A cascade synthesis of 2-aminothiochromones from 2-fluorophenyl ketone and thiocarbonyldiimidazole

• Kai Zhang,
• Haofan Shao,
• Kangjun Liao,
• Ying Xu,
• Shimei Du,
• Yanfang Zhao,
• Gang Li,
• Wenzhen Xu,
• Haihong Huang and
• Peng Li

Beilstein J. Org. Chem. 2026, 22, 1151–1159, doi:10.3762/bjoc.22.92

• thiocarbonyl group of TCDI (1a’’) with displacing one molecule of imidazole forms intermediate A, which was detected by mass spectrometry. However, intermediate A is unstable and rapidly cyclizes during work-up or purification. This process proceeds via a second deprotonation to generate a thiolate anion (A

• intermediate B, leading to the expulsion of the second imidazole molecule (B’). Notably, the key intermediate B was isolated from the reaction mixture, while intermediate A was characterized by mass spectrometry during the reaction. Collectively, these results indicate that the initial generation of a

• characterizations of the prepared compounds were performed by 1H NMR and 13C NMR spectroscopy and high-resolution mass spectrometry (HRMS). 1H NMR spectra were obtained on an ECZ-400 spectrometer (JEOL, Tokyo, Japan) at 400 MHz and a Bruker AVANCE 500 (Bruker, Rheinstetten, Germany) at 500 MHz. 13C NMR spectra were

Discovery of sugarnitriles A and B, and structural reassignment of SF-2140, from a sugarcane endophytic actinomycete Amycolatopsis sp. JS-O27

• Qiuyun Li,
• Ying Liu,
• Baoyue Wei,
• Yu Sun,
• Di Mao,
• Yanmin Zou and
• Shan Lu

Beilstein J. Org. Chem. 2026, 22, 1114–1121, doi:10.3762/bjoc.22.90

• Avance III HD 400 NMR spectrometer. Mass and high-resolution mass spectrometry (HRMS) spectra were obtained on an Agilent 1260-6120 LC/MS spectrometer or a Waters Xevo G2-XS QT mass spectrometer. CD spectra were recorded at 25 °C on a JASCO J-815 CD spectropolarimeter with a 0.2 cm path length cell

Controlled supramolecular assemblies of luminescent tridentate cyclometalated alkynylgold(III) amphiphiles in aqueous media

• Kelvin Sze-Yim Cai,
• Brian Boyan Liu and
• Franco King-Chi Leung

Beilstein J. Org. Chem. 2026, 22, 1097–1106, doi:10.3762/bjoc.22.88

• all newly synthesized compounds and GA were unambiguously characterized by 1H , 13C NMR spectroscopy and high-resolution mass spectrometry (HRMS) (Supporting Information File 1, Figures S8–S13). Photophysical properties and assembly of GA A freshly prepared aqueous solution of GA (13.4 mM, 1.0 wt

Synthesis of functionalized, 13-alkyl-substituted coralyne derivatives and investigation of their interactions with duplex and abasic site-containing DNA

• Laurin Beckmann,
• Jason Lennard Kunze,
• Hannah Karola Strunk,
• Maurice Michel and
• Heiko Ihmels

Beilstein J. Org. Chem. 2026, 22, 1057–1066, doi:10.3762/bjoc.22.84

• the hydroxyalkyl-substituted product 3f in 45% yield (over the two reaction steps). All novel compounds were identified and characterized by 1H and 13C NMR spectroscopy (2D, COSY, HSQC, HMBC), mass spectrometry, and elemental analysis (if necessary as hydrochloride salts). Additionally, IR

• ). Under these conditions, the azide 3e decomposed, as indicated by 1H NMR-spectroscopic analysis of the reaction mixture, whereas the bromoalkyl-substituted papaverine 3b gave the coralyne derivative 2b, albeit in a very low yield of 1%. The product 2b was identified by NMR spectroscopy, mass spectrometry

• hydrolysis to give the coralyne carboxylic acid derivative 2d in 93% yield (Scheme 3). The novel compounds 2c and 2d were identified and characterized by NMR spectroscopy (1H, 13C, COSY, HSQC, HMBC), mass spectrometry, and elemental analysis. For the synthesis of a reference compound without alkoxyamine unit

Synthesis of novel 1,2,4-oxadiazole-isoxazoline hybrids and their in silico potential with adenosine receptors

• Pshtiwan S. Mohammed,
• Mohammed K. S. Dalo,
• Onur C. Yazıcı,
• Muhammet Yildirim and
• Akın Sağırlı

Beilstein J. Org. Chem. 2026, 22, 1033–1047, doi:10.3762/bjoc.22.82

• contribute to the observed low yields. The structures of all synthesized products 7a–ay were fully determined using IR, NMR, mass spectrometry, and relevant physical data. In the IR spectra of compounds 7a–ay, characteristic absorption bands were observed at approximately 3050, 2900, 1600, 1250, and 830 cm−1

• regioselectivity of the applied nitrile oxide cycloaddition reactions (Scheme 4). Moreover, the molecular masses of all compounds 7a–ay were unambiguously confirmed by high-resolution mass spectrometry, which showed the expected M+ or [M + H]+ ions. (See Experimental section for physical, spectroscopic data and

The role of spacer length and flexibility in peptide self-assembly

• Julian Link,
• Albin Lahu,
• Manfred Wagner,
• Tanja Weil and
• David Y. W. Ng

Beilstein J. Org. Chem. 2026, 22, 986–996, doi:10.3762/bjoc.22.77

• of spectra. Acknowledgements The authors acknowledge the members of the MS core facility for the support with mass spectrometry measurements in this project. Furthermore, the authors thank Helma Burg (Scanning Probe Core Facility of the MPIP) for supporting our work with topography measurements. The

• (C0-Nap, 5) was obtained from compound 2 and ʟ-isoleucine. The products were washed with 1 M HCl and brine and did not require further purification. The naphthalene imides 3, 4, and 5 were obtained with good yields (87–99%) and in high purities (90–95%) as characterized by liquid chromatography–mass

• spectrometry (LC–MS) and NMR spectroscopy (Supporting Information File 1, Figures S7–S24). The target tripeptide (ICA) was synthesized in a microwave-assisted peptide synthesizer using the fluorenylmethyloxycarbonyl (Fmoc) solid-phase peptide synthesis strategy [37], synthesizing the peptide from the C- to N

Synthesis of heterocycles based on azomethine ylides from α-amino acids (or amines) and carbonyl compounds

• Ekaterina V. Berezhnaya,
• Alexander I. Ponyaev,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2026, 22, 705–741, doi:10.3762/bjoc.22.55

• electron-deficient central multiple bond of triarylidene acetylacetone. The cleavage of the cinnamoyl group that occurs during the formation of spiroheterocycles was additionally confirmed using mass spectrometry [103]. In [104][105], our group investigated three-component one-pot reactions of substituted

Melifoliox B, a novel phloroglucin derivative isolated from Melicope barbigera (Rutaceae) and synthesis of new oxidation products from melifoliones A and B

• Horst Weber,
• Kim-Thao Tran-Cong,
• Bernhard Mayer,
• Guido J. Reiss,
• Iryna S. Konovalova,
• Marc S. Appelhans,
• Kenneth R. Wood and
• Claus M. Passreiter

Beilstein J. Org. Chem. 2026, 22, 535–546, doi:10.3762/bjoc.22.39

• resolution electrospray ionization mass spectrometry (HRESIMS) and NMR spectra. However, the isomeric compound 3 could not be detected in the extract (Figure 1). Since 4 could be an artefact, built by oxidation of 2 during working up of the extract, and to finally confirm the structure, the isomeric

• colorless and amorphous substance. The molecular formula was determined as C18H22O5 by high resolution electrospray ionization mass spectrometry (HRESIMS), thus containing one more oxygen atom than the melifoliones. The UV spectrum showed a maximum at 250 nm, typical for an α,β-unsaturated carbonyl

Get a better glimpse on sequential photoreactions of trisnorbornadienes with ¹⁹F NMR spectroscopy

• Julian Felix Maria Hebborn,
• Ben Eric Merten,
• Thomas Paululat and
• Heiko Ihmels

Beilstein J. Org. Chem. 2026, 22, 527–534, doi:10.3762/bjoc.22.38

• trisnorbornadiene 1f was synthesized in 36% yield through a Suzuki–Miyaura coupling reaction of tribromotrifluorobenzene 3 with the 2-borononorbornadiene 1e (Scheme 2) [43]. The product 1f was identified and fully characterized by NMR spectroscopy (1H, 13C, 19F, COSY, HSQC, HMBC), mass spectrometry, melting point

Synthesis of a HDAC inhibitor–nanogold probe for cryo-EM visualization in class I HDAC co-repressor complexes

• Wiktoria A. Pytel,
• John W. R. Schwabe and
• James T. Hodgkinson

Beilstein J. Org. Chem. 2026, 22, 480–485, doi:10.3762/bjoc.22.35

• for assistance and guidance in Cryo-EM experiments. We thank Dr. Vanessa M. Timmermann and Dr. Rebecca Hawker for assistance in NMR analysis and Dr. Sharad C. Mistry for assistance in mass spectrometry. Funding We thank the following funders: EPSRC (EP/S030492/1 to JTH; EP/W02151X/1 NMR facility); MRC

Synthesis and anti-cancer activity of naphthalimide–organylselanyl conjugates

• Rajkumar Ravi and
• Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2026, 22, 416–435, doi:10.3762/bjoc.22.29

• conserved 3-(4-(tert-butyl)phenoxy)propyl function at the imide nitrogen. The resultant naphthalimide–organylselanyl conjugates, NAP-SePh and NAP-Se(n-Oct), were characterised using various spectroscopic techniques, including FTIR, ¹H, ¹³C, ⁷⁷Se NMR and high-resolution mass spectrometry (HRMS). NAP-SePh was

• single-crystal X-ray diffraction data. To perform high-resolution electrospray ionisation mass spectrometry (HRESIMS), a Waters Xevo G2-XS QT spectrometer was used. Fourier transform infrared (FTIR) spectra were recorded on an Agilent Cary 630 spectrometer using a KBr module. Naphthalimide derivatives 10

Design, synthesis and biological evaluation of 2,5-diaryloxazolo[4,5-d]pyrimidin-7-ylamines as selective cytotoxic agents against HeLa cells

• Maryna V. Kachaeva,
• Agnieszka B. Olejniczak,
• Marta Denel-Bobrowska,
• Victor V. Zhirnov,
• Yevheniia S. Velihina,
• Stepan G. Pilyo and
• Volodymyr S. Brovarets

Beilstein J. Org. Chem. 2026, 22, 390–398, doi:10.3762/bjoc.22.27

• liquid chromatography–mass spectrometry. Their anticancer activity was assessed against human cancer cell as well as non-cancer cell lines. Three compounds, 1, 3, and 9, were the most cytotoxic to HeLa cells (IC50 = 6.13 ± 1.95, 13.99 ± 1.80 and 49.92 ± 3.98 μM, respectively). However, only compounds 1

Synthesis of diaryl phosphates using phytic acid as a phosphorus source

• Kazuya Asao,
• Seika Matsumoto,
• Haruka Mori,
• Riku Yoshimura,
• Takeshi Sasaki,
• Naoya Hirata,
• Yasuyuki Hayakawa and
• Shin-ichi Kawaguchi

Beilstein J. Org. Chem. 2026, 22, 213–223, doi:10.3762/bjoc.22.15

• File 1. The isolated compounds were characterized via NMR (1H, 13C, 19F, and 31P) and low-resolution mass spectrometry measurements. The NMR measurements were conducted using a Varian NMR 400 MHz system (400 MHz) and a Bruker AVANCE NEO console (400 MHz). Mass spectrometry was performed using LCMS-2020

• Supporting Information File 24: Experimental section, characterization data and copies of spectra. Acknowledgements We acknowledge the Analytical Research Center for Experimental Science, Saga University, for the NMR spectroscopy and mass spectrometry measurements. We thank Editage (https://www.editage.com

Design and synthesis of an axially chiral platinum(II) complex and its CPL properties in PMMA matrix

• Daiki Tauchi,
• Sota Ogura,
• Misa Sakura,
• Kazunori Tsubaki and
• Masashi Hasegawa

Beilstein J. Org. Chem. 2026, 22, 143–150, doi:10.3762/bjoc.22.7

• spectroscopy, as well as high-resolution mass spectrometry (HRMS). Due to its low solubility, single crystals suitable for X-ray crystallographic analysis could not be obtained. Spectroscopic analysis and DFT calculations To elucidate the electronic structure of the platinum(II) complex, UV–vis absorption

Symmetrical D–π–A–π–D indanone dyes: a new design for nonlinear optics and cyanide detection

• Ergin Keleş,
• Alberto Barsella,
• Nurgül Seferoğlu,
• Zeynel Seferoğlu and
• Burcu Aydıner

Beilstein J. Org. Chem. 2026, 22, 131–142, doi:10.3762/bjoc.22.6

• , 13C NMR, and mass spectrometry methods. Dye structures were designed with alkylaminophenyl groups, known for their various electron-donating properties, as donors, and the dicyanovinyl group, with its strong electron-withdrawing properties, as acceptors, conjugated with an indan-2-one core (Figure 1

• method (CM)) (Scheme 1, Table 1). All syntheses were also carried out with microwave irradiation (MWI), which had a short reaction time; however, no improvement in yield was achieved (see Supporting Information File 1). The structural analyses of the compounds were performed using 1H/13C NMR and mass

• spectrometry methods (Figures S1–S10 in Supporting Information File 1). Optical properties of dyes Photophysical properties of dyes 2a–c were assessed in four different organic solvents with various polarities (DMSO, acetone, chloroform, and THF) via absorption spectra and DFT calculations (Table 2). Figure 2a

Highly electrophilic, gem- and spiro-activated trichloromethylnitrocyclopropanes: synthesis and structure

• Ilia A. Pilipenko,
• Mikhail V. Grigoriev,
• Olga Yu. Ozerova,
• Igor A. Litvinov,
• Darya V. Spiridonova,
• Aleksander V. Vasilyev and
• Sergey V. Makarenko

Beilstein J. Org. Chem. 2026, 22, 123–130, doi:10.3762/bjoc.22.5

• conditions. The reaction is carried out either in tetrahydrofuran in the presence of triethylamine or in methanol in the presence of fused potassium acetate. The structures of the isolated individual products were characterized by 1H and 13C NMR, IR spectroscopy, mass spectrometry, and confirmed by single

Reactivity umpolung of the cycloheptatriene core in hexa(methoxycarbonyl)cycloheptatriene

• Dmitry N. Platonov,
• Alexander Yu. Belyy,
• Rinat F. Salikov,
• Kirill S. Erokhin and
• Yury V. Tomilov

Beilstein J. Org. Chem. 2026, 22, 64–70, doi:10.3762/bjoc.22.2

• negative free energy changes for all the stages of this reaction. A chlorination experiment with 2,2,6,6-tetramethylpiperidinyloxyl revealed a trace amount of a trap product detected by high-resolution mass spectrometry to support the radical mechanism. However, this does not exclude the possibility of a

Thiazolidinones: novel insights from microwave synthesis, computational studies, and potentially bioactive hybrids

• Luan A. Martinho,
• Victor H. J. G. Praciano,
• Guilherme D. R. Matos,
• Claudia C. Gatto and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2025, 21, 2618–2636, doi:10.3762/bjoc.21.203

• inconsistency made it challenging to rely on NMR as the primary method for confirming the structure of the expected products. To overcome this limitation, other analytical techniques, such as mass spectrometry and infrared (IR) spectroscopy, were employed. These methods successfully corroborated the formation

Efficient solid-phase synthesis and structural characterization of segetalins A–H, J and K

• Liangyu Liu,
• Wanqiu Lu,
• Quanping Guo and
• Zhaoqing Xu

Beilstein J. Org. Chem. 2025, 21, 2612–2617, doi:10.3762/bjoc.21.202

• electrospray ionization mass spectrometry (HRESIMS) data for all compounds matched the calculated exact masses for their respective molecular formulas. NMR spectroscopic analysis in appropriate deuterated solvents (e.g., DMSO-d6, D2O) fully corroborated the amino acid sequence and cyclic connectivity

Effect of a photoswitchable rotaxane on membrane permeabilization across lipid compositions

• Udyogi N. K. Conthagamage,
• Lilia Lopez,
• Zuliah A. Abdulsalam and
• Víctor García-López

Beilstein J. Org. Chem. 2025, 21, 2498–2512, doi:10.3762/bjoc.21.192

• -deuterated solvent signals (acetonitrile-d3: δH = 1.94 ppm, δC = 1.32 ppm). Coupling constant (J) values are in hertz (Hz). Resonance multiplicities are described as s (singlet), app s (apparent singlet), d (doublet), t (triplet), q (quartet), m (multiplet), and br (br). Mass spectrometry (MS) was conducted

• at the Louisiana State University Mass Spectrometry Facility using the Waters Synapt XS ESI Q-TOF instrument. The main peaks and clusters are reported in m/z units, with M+ representing the molecular ion and the corresponding intensities in percent. UV–vis studies were carried out using an Agilent

Conformational effects on iodide binding: a comparative study of flexible and rigid carbazole macrocyclic analogs

• Guang-Wei Zhang,
• Yong Zhang,
• Le Shi,
• Chuang Gao,
• Hong-Yu Li and
• Lei Xue

Beilstein J. Org. Chem. 2025, 21, 2369–2375, doi:10.3762/bjoc.21.181

• . Experimental PBG (CCDC Number: 2070280) and WDG were synthesized from phenyl- and fluorenyl-substituted precursors, respectively, via Friedel–Crafts alkylation (Scheme 1) according to our previous work [22]. Structural characterization was performed using 1H NMR (Figures S1 and S2) and mass spectrometry

Insoluble methylene-bridged glycoluril dimers as sequestrants for dyes

• Suvenika Perera,
• Peter Y. Zavalij and
• Lyle Isaacs

Beilstein J. Org. Chem. 2025, 21, 2302–2314, doi:10.3762/bjoc.21.176

• -insoluble acyclic CB[n]-type receptors that possess benzene (G2W4), naphthalene (G2W3), and triphenylene (G2W1 and G2W2) walls bearing methoxy substituents. The new hosts were fully characterized by 1H NMR, 13C NMR, IR, mass spectrometry, and X-ray crystallography (G2W1 and G2W3). We studied the efficiency

• are reported in cm−1. Mass spectrometry was performed using a JEOL AccuTOF electrospray instrument (ESI). The dye uptake was quantified by UV–vis spectroscopy (Cary 100 Bio UV–visible spectrophotometer) at 25 °C. Incubation of hosts with dyes was performed using an Eppendorf ThermoMixer™ C in 1.5 mL

A chiral LC–MS strategy for stereochemical assignment of natural products sharing a 3-methylpent-4-en-2-ol moiety in their terminal structures

• Rei Suo,
• Raku Irie,
• Hinako Nakayama,
• Yuta Ishimaru,
• Yuya Akama,
• Masato Oikawa and
• Shiro Itoi

Beilstein J. Org. Chem. 2025, 21, 2243–2249, doi:10.3762/bjoc.21.171

• research areas, including the development of synthetic methodologies, the investigation of modes of action, and the evaluation of pharmacological potential, among others. Advancements in spectroscopic techniques, such as nuclear magnetic resonance (NMR) and mass spectrometry (MS), have enabled the

• absolute configuration of scarce natural products, including heptavalinamide A [11] and poecillastrin C [12][13] by a combination of chemical degradation, chemical synthesis, and liquid chromatography–mass spectrometry (LC–MS) analysis. The 3-methylpent-4-en-2-ol (MPO) moiety is commonly found at the

Thiadiazino-indole, thiadiazino-carbazole and benzothiadiazino-carbazole dioxides: synthesis, physicochemical and early ADME characterization of representatives of new tri-, tetra- and pentacyclic ring systems and their intermediates

• Gyöngyvér Pusztai,
• László Poszávácz,
• Anna Vincze,
• András Marton,
• Ahmed Qasim Abdulhussein,
• Judit Halász,
• András Dancsó,
• Gyula Simig,
• György Tibor Balogh and
• Balázs Volk

Beilstein J. Org. Chem. 2025, 21, 2220–2233, doi:10.3762/bjoc.21.169

• transferred to LC vials and stored at −20 °C until LC–MS/MS analysis. The concentration of the parent compound remaining in each sample was determined using liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS). The percentage of the remaining substrate was calculated relative to the time

Switchable pathways of multicomponent heterocyclizations of 5-amino-1,2,4-triazoles with salicylaldehydes and pyruvic acid

• Yana I. Sakhno,
• Oleksander V. Buravov,
• Kostyantyn Yu. Yurkov,
• Anastasia Yu. Andryushchenko,
• Svitlana V. Shishkina and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2025, 21, 2030–2035, doi:10.3762/bjoc.21.158

• control of the reaction, while oxygen-bridged heterocycles 4 are formed under thermodynamic control. The purity and structure of compounds 4 and 5 were established by elemental analysis, mass spectrometry, 1H and 13C NMR spectroscopy, and X-ray diffraction study (Figure 1). For example, the 1H NMR spectra