Polymer degrading marine Microbulbifer bacteria: an un(der)utilized source of chemical and biocatalytic novelty

• Weimao Zhong and
• Vinayak Agarwal

Beilstein J. Org. Chem. 2024, 20, 1635–1651, doi:10.3762/bjoc.20.146

• known parabens (2, 5, 6, and 11), five new ones (7–10, and 12) were identified. Their structures were elucidated by high-resolution mass spectrometry (HRMS) and 1D and 2D nuclear magnetic resonance (NMR). The configuration in 8 and 10 remained undetermined. Antimicrobial activities of compounds 2 and 5

• Microbulbifer bacteria and is not limited to Microbulbifer strains isolated from either coral or sponge microbiomes. Imaging mass spectrometry demonstrated that bulbiferamides are excreted by Microbulbifer bacterial colonies into the extracellular media. Based on the characteristic mass spectrometric

Hypervalent iodine-catalyzed amide and alkene coupling enabled by lithium salt activation

• Akanksha Chhikara,
• Fan Wu,
• Navdeep Kaur,
• Prabagar Baskaran,
• Alex M. Nguyen,
• Zhichang Yin,
• Anthony H. Pham and
• Wei Li

Beilstein J. Org. Chem. 2024, 20, 1405–1411, doi:10.3762/bjoc.20.122

• . Acknowledgements We thank Dr. Yong W. Kim (University of Toledo) for NMR assistance. Mr. Babatunde Obadawo (University of Toledo) is acknowledged for collecting the high-resolution mass spectrometry data. We acknowledge Dr. Navdeep Kaur’s Ph. D. for her contributions in her Ph. D. thesis titled “Selective

Synthesis of 1,2,3-triazoles containing an allomaltol moiety from substituted pyrano[2,3-d]isoxazolones via base-promoted Boulton–Katritzky rearrangement

• Constantine V. Milyutin,
• Andrey N. Komogortsev and
• Boris V. Lichitsky

Beilstein J. Org. Chem. 2024, 20, 1334–1340, doi:10.3762/bjoc.20.117

• spectroscopy and high-resolution mass spectrometry. Moreover, X-ray analysis was used for confirmation of structure of compound 4g (Figure 1). A plausible mechanism of the studied rearrangement is presented in Scheme 5. At first, anion A is generated from starting hydrazone 3 under action of base. Next

• obtained the recyclized product 6a (Scheme 6), whose structure was confirmed by 1H, 13C NMR spectroscopy, high-resolution mass spectrometry and X-ray analysis. Based on the aforementioned reaction we have synthesized a set of pyrazolylisoxazoles 6 (Scheme 7). The proposed mechanism of investigated

Computation-guided scaffold exploration of 2E,6E-1,10-trans/cis-eunicellanes

• Zining Li,
• Sana Jindani,
• Volga Kojasoy,
• Teresa Ortega,
• Erin M. Marshall,
• Khalil A. Abboud,
• Sandra Loesgen,
• Dean J. Tantillo and
• Jeffrey D. Rudolf

Beilstein J. Org. Chem. 2024, 20, 1320–1326, doi:10.3762/bjoc.20.115

• crystallographic information. Acknowledgements We acknowledge the University of Florida Center for Nuclear Magnetic Resonance Spectroscopy and Ion Ghiviriga for excellent NMR support. We acknowledge the University of Florida Mass Spectrometry Research and Education Center (MSREC), which is supported by the NIH

Diameter-selective extraction of single-walled carbon nanotubes by interlocking with Cu-tethered square nanobrackets

• Guoqing Cheng and
• Naoki Komatsu

Beilstein J. Org. Chem. 2024, 20, 1298–1307, doi:10.3762/bjoc.20.113

• extraction, the square Cu-nanobrackets 1b were successfully obtained by the reaction between the nanobracket 4b and copper(II) acetylacetonate in THF at room temperature. The product was characterized as 1b by MALDI-TOF mass spectrometry (Figure 1a), absorption (Figure 1b) and Raman (Figure 2c

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

• 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

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

• , 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

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

• 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

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

• 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

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

• 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

Kinetically stabilized 1,3-diarylisobenzofurans and the possibility of preparing large, persistent isoacenofurans with unusually small HOMO–LUMO gaps

• Qian Liu and
• Glen P. Miller

Beilstein J. Org. Chem. 2024, 20, 1099–1110, doi:10.3762/bjoc.20.97

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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

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

• 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