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

• condensation reactions involving rhodanine derivatives (26 examples). In addition, it requires a lower catalyst loading (10 mol %) and eliminates the need for further purification steps. EDDA has also been employed in reactions for the synthesis of heterocyclic compounds such as tetrahydroquinolines [67

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

• purification, all cyclopeptides were obtained in 45–70% isolated yields. Structural identities were confirmed by HRESIMS, NMR, and HPLC (>95% purity). Circular dichroism (CD) spectroscopy revealed distinct secondary structures, including β-sheets (1, 2, 3, 4, 7, 8, 10) and α-helical elements (5, 6). This

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

• to SG not only by electrostatic interactions but also covalently, the BU1 synthesis is straightforward lacking difficult and time-consuming purification, and it is obtained in relatively high yield over 60%. Once BU1 was prepared, its covalent attachment on the surface of SG was achieved in two steps

• and used without further purification. Dodecakis(5-carboxypentyl)bambus[6]uril (BU1) was synthesized according to a previously published procedure [13]. Infrared spectra were recorded with an Alpha spectrophotometer (Bruker). Thermogravimetric analyses were done with a Netzsch STA 449C Jupiter and

Total syntheses of highly oxidative Ryania diterpenoids facilitated by innovations in synthetic strategies

• Zhi-Qi Cao,
• Jin-Bao Qiao and
• Yu-Ming Zhao

Beilstein J. Org. Chem. 2025, 21, 2553–2570, doi:10.3762/bjoc.21.198

• compound 115 and establishing the correct C6 configuration. This transformation represents the first reported example of a hydroxy-directed Mukaiyama hydration reaction. The C8 carbonyl group was then protected as its 1,3-dithiolane derivative by treatment with 1,2-ethanedithiol. Without purification, the

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

• position. Therefore, dihydroxylation [37] readily converted alkene 11 to diol 12 as a mixture of inseparable isomers. Without purification, oxidative cleavage with NaIO4 resulted in a compound with strong UV absorption, which was eventually identified as enone 14 (Scheme 3). It is assumed that the

• NaClO·5H2O, the in situ-generated nitrile N-oxide immediately underwent intramolecular dipolar cycloaddition to deliver the cycloadducts 18 in good yield as a mixture of two inseparable diastereoisomers. This telescoped step was readily performed on a gram scale without interrupted purification of the

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

• purchased from Sigma-Aldrich (Milan, Italy) and used without further purification. Human renal adenocarcinoma 786-O cells were obtained from the American Type Culture Collection (ATCC; Manassas, VA, USA). Cells (passages 2-10) were maintained at 37 °C (5% CO2) in RPMI 1640 medium, containing 10% FBS, 2 mM ʟ

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

• Synthesis and biophysical assays With Db1–Db3 monomers prepared, new nucleobases were incorporated into PNA oligonucleotides (PNA1–PNA3) via solid phase peptide synthesis using Fmoc chemistry on an Expedite 8909 DNA/RNA/PNA synthesizer and following established protocols [40]. Following purification by

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

• egg yolk phosphatidylcholine (EYPC), Dipalmitoylphosphatidylcholine (DPPC), and cholesterol, all obtained from Avanti Lipids. All buffer solutions were prepared using Milli-Q Water from a Barnstead™ Water Purification System. Molecular biology grade dimethyl sulfoxide was used for stock solutions of

Ex-situ generation of gaseous nitriles in two-chamber glassware for facile haloacetimidate synthesis

• Nikolai B. Akselvoll,
• Jonas T. Larsen and
• Christian M. Pedersen

Beilstein J. Org. Chem. 2025, 21, 2465–2469, doi:10.3762/bjoc.21.188

• is not easily done as the system is now under pressure. The chamber was then opened to release excess gas (on small scale) and the product in chamber B can be obtained by concentration and purification. The use of other bases than DBU, was also investigated. Similar to the synthesis of

• , as described by Schmidt [24]. The acetylated glucosyl trifluoroacetimidate 4 was synthesized in 66% yield (Figure 2). The slightly higher isolated yield is reflecting the higher stability of the product and hence an easier purification. The two-chamber method clearly works for the generation of

• were obtained when using purification by “dry column vacuum chromatography” [28], which allowed separation of anomers. In the seminal paper by Schmidt [29] dichloroacetimidates were also synthesized. They were described as too unreactive to be viable alternatives to the trichloro analogs. The synthesis

Transformation of the cyclohexane ring to the cyclopentane fragment of biologically active compounds

• Natalya Akhmetdinova,
• Ilgiz Biktagirov and
• Liliya Kh. Faizullina

Beilstein J. Org. Chem. 2025, 21, 2416–2446, doi:10.3762/bjoc.21.185

• 90% yield to (+)-stephadiamine (71). The authors noted that the identification of the structure of (+)-stephadiamine (71) was carried out without purification of the reaction mixture due to its instability on a silica gel column under acidic or basic conditions. Zhang et al. [47] proposed an

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

• purification techniques [62][63][64]. Synthesis of pyrrolo-isoxazolidines utilizing nitrosoarenes via the multicomponent strategy is indeed feasible [65][66]. In a similar manner, Chakraborty obtained diastereomer products, primarily in cis configuration, from the cycloaddition reaction of a fluoro or a furyl

• Chemistry, this study did not employ column chromatography for the isolation and purification of the products of interest from the reaction mixture. Otherwise, the yield of the reaction conducted in a castor oil medium would be similar to that of the other reactions. Furthermore, the rapid realization of

• potential environmental or health implications. Experimental All reagents and solvents were purchased from Merck (Merck, Darmstadt, Germany), Sigma-Aldrich (St. Louis, MO), or Acros Organics (Thermo Fisher Scientific, Geel, Belgium) and used without further purification. Thin-layer chromatography was

Rotaxanes with integrated photoswitches: design principles, functional behavior, and emerging applications

• Jullyane Emi Matsushima,
• Khushbu,
• Zuliah Abdulsalam,
• Udyogi Navodya Kulathilaka Conthagamage and
• Víctor García-López

Beilstein J. Org. Chem. 2025, 21, 2345–2366, doi:10.3762/bjoc.21.179

• acridane photoswitch directly into a crown ether macrocycle [82]. However, the synthesis proceeded with very low yield, and the small amount of rotaxane obtained was immediately converted to the acridinium form during purification. Attempts to regenerate the acridane were unsuccessful. Nevertheless, the

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

• and were used without further purification. H2 was synthesized according to a previously published procedure [39]. NMR spectra were measured on commercial spectrophotometers at 400 MHz for 1H and 100 MHz for 13C in trifluoroacetic acid with a capillary tube containing deuterated water (D2O) for

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

• the volatility of 13, the crude solution obtained after the workup (quenching and phase separation) was directly used in the subsequent reaction without purification. Esterification of (2S,3S)-13 with p-nitrobenzoyl chloride (PNBCl) afforded PNB ester (2S,3S)-8 in 45% yield for two steps

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

• avoiding excess reagent, and simplifies purification and scale-up. With the most suitable reaction conditions in hand, the substrate scope was examined. First, the reactivity of different aryl bromides with phenylhydrazine (1a) to form non-symmetric azobenzene was explored (Scheme 1). Most of 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

• KGaA, Darmstadt, Germany), adjusting the pH with HCl. Water for buffer and eluent preparation were provided by a Millipore Milli-Q water purification system. Kinetic aqueous solubility assay. All compounds were dissolved in DMSO to make stock solutions at 10 mM concentration. In the case of 7i, 7j, and

• to LC–MS). Pure (E)-7h was obtained by purification using flash chromatography (hexane–EtOAc). Yield: 45 mg (40%), colorless crystals. Mp 138–139 °C (EtOH); 1H NMR (600 MHz, DMSO-d6) δ 9.54 (br s, 1H), 7.80 (d, J = 8.6 Hz, 1H), 7.62 (m, 2H), 7.57 (m, 2H), 7.54 (m, 3H), 6.71 (d, J = 7.7 Hz, 1H), 3.47

• ). Pure (Z)-7h was obtained by purification using flash chromatography (hexane–EtOAc). Yield: 17 mg (15%), pale yellow crystals. Mp 145–146 °C (EtOH); 1H NMR (600 MHz, DMSO-d6) δ 9.38 (br s, 1H), 7.84 (d, J = 8.5 Hz, 1H), 7.69 (m, 1H), 7.59 (m, 2H), 7.55 (m, 3H), 6.81 (d, J = 7.7 Hz, 1H), 6.77 (t, J = 5.2

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

• used without further purification. Melting points were obtained with a Mel-Temp capillary apparatus and were not corrected. IR spectra were obtained as KBr disks on a JASCO FT/IR-410 spectrophotometer. The FAB mass spectra were recorded using a JEOL 600H mass spectrometer. 1H and 13C{1H} NMR spectra

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

• . After evaporation of the solvent MeOH, the residue was redissolved in 2 mL of MeCN and heated at 130 °C for 2 h in a sealed vial to give product 7a in 90% yield after purification via Cu-free intramolecular click reaction (Scheme 3C) [46]. This Cu-free intramolecular cyclization provides key practical

Multicomponent reactions IV

• Thomas J. J. Müller and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2025, 21, 2082–2084, doi:10.3762/bjoc.21.163

• intermediate purification, work-up, or solvent exchange. Domino processes [3] are characterized by the simultaneous presence of all reactants from the outset, whereas sequential reactions permit the controlled addition of components while maintaining the same reaction conditions. Consecutive processes, in turn

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

• further purification after filtration. The use of starting components containing highly reactive groups, for example, an azide group, in the Ugi reaction provides opportunities for various post-cyclizations to obtain nitrogen-containing heterocyclic systems with potential biological activity [18]. To

Photochemical reduction of acylimidazolium salts

• Michael Jakob,
• Nick Bechler,
• Hassan Abdelwahab,
• Fabian Weber,
• Janos Wasternack,
• Leonardo Kleebauer,
• Jan P. Götze and
• Matthew N. Hopkinson

Beilstein J. Org. Chem. 2025, 21, 1973–1983, doi:10.3762/bjoc.21.153

• higher reduction potential of this comparatively electron-rich compound. Purification of the crude reaction mixture from 1 by column chromatography allowed for the isolation of pure product 5 as a colorless oil in 59% yield. A control reaction performed under the same conditions in the dark resulted only

Rhodium-catalysed connective synthesis of diverse reactive probes bearing S(VI) electrophilic warheads

• Scott Rice,
• Julian Chesti,
• William R. T. Mosedale,
• Megan H. Wright,
• Stephen P. Marsden,
• Terry K. Smith and
• Adam Nelson

Beilstein J. Org. Chem. 2025, 21, 1924–1931, doi:10.3762/bjoc.21.150

• diverse co-substrates. A high-throughput approach was used to identify promising substrate/co-substrate/catalyst combinations which were then prioritised for purification by mass-directed HPLC to yield a total of thirty reactive probes. The structural diversity of the probe set was increased by the

• reactions, a product with molecular weight consistent with O–H insertion into water was also observed. For these 18 substrate/co-substrate combinations, the reaction with the highest estimated yield was selected for mass-directed purification (Table 2). In total, 23 intermolecular reaction products were

• tag (C17 and C18) were used. The reactions were assembled from stock solutions, with some variation in stock concentrations to improve solubility. After 24 h, the reaction products were analysed by LC–MS, and promising reactions selected for mass-directed purification. Seven additional intermolecular

Synthesis, biological and electrochemical evaluation of glycidyl esters of phosphorus acids as potential anticancer drugs

• Almaz A. Zagidullin,
• Emil R. Bulatov,
• Mikhail N. Khrizanforov,
• Damir R. Davletshin,
• Elvina M. Gilyazova,
• Ivan A. Strelkov and
• Vasily A. Miluykov

Beilstein J. Org. Chem. 2025, 21, 1909–1916, doi:10.3762/bjoc.21.148

• (O)Cl3 and glycidol were purchased from suppliers and used without additional purification. Synthesis of diglycidyl methylphosphonate (1). A 500 mL flask with 200 mL of dichloromethane, equipped with a mechanical stirrer, was cooled to −30 °C. Then, 2 equiv of glycidol (21.4 g, 0.289 mol) and 4.2

Preparation of spirocyclic oxindoles by cyclisation of an oxime to a nitrone and dipolar cycloaddition

• Beth L. Ritchie,
• Alexandra Longcake and
• Iain Coldham

Beilstein J. Org. Chem. 2025, 21, 1890–1896, doi:10.3762/bjoc.21.146

• bridged azabicyclic ring system found in alstonoxine A and related alkaloids. Experimental Chemicals described were obtained from commercial suppliers and were used without further purification. Solvents were obtained from a Grubbs dry solvent system. Thin-layer chromatography was performed on Merck

Photoswitches beyond azobenzene: a beginner’s guide

• Michela Marcon,
• Christoph Haag and
• Burkhard König

Beilstein J. Org. Chem. 2025, 21, 1808–1853, doi:10.3762/bjoc.21.143