agarose chromatography, desalted, and concentrated by centrifugation (8,000g
  • , 30 min) in 10 kDa ultrafiltration tubes (Centriplus YM series, Merck Millipore). Protein concentration was quantified by the Bradford method. AlpJ, JadG, JadH, and E. coli flavin reductase (Fre) were overproduced and purified by Ni-NTA agarose chromatography as described previously [10][11][43][44
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Published 23 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
  • accompanied by mono-adduct 2 (22% yield) by silica gel flash column chromatography using mixed solvents of hexane/CH2Cl2 by changing the ratios of volumes from 10:1 to 3:1. In thin-layer chromatography (TLC) analysis using silica gel, the Rf values are 0.55 for 2 and 0.33 for 3, respectively, with hexane
  • column chromatography (SiO2) using mixed solvents of hexane/CH2Cl2 by changing the ratios of volumes from 10:1 to 3:1. TLC analysis (SiO2, hexane/CH2Cl2 5:1) afforded Rf = 0.55 for 2 and Rf = 0.33 for 3, respectively. Data for compound 3: 1H NMR (CDCl3/CS2 3:1) δ 7.61 (t, J = 7.5 Hz, 1H), 7.56 (t, J
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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
  • yields. For derivatives 9af,ag,bq, we observed the formation of an E/Z mixture of products that was inseparable by column chromatography. Synthesis of 3-aryl-2-ethoxycarbonyl-1-indanones and 3-aryl-1-indanones With the starting materials prepared, we began evaluating the use of bismuth salts to promote
  • different compounds containing the indanone moiety. Synthesis of unsaturated β-ketoesters (Knoevenagel derivatives). aIsolated yield after purification using silica gel column chromatography. Synthesis of 3-aryl-2-ethoxycarbonyl-1-indanones mediated by bismuth triflate. aIsolated yield after purification
  • using silica gel column chromatography. bExtensive degradation. cRecovery of starting material. Basic protocol: The Knoevenagel product 9 (0.5 mmol), dry acetonitrile (2 mL), and Bi(OTf)3 (0.05 mmol) were added to a sealed tube. The reaction mixture was stirred at 60 °C and monitored by TLC. Controlled
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Published 21 May 2024
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  • obtained using a solvent purification system (Innovative Technologies, Inc.) and handled under a nitrogen atmosphere, unless otherwise noted. Flash chromatography was performed using SiliaFlash® F60 40–63 µm (230–400 mesh) 60 Å silica from Silicycle Inc. and RediSep® Rf Silica Flash Columns (12 g, 24 g or
  • 40 g) on a CombiFlash® Rf 200 instrument (Teledyne Isco, Inc.). Evaporation of solvents was accomplished using an IKA® RV 10 digital rotary evaporator. Baker-flex® silica gel IB2-F thin-layer chromatography (TLC) plates were purchased from J.T. Baker. A 4 watt 254 nm lamp (Analtytik Jena Co.) and a
  • gel CombiFlash chromatography (hexane/EtOAc 9:1) to obtain 22 as a yellow solid (0.44 g, 35%, Scheme 5). Mp 59–60 °C; 1H NMR (500 MHz, CDCl3) δ 7.43 (s, 4H), 6.93 (s, 4H), 2.64 (q, J = 7.6 Hz, 4H), 2.53 (q, J = 7.5 Hz, 8H), 1.25 (t, J = 7.6 Hz, 6H), 1.08 (t, J = 7.5 Hz, 12H); 13C NMR (126 MHz, CDCl3
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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
  • /Et3N, followed by silica gel column chromatography, led to the triethylammonium salt of 2-N-Boc-aminoethylphosphinic acid 5 in 50 % yield. Alkylation of acid 5 with methyl chloroacetate in the presence of TMSCl and Et3N took five days at room temperature, and compound 6 as triethylammonium salt was
  • phosphinic acid 7 was further protected with benzyl alcohol by a procedure adopted from reference [67] using TBTU and Et3N in refluxing dichloroethane. Compound 8 was obtained in 65% yield after silica gel column chromatography. To synthesise a nucleobase for nucleosides Va and Vb, we first obtained
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Published 15 May 2024

Light on the sustainable preparation of aryl-cored dibromides

  • Fabrizio Roncaglia,
  • Alberto Ughetti,
  • Nicola Porcelli,
  • Biagio Anderlini,
  • Andrea Severini and
  • Luca Rigamonti

Beilstein J. Org. Chem. 2024, 20, 1076–1087, doi:10.3762/bjoc.20.95

Graphical Abstract
  • the addition was complete, the mixture was left under stirring for 1 h and 30 min. After the workup, operated as described previously, a brown slurry was obtained. Yield: 42%. The crude product was purified via column chromatography on silica gel 60, eluting with petroleum ether. The pure product
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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
  • . Palladium(II) acetate and anhydrous 1,4-dioxane were purchased from Strem Chemicals or Sigma-Aldrich and used as received. Thin-layer chromatography (TLC) was performed on SiO2-60 F254 aluminum plates with visualization by UV light or staining. Flash column chromatography was performed using Purasil SiO2-60
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Published 08 May 2024

A Diels–Alder probe for discovery of natural products containing furan moieties

  • Alyssa S. Eggly,
  • Namuunzul Otgontseren,
  • Carson B. Roberts,
  • Amir Y. Alwali,
  • Haylie E. Hennigan and
  • Elizabeth I. Parkinson

Beilstein J. Org. Chem. 2024, 20, 1001–1010, doi:10.3762/bjoc.20.88

Graphical Abstract
  • easily identifiable on liquid chromatography–mass spectrometry (LC–MS). The molecular probe, which undergoes this reaction with a variety of furans, was designed with both a UV-tag and a mass tag to enable easy identification. The probe has been tested with a variety of purified furans, including natural
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Published 02 May 2024

Enantioselective synthesis of β-aryl-γ-lactam derivatives via Heck–Matsuda desymmetrization of N-protected 2,5-dihydro-1H-pyrroles

  • Arnaldo G. de Oliveira Jr.,
  • Martí F. Wang,
  • Rafaela C. Carmona,
  • Danilo M. Lustosa,
  • Sergei A. Gorbatov and
  • Carlos R. D. Correia

Beilstein J. Org. Chem. 2024, 20, 940–949, doi:10.3762/bjoc.20.84

Graphical Abstract
  • two runs. Enantiomeric ratios (er) were determined by high-performance liquid chromatography (HPLC) analysis of the purified compounds. Heck–Matsuda reaction of N-tosyl-2,5-dihydro-1H-pyrrole (1b). Reaction conditions: 1) pyrroline 1b (0.30 mmol, 1.0 equiv), aryldiazonium salts 2 (0.60 mmol, 2.0 equiv
  • chromatography (HPLC) analysis of the purified compounds. Heck–Matsuda reaction of the protected 2,5-dihydro-1H-pyrrole with Ns and 2-Ns groups (pyrrolines 1c, 1d). Reaction conditions: 1) pyrroline 1c or 1d (0.30 mmol, 1.0 equiv), aryldiazonium salts 2 (0.60 mmol, 2.0 equiv), Pd(TFA)2 (5 mol %), L1 (6 mol
  • %), ZnCO3 (0.15 mmol, 0.5 equiv), MeOH (1.5 mL, 0.2 M), 40 °C, 4 h. 2) 1.0 mL Jones solution 2.5 M, 6 mL of acetone/water 3:1 (v/v), 1.5 h. Isolated yields were calculated from an average of two runs. Enantiomeric ratio (er) determined by high-performance liquid chromatography (HPLC) analysis of the
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Published 29 Apr 2024

Direct synthesis of acyl fluorides from carboxylic acids using benzothiazolium reagents

  • Lilian M. Maas,
  • Alex Haswell,
  • Rory Hughes and
  • Matthew N. Hopkinson

Beilstein J. Org. Chem. 2024, 20, 921–930, doi:10.3762/bjoc.20.82

Graphical Abstract
  • of the desired amide 5a after 16 h at rt, which could be isolated in 80% yield after column chromatography. A survey of carboxylic acids 1 revealed that the one-pot approach is efficient for a variety of substitution profiles (Scheme 2). Aromatic acids bearing methyl substituents at the para-, ortho
  • the optimised one-pot conditions with benzylamine (4a) resulted in the formation of the desired amide product, however, significant by-products were also observed. Careful column chromatography of the crude reaction mixture allowed for the partial isolation and characterisation of the
  • benzothiazolium species would avoid the formation of thiocarbonyl difluoride, which is most likely responsible for the generation of thiourea 7. Pleasingly, under these conditions, amide 5s was formed smoothly with isolation by column chromatography providing the pure product in 71% yield (Scheme 3b). Furthermore
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Published 23 Apr 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
  • the reported procedures [41], the Ugi-azide reaction of 2-bromobenzaldehyde (1a, 1 mmol), allylamine hydrochloride (2, 1 mmol), trimethylsilyl azide (3, 1 mmol) and tert-butyl isocyanide (4a, 1 mmol) in MeOH at 40 °C for 24 h afforded 1,5-DS-1H-T 5a in 92% yield after chromatography purification. Our
  • at 40 °C for 24 h in a sealed vial. Upon completion of the reaction, the reaction mixture was filtered and evaporated under vacuum to give crude products 5a. Further purification was conducted by flash chromatography with 1:6 petroleum ether/EtOAc to afford 5a in 92% yields. The adduct was confirmed
  • was purified by flash chromatography with 1:4 ethyl acetate/petroleum ether to afford product 6a. General procedure for the one-pot synthesis of tetrazole-containing 1,2,3,4-tetrahydroisoquinolines 6 A mixture of 2-bromobenzaldehyde 1 (1 mmol), allylamine hydrochloride (2, 1 mmol), trimethylsilyl
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Published 23 Apr 2024

Synthesis and properties of 6-alkynyl-5-aryluracils

  • Ruben Manuel Figueira de Abreu,
  • Till Brockmann,
  • Alexander Villinger,
  • Peter Ehlers and
  • Peter Langer

Beilstein J. Org. Chem. 2024, 20, 898–911, doi:10.3762/bjoc.20.80

Graphical Abstract
  • performed on a Bruker Apex Kappa-II CCD diffractometer. The solvents used, dimethyl sulfoxide and 1,4-dioxane, were purchased as dry solvents and applied without further purification. Other reagents, catalysts, ligands, acids, and bases were used as purchased from commercial suppliers. Column chromatography
  • was performed on Merck Silica gel 60 (particle size 63–200 μm). Solvents for extraction and column chromatography were distilled prior employment. Representative method for the preparation of starting materials 5-Bromo-6-chloro-1,3-dimethyluracil (2). Uracil 1 (22.9 mmol; 4.00 g) was dissolved in
  • by column chromatography (heptane/ethyl acetate). Representative procedure B for the synthesis of 4a–j. A mixture of 2 (402 µmol; 102 mg), Pd(CH3CN)2Cl2 (5 mol %; 23 µmol; 6 mg), CuI (5 mol %; 21 µmol; 4 mg) was dissolved in 1,4-dioxane (5 mL) and stirred for 5 min under an argon atmosphere. NEt3 (11
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Published 22 Apr 2024

(Bio)isosteres of ortho- and meta-substituted benzenes

  • H. Erik Diepers and
  • Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

Graphical Abstract
  • intramolecular crossed [2 + 2] cycloaddition strategy (Scheme 4C) [36]. They were able to avoid purification by column chromatography by transformation of BCH ester (±)-53 into BCH acid (±)-54, allowing isolation of pure 1,2-BCH (±)-54 by crystallisation. Through their synthesis they were able to access both
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Published 19 Apr 2024

Activity assays of NnlA homologs suggest the natural product N-nitroglycine is degraded by diverse bacteria

  • Kara A. Strickland,
  • Brenda Martinez Rodriguez,
  • Ashley A. Holland,
  • Shelby Wagner,
  • Michelle Luna-Alva,
  • David E. Graham and
  • Jonathan D. Caranto

Beilstein J. Org. Chem. 2024, 20, 830–840, doi:10.3762/bjoc.20.75

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  • homologs to Vs NnlA, each homolog was recombinantly expressed in E. coli and purified. One of the five homologs, Pj NnlA, was found to be substantially insoluble and thus, could not be isolated. The remaining four homologs were isolated by immobilized metal affinity chromatography. While the most prominent
  • contaminants but are either undissociated higher oligomer states or are oligomers whose formation is induced by SDS treatment, which has been observed for other proteins [29][30]. To characterize these oligomer states of native protein, analytical size exclusion chromatography data were collected (Figure 2B
  • pET-28a(+)-TEV by GenScript. For protein expression, plasmids were electroporated into E. coli BL21(DE3) cells and protein was expressed and purified by immobilized metal affinity chromatography (IMAC) as previously described for Vs NnlA [21]. The only modification was that plasmids using pET-28a
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Published 17 Apr 2024

Skeletal rearrangement of 6,8-dioxabicyclo[3.2.1]octan-4-ols promoted by thionyl chloride or Appel conditions

  • Martyn Jevric,
  • Julian Klepp,
  • Johannes Puschnig,
  • Oscar Lamb,
  • Christopher J. Sumby and
  • Ben W. Greatrex

Beilstein J. Org. Chem. 2024, 20, 823–829, doi:10.3762/bjoc.20.74

Graphical Abstract
  • mixture of ketone 9e and the O-alkylated enol ether by-product, which was then reduced using NaBH4 to give alcohol 10e with 98:2 selectivity. Similarly, the reaction of 4-methoxybenzyl bromide and 2 gave ketone 9f in 35% yield without chromatography, and when reduced resulted in only a single alcohol
  • chiral auxiliary 10a, and following a survey of conditions and isolation protocols, a 90% yield was obtained when 10a was heated in the presence of 2 equivalents of SOCl2 and 5 equivalents of pyridine in DCE. Flash chromatography of the chloroalkyl ether 11a resulted in significant loss due to hydrolysis
  • sulfites were not intermediates in the reaction manifold. Furthermore, the isolation of some starting alcohols in the reactions of 10b and 10d following chromatography was attributed to hydrolysis of the corresponding dialkyl sulfite 13b and 13d on silica, a process that can be acid or base-catalysed [26
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Published 16 Apr 2024

Advancements in hydrochlorination of alkenes

  • Daniel S. Müller

Beilstein J. Org. Chem. 2024, 20, 787–814, doi:10.3762/bjoc.20.72

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  • , yielding 4 with 90% yield and 99% conversion. A drawback of the Rolla protocol is the cost associated with the phase-transfer catalyst, and that the crude mixture requires purification through distillation or column chromatography. Another inconvenience is the high reaction temperature which limits the
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Published 15 Apr 2024

Synthesis of new representatives of A3B-type carboranylporphyrins based on meso-tetra(pentafluorophenyl)porphyrin transformations

  • Victoria M. Alpatova,
  • Evgeny G. Rys,
  • Elena G. Kononova and
  • Valentina A. Ol'shevskaya

Beilstein J. Org. Chem. 2024, 20, 767–776, doi:10.3762/bjoc.20.70

Graphical Abstract
  • temperature for 4 h. Under these reaction conditions, monoazide derivative 2 was obtained in 40% yield along with a mixture of porphyrin 1, di- and triazido-substituted derivatives. The reaction mixture was separated by column chromatography on SiO2 using CH2Cl2/hexane 2:8 as an eluent. The reduction of the
  • temperature under argon. Under these reaction conditions, the tris(carboranyl)-substituted porphyrin 6 was obtained in 39% yield after purification by column chromatography on SiO2 using CHCl3/hexane 1:1 as eluent (Scheme 3). It should be noted that the reaction of porphyrin 6 with NaN3 in DMSO at 20 °C for
  • 48 h resulted in a mixture of azidoporphyrin 7 and amino derivative 5 which were separated by column chromatography on SiO2 to give porphyrin 7 and porphyrin 5 in 66% and 33% yields, respectively. The reduction of porphyrin 7 with SnCl2·2H2O in MeOH afforded porphyrin 5 in 92% yield. We investigated
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Published 12 Apr 2024

Substrate specificity of a ketosynthase domain involved in bacillaene biosynthesis

  • Zhiyong Yin and
  • Jeroen S. Dickschat

Beilstein J. Org. Chem. 2024, 20, 734–740, doi:10.3762/bjoc.20.67

Graphical Abstract
  • His-tagged enzyme was obtained through heterologous expression and purification by Ni2+-NTA affinity chromatography (Figure S1, Supporting Information File 1). After incubation of the purified enzyme with the 13C-labelled SNAC derivatives (S)-11 or (R)-11 for 30 minutes at 25 °C, the incubation buffer
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Published 05 Apr 2024

Genome mining of labdane-related diterpenoids: Discovery of the two-enzyme pathway leading to (−)-sandaracopimaradiene in the fungus Arthrinium sacchari

  • Fumito Sato,
  • Terutaka Sonohara,
  • Shunta Fujiki,
  • Akihiro Sugawara,
  • Yohei Morishita,
  • Taro Ozaki and
  • Teigo Asai

Beilstein J. Org. Chem. 2024, 20, 714–720, doi:10.3762/bjoc.20.65

Graphical Abstract
  • determined to be (−)-sandaracopimaradiene (Figure 3B). We then turned our attention to the individual function of these enzymes. With this aim, AsPS and AsCPS were expressed in Escherichia coli as N-terminal hexa-histidine-tagged proteins and purified by Ni-affinity chromatography (see Supporting Information
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Published 03 Apr 2024

New variochelins from soil-isolated Variovorax sp. H002

  • Jabal Rahmat Haedar,
  • Aya Yoshimura and
  • Toshiyuki Wakimoto

Beilstein J. Org. Chem. 2024, 20, 692–700, doi:10.3762/bjoc.20.63

Graphical Abstract
  • remove salt and carbohydrate residues. After the retained siderophores were extracted with methanol, the obtained crude extract was further fractionated through several rounds of column chromatography, guided by a colorimetric-based chrome azurol sulfonate siderophore assay (CAS assay) [13], to yield
  • , which was packed into a column for chromatography. The packed resin was washed with water several times and then eluted with an excess of methanol. The collected methanol fraction was concentrated in vacuo to obtain a crude extract. Subsequently, the crude extract was subjected to Sephadex LH-20 column
  • chromatography, with methanol as the mobile phase. After monitoring the fractions by a CAS assay, the positive fractions were concentrated and purified by semi-preparative HPLC on a Cosmosil 5C18-MS-II column (10 mm ID × 250 mm, Nacalai Tesque), using a gradient system with MeCN/H2O (3:7 to 7:3) as the mobile
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Published 02 Apr 2024

Regioselective quinazoline C2 modifications through the azide–tetrazole tautomeric equilibrium

  • Dāgs Dāvis Līpiņš,
  • Andris Jeminejs,
  • Una Ušacka,
  • Anatoly Mishnev,
  • Māris Turks and
  • Irina Novosjolova

Beilstein J. Org. Chem. 2024, 20, 675–683, doi:10.3762/bjoc.20.61

Graphical Abstract
  • % conversion when 1 equivalent of sulfinate was used. Products 8 exhibited instability in the presence of water, leading to the formation of hydrolysis product 9 [25] in the reaction mixture. This instability caused issues during the reaction work-up, and attempts for purification using column chromatography
  • anhydrous THF, MeCN, and dioxane, using such azide sources as NaN3, LiN3, and TMS-N3. Full conversion towards product 12a was observed by HPLC with NaN3 in anhydrous DMF. However, precipitation, direct, and reversed-phase column chromatography provided low yields (Scheme 5) due to the degradation of the
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Published 28 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

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  • 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
  • based on HMBC and HMQC experiments. HRESIMS spectra were obtained on a Bruker timsTOF mass spectrometer. For reversed-phase column chromatography, ODS silica gel Cosmosil 75C18-OPN (Nacalai Tesque) was used. For medium pressure column chromatography, AFCS (Smart Flash AKROS, Yamazen) consisting of a
  • ). The aqueous MeOH layer was concentrated, and the obtained residue (673 mg) was separated by column chromatography on ODS (7 g) eluted with 35 mL of 40%, 60%, 80%, and 90% aqueous MeOH, followed by 35 mL of MeOH and 70 mL of CHCl3/MeOH 1:1. The fraction (244.4 mg) eluted with 80% MeOH was subjected to
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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
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Published 20 Mar 2024
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