Search results

Search for "mass spectrometry" in Full Text gives 612 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

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

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

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

Graphical Abstract
  • amount of Lawesson's reagent was increased to 3 equiv (Table 1, entry 5), the signal of thioketone was observed for the first time by high-performance liquid chromatography (HPLC) and MALDI time-of-flight mass spectrometry. Subsequently, a conversion of 99% was achieved by further increasing the amount
PDF
Album
Supp Info
Letter
Published 31 May 2024

Mechanistic investigations of polyaza[7]helicene in photoredox and energy transfer catalysis

  • Johannes Rocker,
  • Till J. B. Zähringer,
  • Matthias Schmitz,
  • Till Opatz and
  • Christoph Kerzig

Beilstein J. Org. Chem. 2024, 20, 1236–1245, doi:10.3762/bjoc.20.106

Graphical Abstract
  • , Supporting Information File 1) [76]. A reaction course plot in the absence of 4CP and TsNa revealed rapid decomposition of the photocatalyst, presumably in a [2 + 2]-photocycloaddition with the styrene component as observed in mass spectrometry (see Figure S17 and Figure S18 in Supporting Information File 1
  • reported similar efficiencies for the formation of both isomers starting from the perpendicular triplet state (Figure 5E) [35][83]. In contrast to styrene substrates, mass spectrometry shows no addition products of catalyst and stilbene. Hence, the photocatalyst is not consumed by side reactions
PDF
Album
Supp Info
Full Research Paper
Published 28 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
  • from through solvent (acetonitrile) oxidation was isolated as a colorless solid (vide infra). It was characterized by FTIR, 1H NMR, and mass spectrometry. The FTIR and mass spectrometry data were in accordance with the literature report [48][49]. Interestingly, the mass spectrum of the oxide 3 showed a
PDF
Album
Supp Info
Full Research Paper
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
  • the spontaneous formation of a limited quantity of 1 derived from 8, we detected the generation of products, including the previously characterized benzofluorene intermediate 4 and benzofluorene dimer 5, alongside a novel compound, designated as 10 (Figure 1, trace d). High-resolution mass
  • spectrometry (HRMS) analysis of 10 ([M − H]− calcd for C18H12O5, 307.0612; found, 307.0607, Figure S4, Supporting Information File 1) suggested a possible identity as hydroquinone–kinobscurinone [11]. However, attempts to elucidate the chemical structure of 10 were not successful due to the inherent
PDF
Album
Supp Info
Full Research Paper
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
  • perpendicularly. Unfortunately, the matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry of 3 afforded no molecular ion peak expected for adducts derived from Dip2Si and C60 while a base peak at m/z 720 due to C60 was observed probably because of the low stability of radical
PDF
Album
Supp Info
Full Research Paper
Published 22 May 2024
Graphical Abstract
  • spectroscopy. After 51 hours of reaction in boiling CH2Cl2, Diels–Alder adduct 27 was observed in 22% yield. Compound 27 was identified by 1H NMR and 13C NMR spectroscopies as well as high-resolution ESI mass spectrometry. Although the lack of reactivity observed for 3 and 23 limited our kinetic analysis, we
PDF
Album
Supp Info
Full Research Paper
Published 17 May 2024

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

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

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

Graphical Abstract
  • the enzymatic assays and the synthesis of nucleosides and modified ODNs, assignment of 1H, 13C, 31P NMR and IR spectra and results of HRESIMS experiments for new compounds synthesised as well as RP-HPLC profiles and HRESIMS spectra of ODNs. Acknowledgements NMR and mass spectrometry facilities at
PDF
Album
Supp Info
Full Research Paper
Published 15 May 2024

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
  • temperatures of 21 and 7 °C, respectively, from their corresponding DCPQ comparators. To complement the TGA studies, the thermal stability of compound 4b was evaluated through its exposure to air inside a 200 °C oven for one week. Structural evaluation by 2D NMR and mass spectrometry confirmed no decomposition
  • .: CHE-1057411; R.K.C./J.X.: CHE-1507561). K.A.A. wishes to acknowledge the NSF and the University of Florida for funding of the purchase of the X-ray equipment. The mass spectrometry data has been generated by the Mass Spectrometry Research and Education Center at the University of Florida which is
PDF
Album
Supp Info
Full Research Paper
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
  • supernatant. There are two main types of molecular probes based on their detection methods: imaging and UV–vis (Figure 2A). An imaging probe contains a mass spectrometry (MS) tag, oftentimes a halogen with a distinct isotopic ratio such as chlorine or bromine. A UV–vis probe contains a UV-tag, such as an
PDF
Album
Supp Info
Full Research Paper
Published 02 May 2024

Ortho-ester-substituted diaryliodonium salts enabled regioselective arylocyclization of naphthols toward 3,4-benzocoumarins

  • Ke Jiang,
  • Cheng Pan,
  • Limin Wang,
  • Hao-Yang Wang and
  • Jianwei Han

Beilstein J. Org. Chem. 2024, 20, 841–851, doi:10.3762/bjoc.20.76

Graphical Abstract
  • Technology, 130 Meilong Road, Shanghai 200237, P. R. China National Center for Organic Mass Spectrometry in Shanghai, Shanghai Institute of Organic Chemistry, The Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China 10.3762/bjoc.20.76 Abstract Cyclic annulation involving diaryliodonium
PDF
Album
Supp Info
Letter
Published 18 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
  • carborane A3B-porphyrin were also synthesized based on the amino-substituted A3B-porphyrin. The structures of the prepared carboranylporphyrins were determined by UV–vis, IR, 1H, 19F, 11B NMR spectroscopic data and MALDI mass spectrometry. Keywords: bioconjugation; carboranes; fluorine; porphyrin; SNAr
  • azide substituent in porphyrin 2 with SnCl2·2H2O in MeOH resulted in the formation of porphyrin amino-derivative 3 in 82% yield (Scheme 1). The molecular structures of compounds 2 and 3 were confirmed by a combination of NMR spectroscopy and mass spectrometry. Having synthesized porphyrins 2 and 3 we
  • easily converted into hydrophilic charged entities by the protonation of the unsubstituted amino functionalities in their structure providing improved bioconjugation. Spectroscopic data All porphyrin conjugates were structurally characterized by IR, UV–vis, NMR spectroscopy, and mass spectrometry. The IR
PDF
Album
Supp Info
Full Research Paper
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
  • is still important. Previous approaches to determine KS domain specificities have involved mass spectrometry (MS)-based methods [22][23], MS analysis of trypsin-digested proteins [24], and radiochemical assays [25]. Here, we report on a new method using 13C-labelled substrate surrogates in
PDF
Album
Supp Info
Letter
Published 05 Apr 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
  • four enzymes in the Aspergillus oryzae NSARU1 strain [19]. Consequently, the A. oryzae transformant yielded two metabolites 1 and 2, which were absent in the host strain (Figure 2B, traces i and ii). Although we were unable to isolate compounds 1 and 2 because of their instability, high-resolution mass
  • spectrometry (HRMS) analysis revealed the molecular formula of 1 to be C25H36O5, corresponding to the 4-desmethyl form of (6R,10′R)-epoxyfarnesyl-DMOA methyl ester (Figure 2C). Furthermore, the molecular formula of 2 was determined to be C25H38O6, indicating that 2 is formed by the hydrolysis of the epoxide
PDF
Album
Supp Info
Letter
Published 20 Mar 2024

Introduction of a human- and keyboard-friendly N-glycan nomenclature

  • Friedrich Altmann,
  • Johannes Helm,
  • Martin Pabst and
  • Johannes Stadlmann

Beilstein J. Org. Chem. 2024, 20, 607–620, doi:10.3762/bjoc.20.53

Graphical Abstract
  • the time being. Comparison with existing abbreviation systems Finally, we shall compare the herein portrayed naming system with existing ones. There are several systems of which a few occur more often. The most stringent and rigorous way to annotated mass spectrometry data is to give the sum formula
PDF
Album
Supp Info
Perspective
Published 15 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
  • pursuit are equally significant. One of the efficient approaches for finding new secondary metabolites from microorganisms is physicochemical (PC) screening. This approach involves the screening of the physicochemical properties of potential compounds, such as UV spectroscopy, mass spectrometry, and color
  • was concentrated in vacuo to yield 1 (7.9 mg). LC–MS analysis Electrospray ionization-mass spectrometry (ESIMS) data was collected using a Triple TOF 5600+ LC–MS/MS System (AB Sciex, Framingham, MA, USA) with an ODS column (Capcell Core C18, 3.0 i.d. × 100 mm, 40 °C) (Osaka Soda, Japan) at a flow rate
PDF
Album
Supp Info
Full Research Paper
Published 29 Feb 2024

Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters

  • Carlos R. Azpilcueta-Nicolas and
  • Jean-Philip Lumb

Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35

Graphical Abstract
  • substitution with alcohol 94 in the presence of lithium phthalimide 95 leads to product 96 and turns over the catalytic cycle. Importantly, species 93 can be detected by high resolution mass spectrometry, when the reaction is carried out without nucleophile and using stoichiometric amounts of PTH1. H. Fu and
PDF
Album
Perspective
Published 21 Feb 2024

Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

  • Eugeny Ivakhnenko,
  • Vasily Malay,
  • Pavel Knyazev,
  • Nikita Merezhko,
  • Nadezhda Makarova,
  • Oleg Demidov,
  • Gennady Borodkin,
  • Andrey Starikov and
  • Vladimir Minkin

Beilstein J. Org. Chem. 2024, 20, 336–345, doi:10.3762/bjoc.20.34

Graphical Abstract
  • 15N NMR spectroscopy (NMR spectra of compounds 4a–h, 5a–c, 6a,b, and 10c are given in Figures S13–S43, Supporting Information File 1), mass spectrometry (Figures S44–S56, Supporting Information File 1), IR and UV–vis spectroscopy, as well as elemental analysis. The NMR spectra were recorded on the
PDF
Album
Supp Info
Full Research Paper
Published 21 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
  • min−1). High-resolution mass spectra were recorded on an ABSciex TripleTOF 6600+ mass spectrometer. Direct infusion of compounds 1 and 2 through the high-resolution mass spectrometry (HRMS) was performed using a flow rate of 10 μL min−1 which the samples were diluted at 10 ppm with a solution of MeCN
PDF
Album
Supp Info
Full Research Paper
Published 19 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
  • treated with 90% aq trifluoroacetic acid in CH2Cl2 to give diol 7 (70% yield) that was formed due to migration of a chloroacetyl group from O-7 to O-9. The structure of diol 7 was established by NMR spectroscopy, high-resolution mass spectrometry and X-ray diffraction analysis (see the Experimental
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
  • treated with 1 M Bu4NF/THF and after 2 hours, full consumption of the starting material was observed by TLC. However, MALDI–TOF mass spectrometry (super-DHB matrix) revealed that only the Troc group had been removed, with the DTBS substituent proving to be stable under these conditions. Addition of a
  • reported to one decimal point unless an additional digit was required to distinguish overlapping peaks. Software for data processing: MestReNova, version 11.0.0–17609 (MestReLab Research S.L.). High-resolution mass spectrometry (HRMS) data were recorded on a Waters Micromass LCT LC–TOF instrument using
  • electrospray ionisation (ESI) in positive mode. MALDI–TOF mass spectrometry data were recorded on a Scientific Analysis Instruments MALDI–TOF mass spectrometer in reflectron mode for oligosaccharides and in linear mode for glycoconjugates. Samples were prepared by pre-mixing 1 µL of a solution containing the
PDF
Album
Supp Info
Full Research Paper
Published 30 Jan 2024

Visible-light-induced radical cascade cyclization: a catalyst-free synthetic approach to trifluoromethylated heterocycles

  • Chuan Yang,
  • Wei Shi,
  • Jian Tian,
  • Lin Guo,
  • Yating Zhao and
  • Wujiong Xia

Beilstein J. Org. Chem. 2024, 20, 118–124, doi:10.3762/bjoc.20.12

Graphical Abstract
  • NMR (Figure S3 in Supporting Information File 1) [30] and high-resolution mass spectrometry. You and co-workers proposed a reaction pathway involving the combination of the indole substrate and Umemoto’s reagent to form an electron donor–acceptor (EDA) complex [31]. We excluded the possibility of an
PDF
Album
Supp Info
Full Research Paper
Published 19 Jan 2024

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

  • Julika Schlosser,
  • Olga Fedorova,
  • Yuri Fedorov and
  • Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

Graphical Abstract
  • the amine 2b gave the corresponding amide 2g in 28% yield. The chloro-substituted derivative 2e was synthesized in a Sandmeyer-reaction from 2b in 20% yield. The products 2a–g were identified and fully characterized by NMR spectroscopy (1H, 13C, COSY, HSQC, and HMBC), elemental analyses, and mass
  • spectrometry. In all cases, the E-configuration of the alkene double bonds was indicated by characteristic coupling constants of the alkene protons (3JH–H = 16 Hz). Absorption properties and photoreactions of styrylpyridine derivatives In acetonitrile solution, the styrylpyridines 2a–g exhibited long
PDF
Album
Supp Info
Full Research Paper
Published 18 Jan 2024

Cycloaddition reactions of heterocyclic azides with 2-cyanoacetamidines as a new route to C,N-diheteroarylcarbamidines

  • Pavel S. Silaichev,
  • Tetyana V. Beryozkina,
  • Vsevolod V. Melekhin,
  • Valeriy O. Filimonov,
  • Andrey N. Maslivets,
  • Vladimir G. Ilkin,
  • Wim Dehaen and
  • Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2024, 20, 17–24, doi:10.3762/bjoc.20.3

Graphical Abstract
  • effect on the yield of the final compounds 3 observed. The structures of compounds 3a–u were confirmed by IR, 1H and 13C NMR spectroscopy (Figures S1‒S44 in Supporting Information File 1) as well as by high-resolution mass spectrometry (HRMS). X-ray data obtained for compound 3g gave us final proof of
PDF
Album
Supp Info
Full Research Paper
Published 05 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
  • regulator (cmaR), under the control of tipA promoter (Figure 2A). When we cultured S. albus-cma and analyzed its metabolites by liquid chromatography–mass spectrometry (LC–MS), formation of avenalumic acid was not observed. Instead, production of p-coumaric acid (5) was detected (Figure 2B and Figure S3A,D
  • and evaporated completely in vacuo. The residual materials were dissolved in 200 µL of methanol. The obtained samples were analyzed by liquid chromatography–electrospray ionization mass spectrometry (LC–ESIMS) using an LC-2040C 3D Plus system (Shimazu Corp., Kyoto, Japan) equipped with a COSMOCORE
PDF
Album
Supp Info
Full Research Paper
Published 02 Jan 2024

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

  • Nedra Touj,
  • François Mazars,
  • Guillermo Zaragoza and
  • Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

Graphical Abstract
  • carbenes with a strong base, followed by their nucleophilic addition onto carbon disulfide. The nine products obtained were characterized by 1H and 13C NMR spectroscopy, FTIR spectroscopy, HR–ESI mass spectrometry, and elemental analysis. Moreover, the molecular structures of two CAAC·CS2 and two MIC·CS2
PDF
Album
Supp Info
Full Research Paper
Published 20 Dec 2023
Other Beilstein-Institut Open Science Activities