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

• and 4n During the characterization of the compounds obtained in our study to determine the reaction scope, an anomaly was observed in the NMR spectra of products 3n and 4n derived from 4-diethylaminobenzaldehyde (see Supporting Information File 1). The spectra were acquired at 600 MHz for 1H NMR (320

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

• RP-HPLC. This optimized protocol afforded segetalins A–H, J and K (1–10) with 45% to 70% isolated yields (Figure 1). Structural characterization The synthetic compounds 1–10 were rigorously characterized to confirm their identity and purity (see Supporting Information File 1). High-resolution

• reagent for the challenging head-to-tail macrocyclization step under moderate dilution (10−3 M). This protocol afforded the target cyclic peptides in practical isolated yields (45–70%) and high purity. Comprehensive structural characterization by HRESIMS, NMR, and HPLC confirmed the identity and high

• Information File 8: Experimental section, characterization and copies of spectra. Funding We are grateful to National Natural Science Foundation of China (U23A20524 & 22271126), Gansu Provincial Science and Technology Leading Talents Program (24RCKB005) and Gansu Science and Technology Program (25JRRA695).

Silica gel with covalently attached bambusuril macrocycle for dicyanoaurate sorption from water

• Michaela Šusterová and
• Vladimír Šindelář

Beilstein J. Org. Chem. 2025, 21, 2604–2611, doi:10.3762/bjoc.21.201

• solution (10 mM) for 1 h or 3 × 15 min; experiments were done using 50 mg of SG-NHCO-BU1. Synthesis of SG-NHCO-BU1 and SG-BU1 materials based on covalently and non-covalently attached BU1 on the SG surface. Supporting Information Supporting Information File 4: Characterization of materials and additional

Ni-promoted reductive cyclization cascade enables a total synthesis of (+)-aglacin B

• Si-Chen Yao,
• Jing-Si Cao,
• Jian Xiao,
• Ya-Wen Wang and
• Yu Peng

Beilstein J. Org. Chem. 2025, 21, 2548–2552, doi:10.3762/bjoc.21.197

• structures of aglacins A, B, C, and E. Retrosynthetic analysis of (+)-aglacin B (2). Synthesis of cyclization precursor 5. Synthesis of (+)-aglacin B (2). Supporting Information Supporting Information File 16: Experimental procedures, characterization data, and copies of 1H/13C NMR spectra

Rapid access to the core of malayamycin A by intramolecular dipolar cycloaddition

• Yilin Liu,
• Yuchen Yang,
• Chen Yang,
• Sha-Hua Huang,
• Jian Jin and
• Ran Hong

Beilstein J. Org. Chem. 2025, 21, 2542–2547, doi:10.3762/bjoc.21.196

• the Baeyer–Villiger reaction. Supporting Information Supporting Information File 14: Experimental procedures and compound characterization data. Acknowledgements We thank Dr. Min Shao (Shanghai University) for assistance of X-ray analysis. Funding Financial support from the National Natural Science

Synthesis and characterization of a isothiouronium-calix[4]arene derivative: self-assembly and anticancer activity

• Giuseppe Granata,
• Loredana Ferreri,
• Claudia Giovanna Leotta,
• Giovanni Mario Pitari and
• Grazia Maria Letizia Consoli

Beilstein J. Org. Chem. 2025, 21, 2535–2541, doi:10.3762/bjoc.21.195

• , and low toxicity make calixarene derivatives valuable drug candidates against cancer. The aim of the present study was the synthesis and characterization of a calix[4]arene derivative in which known anticancer isothiouronium groups were clustered on a calix[4]arene scaffold bearing long C12 alkyl

• anticancer activity. The synthesis and structural characterization of compound 3 were carried out, and its self-assembly behavior in aqueous medium was investigated using dynamic light scattering (DLS) and electrophoretic light scattering (ELS). The anticancer potential of compound 3 was assessed in human

• and characterization of compound 3 For the synthesis of isothiouronium-calix[4]arene derivative 3 (Scheme 1), the chloromethylcalix[4]arene derivative 2 was prepared by adopting a procedure reported in the literature [44]. In brief, starting from the commercial p-H-calix[4]arene 1, four C-12 alkyl

Pentacyclic aromatic heterocycles from Pd-catalyzed annulation of 1,5-diaryl-1,2,3-triazoles

• Kaylen D. Lathrum,
• Emily M. Hanneken,
• Katelyn R. Grzelak and
• James T. Fletcher

Beilstein J. Org. Chem. 2025, 21, 2524–2534, doi:10.3762/bjoc.21.194

• Supporting Information Supporting Information File 4: Description of materials, experimental methods, synthetic procedures, analytical characterization and copies of NMR spectra for novel compounds. Funding Research reported in this publication was supported by the National Institute of General Medical

Isoorotamide-based peptide nucleic acid nucleobases with extended linkers aimed at distal base recognition of adenosine in double helical RNA

• Grant D. Walby,
• Brandon R. Tessier,
• Tristan L. Mabee,
• Jennah M. Hoke,
• Hallie M. Bleam,
• Angelina Giglio-Tos,
• Emily E. Harding,
• Vladislavs Baskevics,
• Martins Katkevics,
• Eriks Rozners and
• James A. MacKay

Beilstein J. Org. Chem. 2025, 21, 2513–2523, doi:10.3762/bjoc.21.193

• calorimetry.c Supporting Information Supporting Information File 20: General synthetic details and procedures, characterization data for synthetic intermediates, biophysical assays, and computational details. Acknowledgements We thank Ilze Kumpina for help with the ITC data analysis. Funding This work was

Assembly strategy for thieno[3,2-b]thiophenes via a disulfide intermediate derived from 3-nitrothiophene-2,5-dicarboxylate

• Roman A. Irgashev

Beilstein J. Org. Chem. 2025, 21, 2489–2497, doi:10.3762/bjoc.21.191

• -nucleophiles to form sulfide 2 and disulfide 3. Optimization of the reaction conditions for the reduction–alkylation of disulfide 3. Supporting Information Supporting Information File 12: Full experimental details, characterization data, copies of NMR spectra and HRMS for all new compounds. Acknowledgements

Palladium-catalyzed regioselective C1-selective nitration of carbazoles

• Vikash Kumar,
• Jyothis Dharaniyedath,
• Aiswarya T P,
• Sk Ariyan,
• Chitrothu Venkatesh and
• Parthasarathy Gandeepan

Beilstein J. Org. Chem. 2025, 21, 2479–2488, doi:10.3762/bjoc.21.190

• of our method. Key mechanistic studies. Optimization studies.a Supporting Information Supporting Information File 9: Experiment details, characterization data, copy of NMR spectra of synthesized compounds, and single-crystal X-ray diffraction data. Supporting Information File 10: CIF file for 2a

Synthesis of the tetracyclic skeleton of Aspidosperma alkaloids via PET-initiated cationic radical-derived interrupted [2 + 2]/retro-Mannich reaction

• Ru-Dong Liu,
• Jian-Yu Long,
• Zhi-Lin Song,
• Zhen Yang and
• Zhong-Chao Zhang

Beilstein J. Org. Chem. 2025, 21, 2470–2478, doi:10.3762/bjoc.21.189

• along IRC path. e) Spin-density analyses of R-24 and F-10 (isovalue = 0.004). f) NBO analyses of the selected transient structures (isovalue = 0.04). Substrate scope. Conditions screening.a Supporting Information Supporting Information File 6: Experimental procedures, characterization data, NMR spectra

The high potential of methyl laurate as a recyclable competitor to conventional toxic solvents in [3 + 2] cycloaddition reactions

• Ayhan Yıldırım and
• Mustafa Göker

Beilstein J. Org. Chem. 2025, 21, 2389–2415, doi:10.3762/bjoc.21.184

• (cis + trans isomers). Catalyst survey for the synthesis of 3a (cis + trans isomers). Supporting Information Supporting Information File 4: Characterization data, copies of NMR spectra, additional Table and Figures. Funding We gratefully acknowledge the Bursa Uludağ University Scientific Research

An Fe(II)-catalyzed synthesis of spiro[indoline-3,2'-pyrrolidine] derivatives

• Elizaveta V. Gradova,
• Nikita A. Ozhegov,
• Roman O. Shcherbakov,
• Alexander G. Tkachenko,
• Larisa Y. Nesterova,
• Elena Y. Mendogralo and
• Maxim G. Uchuskin

Beilstein J. Org. Chem. 2025, 21, 2383–2388, doi:10.3762/bjoc.21.183

• mmol scale experiment. The scope of the Fe-catalyzed spirocyclization. aIsolated yield of the 4.2 mmol scale experiment. The proposed mechanism of product 4 formation. Supporting Information Supporting Information File 2: General reaction procedures, compound characterization data, and copies of NMR

Synthetic study toward vibralactone

• Liang Shi,
• Jiayi Song,
• Yiqing Li,
• Jia-Chen Li,
• Shuqi Li,
• Li Ren,
• Zhi-Yun Liu and
• Hong-Dong Hao

Beilstein J. Org. Chem. 2025, 21, 2376–2382, doi:10.3762/bjoc.21.182

• . Supporting Information Supporting Information File 34: Characterization data and 1H NMR, 13C NMR spectra of the compounds. Acknowledgements The authors sincerely acknowledge all of the anonymous reviewers for their valuable comments and suggestions. Funding We are grateful for financial support from the Qin

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

• (Figure S3) in Supporting Information File 1. WDG exhibited poor solubility, which hindered the direct acquisition of its single crystal structure for characterization. However, after Boc (tert-butyloxycarbonyl) protection, a single crystal structure (CCDC Number: 2339028) of the modified compound was

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

• environmental concern. We report the design, synthesis, and characterization of a series of methylene-bridged glycoluril dimers G2W1–G2W4 that are insoluble in water and that differ in the nature of their aromatic sidewalls (G2W4: benzene, G2W3: naphthalene, G2W1 and G2W2: triphenylene). We tested G2W1–G2W4

• section is organized as follows. First, we present the design, synthesis, and characterization of two new aromatic walls W1 and W2 (Scheme 1) and four new water-insoluble acyclic CB[n] hosts G2W1–G2W4 (Scheme 2). Next, we study the impact of different aromatic side walls on the removal of five dyes

• violet removal efficiency using triphenylene-walled G2W1. Design, synthesis and characterization of G2W1–G2W4 The sequestration of large planar aromatic dyes from aqueous solution into the solid state requires water-insoluble hosts that possess complementary molecular recognition surfaces. Previously, we

Halogenated butyrolactones from the biomass-derived synthon levoglucosenone

• Johannes Puschnig,
• Martyn Jevric and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2025, 21, 2297–2301, doi:10.3762/bjoc.21.175

• fluorination attempts. Maintaining some residual solvent allowed for the characterization of compound 13 by NMR spectroscopy. Stereochemical assignment in 13 was based on a large trans-axial coupling constant JH2exo-H3 = 10.6 Hz in the 1H NMR spectrum and interactions between H3endo and H7endo on the

• File 28: Experimental section, characterization data and copies of spectra. Funding J.P. thanks the Australian Government for a Research Training Program (RTP) Scholarship and a Destination Australia Program (DAP) scholarship.

Pd-catalyzed dehydrogenative arylation of arylhydrazines to access non-symmetric azobenzenes, including tetra-ortho derivatives

• Loris Geminiani,
• Kathrin Junge,
• Matthias Beller and
• Jean-François Soulé

Beilstein J. Org. Chem. 2025, 21, 2234–2242, doi:10.3762/bjoc.21.170

• from phenylhydrazine and aryl bromides. The gray box provides a detailed list of all identified side-products. Supporting Information Supporting Information File 20: Details of optimization experiments, full characterization data, and NMR spectra (1H, 13C, 19F) for all products. Funding L.G

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

• variety of new tri-, tetra- and pentacyclic ring systems. The structural characterization of (E)- and (Z)-hydrazones was supported by 2D NMR techniques, while that of the target compounds by single-crystal X-ray measurements. The hydrazone intermediates and the new title compounds were subjected to a

• physicochemical and early ADME characterization study, in the framework of which logP, pKa and logk values were calculated. Following that, kinetic solubility and in vitro gastrointestinal membrane-specific permeability measurements were carried out to assess the lead-likeness of the compounds. Subsequently, the

• metabolic stability of the most promising derivatives was also determined using human liver microsomes. Keywords: early ADME characterization; Fischer indole cyclization; heterocycles; indoles; lead-likeness; new ring systems; physicochemical characterization; Introduction Considering the published

A m-quaterphenyl probe for absolute configurational assignments of primary and secondary amines

• Yuka Takeuchi,
• Mutsumi Kobayashi,
• Yuuka Gotoh,
• Mari Ikeda,
• Yoichi Habata,
• Tomohiko Shirai and
• Shunsuke Kuwahara

Beilstein J. Org. Chem. 2025, 21, 2211–2219, doi:10.3762/bjoc.21.168

• central biphenyl moiety rotates freely, forming an equilibrium mixture of P and M conformers. Supporting Information Supporting Information File 9: Experimental procedures, characterization data including copies of NMR spectra (1H NMR, 13C NMR), CD spectra of (S)-2f and (R)-2f, theoretical calculations

Synthesis of triazolo- and tetrazolo-fused 1,4-benzodiazepines via one-pot Ugi–azide and Cu-free click reactions

• Xiaoming Ma,
• Zijie Gao,
• Jiawei Niu,
• Wentao Shao,
• Shenghu Yan,
• Sai Zhang and
• Wei Zhang

Beilstein J. Org. Chem. 2025, 21, 2202–2210, doi:10.3762/bjoc.21.167

• one-pot synthesis of 8a. Supporting Information Supporting Information File 6: Experimental section, characterization data and copies of spectra.

C2 to C6 biobased carbonyl platforms for fine chemistry

• Jingjing Jiang,
• Muhammad Noman Haider Tariq,
• Florence Popowycz,
• Yanlong Gu and
• Yves Queneau

Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165

Further elaboration of the stereodivergent approach to chaetominine-type alkaloids: synthesis of the reported structures of aspera chaetominines A and B and revised structure of aspera chaetominine B

• Jin-Fang Lü,
• Jiang-Feng Wu,
• Jian-Liang Ye and
• Pei-Qiang Huang

Beilstein J. Org. Chem. 2025, 21, 2072–2081, doi:10.3762/bjoc.21.162

• procedures, characterization data, and copies of 1H and 13C NMR spectra of compounds 19/20, 25, 26, 12, 13, and 6. Acknowledgements We thank Ms. Yan-Jiao Gao for technical assistance. Funding We are grateful for financial support of this work from the National Natural Science Foundation of China (22571267

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

• -amino-5-methylthio-1,2,4-triazole (1a), salicylaldehydes 2a–c,f, and pyruvic acid (3) under different conditions. Synthesis of compounds 4a–j. Synthesis of compounds 5a–c. Supporting Information Supporting Information File 34: Experimental procedures, product characterization, and copies of NMR spectra

α-Ketoglutaric acid in Ugi reactions and Ugi/aza-Wittig tandem reactions

• Vladyslav O. Honcharov,
• Yana I. Sakhno,
• Olena H. Shvets,
• Vyacheslav E. Saraev,
• Svitlana V. Shishkina,
• Tetyana V. Shcherbakova and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2025, 21, 2021–2029, doi:10.3762/bjoc.21.157

• /aza-Wittig combination involving KGA. Yields of compounds 5a–l. Yields of compounds 6a–d. Yields of compounds 8a,b,d,f–h and 9a–h. Supporting Information Supporting Information File 32: General synthetic procedures, characterization of compounds, 1H and 13C NMR spectra and X-ray data