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Search for "mass spectrometry" in Full Text gives 653 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Synthesis and physicochemical evaluation of fluorinated lipopeptide precursors of ligands for microbubble targeting

  • Masayori Hagimori,
  • Estefanía E. Mendoza-Ortega and
  • Marie Pierre Krafft

Beilstein J. Org. Chem. 2021, 17, 511–518, doi:10.3762/bjoc.17.45

Graphical Abstract
  • was stepwisely elongated, and eventually conjugated with the (perfluoroalkyl)ethyl acids (Scheme 2). After the cleavage from the resin, the Fmoc groups of the amino acids were removed, and the F-lipopeptides were purified using a dialysis membrane. According to mass spectrometry, FTIR, and HPLC
  • Information Supporting Information File 46: Mass spectrometry and FTIR data as well as RP-HPLC chromatograms of lipopeptides 1–4. Funding The work was supported by JSPS KAKENHI Grant Number JP18KK0439 and JP20K08139. We also acknowledge CONACYT (Mexico) for a Ph.D. fellowship (E.E.M.O., grant #459199).
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Published 19 Feb 2021

Unexpected rearrangements and a novel synthesis of 1,1-dichloro-1-alkenones from 1,1,1-trifluoroalkanones with aluminium trichloride

  • Beatrice Lansbergen,
  • Catherine S. Meister and
  • Michael C. McLeod

Beilstein J. Org. Chem. 2021, 17, 404–409, doi:10.3762/bjoc.17.36

Graphical Abstract
  • mass spectrometry and so it was converted to carboxylic acids 14 and 15 by the treatment with silica gel and NaOH, respectively, in order to confirm its identity. A possible mechanism for the formation of 13 from 5n could involve the formation of a terminal carbocation from trichloroalkanone 8n
  • Supporting Information File 58: Detailed experimental procedures and NMR spectra for all compounds referenced. Acknowledgements We thank Mr Martin Annau for his valuable assistance in NMR interpretation and structure elucidation, Mrs Susanne Ries for performing the mass spectrometry measurements and Dr
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Letter
Published 10 Feb 2021

Synthesis of legonmycins A and B, C(7a)-hydroxylated bacterial pyrrolizidines

  • Wilfred J. M. Lewis,
  • David M. Shaw and
  • Jeremy Robertson

Beilstein J. Org. Chem. 2021, 17, 334–342, doi:10.3762/bjoc.17.31

Graphical Abstract
  • diamond ATR module, and νmax values are expressed in cm−1. HRMS measurements were performed by the Mass Spectrometry Service at the Chemistry Research Laboratory, University of Oxford, using a Bruker microTOF spectrometer. Values of m/z are calculated to 0.0001 Daltons from the chemical formula, and all
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Published 02 Feb 2021

Regioselective chemoenzymatic syntheses of ferulate conjugates as chromogenic substrates for feruloyl esterases

  • Olga Gherbovet,
  • Fernando Ferreira,
  • Apolline Clément,
  • Mélanie Ragon,
  • Julien Durand,
  • Sophie Bozonnet,
  • Michael J. O'Donohue and
  • Régis Fauré

Beilstein J. Org. Chem. 2021, 17, 325–333, doi:10.3762/bjoc.17.30

Graphical Abstract
  • (t), doublet of doublets (dd), doublet of doublets of doublets (ddd), broad (br), and quadruplet of triplets (qt) as abbreviations. Analyses and assignments were made using 1D (1H, 13C, and J-modulated spin–echo (Jmod)) and 2D NMR experiments (COSY and HSQC). High-resolution mass spectrometry (HRMS
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Published 01 Feb 2021

19F NMR as a tool in chemical biology

  • Diana Gimenez,
  • Aoife Phelan,
  • Cormac D. Murphy and
  • Steven L. Cobb

Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28

Graphical Abstract
  • ). Each independent intermediate was characterized on the basis of its 19F NMR chemical shift and the kinetics by which each species formed or decayed were evaluated in real-time. By combining the 19F NMR data with that provided by complementary analytical techniques, mass spectrometry (electrospray
  • widely used by those investigating the biodegradation of fluorinated xenobiotics, with researchers more commonly relying on liquid or gas chromatography–mass spectrometry methods. Objectively, these techniques are much more sensitive than 19F NMR, provide more structural information and are probably more
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Published 28 Jan 2021

Direct synthesis of anomeric tetrazolyl iminosugars from sugar-derived lactams

  • Michał M. Więcław and
  • Bartłomiej Furman

Beilstein J. Org. Chem. 2021, 17, 115–123, doi:10.3762/bjoc.17.12

Graphical Abstract
  • -5-yl)-iminosugars, using 2,3,5-tri-O-benzyl-ᴅ-ribofuranose- and -arabinofuranose-derived lactams as substrates were made. Very unexpectedly, we failed to isolate such products although we did observe their formation via mass spectrometry of the reaction mixtures. Employing alternative procedures did
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Published 13 Jan 2021

Control over size, shape, and photonics of self-assembled organic nanocrystals

  • Chen Shahar,
  • Yaron Tidhar,
  • Yunmin Jung,
  • Haim Weissman,
  • Sidney R. Cohen,
  • Ronit Bitton,
  • Iddo Pinkas,
  • Gilad Haran and
  • Boris Rybtchinski

Beilstein J. Org. Chem. 2021, 17, 42–51, doi:10.3762/bjoc.17.5

Graphical Abstract
  • applicability of organic nanocrystals. Experimental General information The 1H and 13C NMR spectra were recorded at 20 °C on a 300 MHz NMR spectrometer (Bruker). Electrospray ionization (ESI) mass spectrometry was performed using a Micromass Platform instrument. UV–vis absorption and fluorescence measurements
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Published 06 Jan 2021

The fluorescence of a mercury probe based on osthol

  • Guangyan Luo,
  • Zhishu Zeng,
  • Lin Zhang,
  • Zhu Tao and
  • Qianjun Zhang

Beilstein J. Org. Chem. 2021, 17, 22–27, doi:10.3762/bjoc.17.3

Graphical Abstract
  • fluorescence, UV–vis spectrophotometry, mass spectrometry, and 1H NMR spectroscopy, and the recognition mechanism is discussed. The results showed that OST and Hg2+ can form a complex with a stoichiometric ratio of 1:1. The binding constant was 1.552 × 105 L∙mol−1, having a highly efficient and specific
  • irreversible nerve damage. Therefore, it is very important to develop a highly sensitive and selective method for mercury detection. At present, the detection of mercury mainly includes atomic absorption and atomic emission spectrometry [4], inductively coupled plasma mass spectrometry [5][6], and capillary
  • UV absorption intensity was achieved at n(Hg2+)/n((OST) + (Hg2+)) = 0.5 at 325 nm, indicating that the binding ratio of the OST probe to Hg2+ was 1:1. Combined with mass spectrometry data (Figure 5), the fragment peak of ESIMS at m/z 892.5422 corresponded to [OST2–Hg2]+ (calculated as 892.5429
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Published 05 Jan 2021

Molecular basis for protein–protein interactions

  • Brandon Charles Seychell and
  • Tobias Beck

Beilstein J. Org. Chem. 2021, 17, 1–10, doi:10.3762/bjoc.17.1

Graphical Abstract
  • proteins and other biological molecules, all of which have their own biological role and chemical interactions. Characterisation methods that can be employed to study PPIs can be divided into four categories: atomic resolution methods, mass spectrometry methods, biophysical methods, and computational
  • (or any other organic molecule [19]) structure. A resolution of up to 0.6 Å (RNA-binding protein FUS, residues 37–42, EMD-0699, PDB: 6KJ4 [20]) were obtained when using this method. Nannenga and Gonen gave a detailed account on MicroED [21]. As another category, mass spectrometry methods are used to
  • determine the amino acid sequences at the PPIs site. Examples include protein painting [22] and chemical cross-linking [23], hydrogen–deuterium exchange mass spectrometry (HDXMS) [24], and fast photochemical oxidation of proteins [25]. In protein painting, small-molecular dyes are introduced to protein
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Published 04 Jan 2021

Semiautomated glycoproteomics data analysis workflow for maximized glycopeptide identification and reliable quantification

  • Steffen Lippold,
  • Arnoud H. de Ru,
  • Jan Nouta,
  • Peter A. van Veelen,
  • Magnus Palmblad,
  • Manfred Wuhrer and
  • Noortje de Haan

Beilstein J. Org. Chem. 2020, 16, 3038–3051, doi:10.3762/bjoc.16.253

Graphical Abstract
  • complex, reflecting the high structural diversity of peptide and glycan portions. The use of glycopeptide-centered glycoproteomics by mass spectrometry is rapidly evolving in many research areas, leading to a demand in reliable data analysis tools. In recent years, several bioinformatic tools were
  • digest from affinity-purified immunoglobulins G and A was analyzed on a nano-reversed-phase liquid chromatography–tandem mass spectrometry platform with a high-resolution mass analyzer and higher-energy collisional dissociation fragmentation. Initial glycopeptide identification based on MS/MS data was
  • quantification. Keywords: bioinformatics; cysteine oxidation; glycoproteomics; immunoglobulins; mass spectrometry; Introduction Protein glycosylation mainly occurs in the form of N- and O-glycosylation. N-Glycans are attached to Asn within an amino acid consensus sequence (Asn-Xxx-Ser/Thr, Xxx ≠ Pro) and O
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Published 11 Dec 2020

Naphthalonitriles featuring efficient emission in solution and in the solid state

  • Sidharth Thulaseedharan Nair Sailaja,
  • Iván Maisuls,
  • Jutta Kösters,
  • Alexander Hepp,
  • Andreas Faust,
  • Jens Voskuhl and
  • Cristian A. Strassert

Beilstein J. Org. Chem. 2020, 16, 2960–2970, doi:10.3762/bjoc.16.246

Graphical Abstract
  • characterized by nuclear magnetic resonance spectroscopy (NMR, Supporting Information File 1, Figures S1–S24) as well as exact electrospray mass spectrometry (EM–ESIMS, Supporting Information File 1, Figures S25–S30) and appear as white to faint yellow solids. Only the dimethylamino-substituted product shows a
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Published 02 Dec 2020

Construction of pillar[4]arene[1]quinone–1,10-dibromodecane pseudorotaxanes in solution and in the solid state

  • Xinru Sheng,
  • Errui Li and
  • Feihe Huang

Beilstein J. Org. Chem. 2020, 16, 2954–2959, doi:10.3762/bjoc.16.245

Graphical Abstract
  • . Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI–TOF MS) was conducted to investigate the complexation properties. However, no signal related to the complex but only peaks of H were found, implying weak host–guest interactions between H and G (Figures S3 and S4
  • , Supporting Information File 1). A Job plot based on the proton NMR data was made to determine the complexation stoichiometry between H and G. The formation signified a 1:1 binding stoichiometry in chloroform-d at room temperature (Figures S5 and S6, Supporting Information File 1). Combined with the mass
  • spectrometry results, we believed that the differences between the stoichiometric ratio of the complexation in the solid state and in solution could be owing to the competitive role of solvent molecules in the combination of H and G. The association constant (Ka) calculated by the nonlinear curve fitting
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Published 02 Dec 2020

On the mass spectrometric fragmentations of the bacterial sesterterpenes sestermobaraenes A–C

  • Anwei Hou and
  • Jeroen S. Dickschat

Beilstein J. Org. Chem. 2020, 16, 2807–2819, doi:10.3762/bjoc.16.231

Graphical Abstract
  • enzymatic conversion of the correspondingly 13C-labelled isoprenyl diphosphate precursors with the sestermobaraene synthase from Streptomyces mobaraensis. The main compounds sestermobaraenes A, B, and C were analysed by gas chromatography–mass spectrometry (GC–MS), allowing for a deep mechanistic
  • investigation of the electron impact mass spectrometry (EIMS) fragmentation reactions of these sesterterpene hydrocarbons. Keywords: isotopes; mass spectrometry; reaction mechanisms; sesterterpenes; Streptomyces mobaraensis; Introduction The sestermobaraenes A–F (1–6) and sestermobaraol (7) are a series of
  • water, simple alcohols. These volatile compounds can efficiently be trapped by specialised methods including the closed-loop stripping apparatus (CLSA) [4] technique or solid-phase microextraction (SPME) [5][6], and then analysed by gas chromatography–mass spectrometry (GC–MS) [7]. Through these and
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Published 19 Nov 2020

Synthesis and investigation of quadruplex-DNA-binding, 9-O-substituted berberine derivatives

  • Jonas Becher,
  • Daria V. Berdnikova,
  • Heiko Ihmels and
  • Christopher Stremmel

Beilstein J. Org. Chem. 2020, 16, 2795–2806, doi:10.3762/bjoc.16.230

Graphical Abstract
  • moderate yields (16–38%), mainly because of severe difficulties to completely remove the copper ions that apparently bind tightly to the compounds. The new compounds 4a–e were identified and fully characterized with NMR spectroscopy (1H, 13C, COSY, HSQC, HMBC), mass spectrometry, and elemental analysis
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Published 18 Nov 2020

3-Acetoxy-fatty acid isoprenyl esters from androconia of the ithomiine butterfly Ithomia salapia

  • Florian Mann,
  • Daiane Szczerbowski,
  • Lisa de Silva,
  • Melanie McClure,
  • Marianne Elias and
  • Stefan Schulz

Beilstein J. Org. Chem. 2020, 16, 2776–2787, doi:10.3762/bjoc.16.228

Graphical Abstract
  • species in regions where they co-occur. Furthermore, the occurrence of positional isomers of unsaturated fatty acid derivatives indicates activity of two different desaturases within these butterflies, Δ9 and Δ11, which has not been reported before in male Lepidoptera. Keywords: fatty acid esters; mass
  • spectrometry; mimicry; pheromones; pyrrolizidine alkaloids; Introduction The Neotropical butterfly tribe Ithomiini (Nymphalidae: Danainae) is very diverse and species-rich, with over 390 species and 50 genera [1][2] and extensively involved in Müllerian mimetic interactions [3]. Ithomiines are well suited for
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Published 16 Nov 2020

Synthesis of purines and adenines containing the hexafluoroisopropyl group

  • Viacheslav Petrov,
  • Rebecca J. Dooley,
  • Alexander A. Marchione,
  • Elizabeth L. Diaz,
  • Brittany S. Clem and
  • William Marshall

Beilstein J. Org. Chem. 2020, 16, 2739–2748, doi:10.3762/bjoc.16.224

Graphical Abstract
  • mixture of 2a,b was washed with cold hexane on a ceramic filter to give a material with a 2a,b ratio of 95:5. Recrystallization of this sample from hexane gave the isomer 2b (purity 99%, by NMR), and this sample was used for an X-ray diffraction experiment. The reaction conditions, mass spectrometry, and
  • reaction conditions, mass spectrometry, and NMR data are given in Table 1 and Table 3. Reaction of 5-azabenzimidazole (4) and 1 A mixture of 1.2 g (0.01 mol) of 5-azabenzimidazole (4), 2 g (0.06 mol) of 1, and 15 mL of DMSO was agitated at ambient temperature for 24 h. The precipitated sulfur was filtered
  • acetate gradient, 100 mL/min, cartridge SNAP 340 g). The structure of each isomer was determined by X-ray diffraction. The reaction conditions, mass spectrometry, and NMR data are given in Table 1 and Table 3. Reaction of adenine (5) and 2-fluoroadenine (6), respectively, and 1 A mixture of 0.01 mol of
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Published 11 Nov 2020

Selective recognition of ATP by multivalent nano-assemblies of bisimidazolium amphiphiles through “turn-on” fluorescence response

  • Rakesh Biswas,
  • Surya Ghosh,
  • Shubhra Kanti Bhaumik and
  • Supratim Banerjee

Beilstein J. Org. Chem. 2020, 16, 2728–2738, doi:10.3762/bjoc.16.223

Graphical Abstract
  • obtained through nucleophilic substitution reactions between BImNs (N = 4, 10, 12, 14) and 3. All synthesized compounds were characterized by NMR spectroscopy and high-resolution mass spectrometry. Self-assembly properties of PBImNs in aqueous buffer The self-assembly properties of the four PBImN
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Published 10 Nov 2020

A heterobimetallic tetrahedron from a linear platinum(II)-bis(acetylide) metalloligand

  • Matthias Hardy,
  • Marianne Engeser and
  • Arne Lützen

Beilstein J. Org. Chem. 2020, 16, 2701–2708, doi:10.3762/bjoc.16.220

Graphical Abstract
  • diastereomers. The new complexes were characterized by NMR and UV–vis spectroscopy and ESI mass spectrometry. Using GFN2-xTB we generated energy-minimized models of the diastereomers of this cage that further corroborated the results from analytical findings. Keywords: cage compounds; heterobimetallic
  • , correlation of the proton. Low- and high-resolution electrospray ionization mass spectrometry (ESIMS) spectra were recorded on a Bruker Daltonic LTQ Orbitrap XL. The UV–vis spectrum was recorded on a Specord 200 spectrometer (Analytik Jena AG) at ambient temperature. 4-Ethynylaniline (1) [50], trans-[Pt(PBu3
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Published 03 Nov 2020

A consensus-based and readable extension of Linear Code for Reaction Rules (LiCoRR)

  • Benjamin P. Kellman,
  • Yujie Zhang,
  • Emma Logomasini,
  • Eric Meinhardt,
  • Karla P. Godinez-Macias,
  • Austin W. T. Chiang,
  • James T. Sorrentino,
  • Chenguang Liang,
  • Bokan Bao,
  • Yusen Zhou,
  • Sachiko Akase,
  • Isami Sogabe,
  • Thukaa Kouka,
  • Elizabeth A. Winzeler,
  • Iain B. H. Wilson,
  • Matthew P. Campbell,
  • Sriram Neelamegham,
  • Frederick J. Krambeck,
  • Kiyoko F. Aoki-Kinoshita and
  • Nathan E. Lewis

Beilstein J. Org. Chem. 2020, 16, 2645–2662, doi:10.3762/bjoc.16.215

Graphical Abstract
  • Rules Linear Code was first used to represent reaction rules in 2009. A reaction network, specifying glycans with condensed IUPAC and Linear Code, was trained on mass spectrometry abundance to learn biosynthetic enzyme activities [10]. Their reaction rules table contained four features: enzyme, reactant
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Commentary
Published 27 Oct 2020

Synthesis and characterization of S,N-heterotetracenes

  • Astrid Vogt,
  • Florian Henne,
  • Christoph Wetzel,
  • Elena Mena-Osteritz and
  • Peter Bäuerle

Beilstein J. Org. Chem. 2020, 16, 2636–2644, doi:10.3762/bjoc.16.214

Graphical Abstract
  • -heterotetracenes and -hexacene were clearly identified, fully characterized, and their structures confirmed by 1H and 13C NMR spectroscopy and high-resolution mass spectrometry (HRMS) via matrix-assisted laser desorption/ionization (MALDI) (Supporting Information File 1, Figures S1–S5). In the 1H NMR spectra, the
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Published 26 Oct 2020

Particle size effect in the mechanically assisted synthesis of β-cyclodextrin mesitylene sulfonate

  • Stéphane Menuel,
  • Sébastien Saitzek,
  • Eric Monflier and
  • Frédéric Hapiot

Beilstein J. Org. Chem. 2020, 16, 2598–2606, doi:10.3762/bjoc.16.211

Graphical Abstract
  • preparation of the investigated compound. Acknowledgements We thank N. Kania for BET analysis, J. Ternel for NMR experiments and J. Hachani for MALDI–TOF mass spectrometry. We are grateful to Dr. A. Fadel and Dr. A. Addad for their contribution in setting up the SEM measurements. Funding The SEM facility in
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Published 22 Oct 2020

Thermodynamic and electrochemical study of tailor-made crown ethers for redox-switchable (pseudo)rotaxanes

  • Henrik Hupatz,
  • Marius Gaedke,
  • Hendrik V. Schröder,
  • Julia Beerhues,
  • Arto Valkonen,
  • Fabian Klautzsch,
  • Sebastian Müller,
  • Felix Witte,
  • Kari Rissanen,
  • Biprajit Sarkar and
  • Christoph A. Schalley

Beilstein J. Org. Chem. 2020, 16, 2576–2588, doi:10.3762/bjoc.16.209

Graphical Abstract
  • supports the mechanically interlocked structure for NDIRot in analogy to similar structures investigated by tandem mass spectrometry earlier [35][40]. Cyclic voltammograms of NDIRot show two reversible reductions E1/2red1 and E1/2red2 independent of the used solvent (pure DCE or DCE/CH3CN 1:1, Figure S11
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Published 20 Oct 2020

Water-soluble host–guest complexes between fullerenes and a sugar-functionalized tribenzotriquinacene assembling to microspheres

  • Si-Yuan Liu,
  • Xin-Rui Wang,
  • Man-Ping Li,
  • Wen-Rong Xu and
  • Dietmar Kuck

Beilstein J. Org. Chem. 2020, 16, 2551–2561, doi:10.3762/bjoc.16.207

Graphical Abstract
  • fully characterized by 1H and 13C NMR spectroscopy and mass spectrometry (see Supporting Information File 1) and the data were found to be consistent with the proposed structures. For the hexakis-propargyl ether TBTQ-(OP)6, the signals at δ = 2.53 ppm in the 1H NMR spectrum and at δ = 78.98 and 76.07
  • detail by NMR spectroscopy and mass spectrometry. The host–guest complexation of TBTQ-(OG)6 with C60 and C70 takes place in a 1:1 molar ratio in both cases and with association constants of Ka = (1.50 ± 0.10) × 105 M−1 and Ka = (2.20 ± 0.16) × 105 M−1, respectively. It is suggested that the formation of
  • 474: 1H NMR, 13C NMR spectroscopy, and mass spectrometry of all new compounds, and the xyz coordinates (in Å) of the complex of TBTQ-(OG)6 with C60. Acknowledgements We acknowledge Prof. Xiang-Feng Chen for his help in the mass spectrometry testing. Funding The following sources of funding are
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Published 14 Oct 2020

Leveraging glycomics data in glycoprotein 3D structure validation with Privateer

  • Haroldas Bagdonas,
  • Daniel Ungar and
  • Jon Agirre

Beilstein J. Org. Chem. 2020, 16, 2523–2533, doi:10.3762/bjoc.16.204

Graphical Abstract
  • complexity of glycans in glycoproteins have been, and currently remain, significant challenges in structural biology. These aspects present unique problems to the two most prolific techniques: X-ray crystallography and cryo-electron microscopy. At the same time, advances in mass spectrometry have made it
  • alternative glycan composition exists in the form of, e.g., mass spectrometry data [14]. Harnessing glycomics and glycoproteomics results to inform glycan model building Current methods used to obtain accurate atomistic descriptions of molecules fall short in dealing with the heterogeneity of glycoproteins
  • . However, there are other methods that have been proven to successfully tackle the challenges posed by glycan heterogeneity, with mass spectrometry emerging as the one with the most relevance due to the ability to elucidate the complete composition descriptions of individual oligosaccharide chains on
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Published 09 Oct 2020

Computational tools for drawing, building and displaying carbohydrates: a visual guide

  • Kanhaya Lal,
  • Rafael Bermeo and
  • Serge Perez

Beilstein J. Org. Chem. 2020, 16, 2448–2468, doi:10.3762/bjoc.16.199

Graphical Abstract
  • this tool ideal for integrated use with various glycoinformatics software and also for applications in glycoproteomics, glycomics and mass spectrometry (MS). One of the illustrations involves combined use with the gpAnnotate application, dedicated to score and annotate MS/MS glycopeptide spectrums in
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Published 02 Oct 2020
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