Halogenated azobenzene acrylates: from efficient solution photoswitching to stable solid-state photochromic materials

• Martina Vachtlová,
• Michaela Fecková,
• Vítězslav Zima,
• Jan Podlesný,
• Milan Klikar,
• Oldřich Pytela,
• Patrik Pařík,
• Jakub Opršal,
• Eliška Juhaňáková,
• Veronika Chrtová and
• Filip Bureš

Beilstein J. Org. Chem. 2026, 22, 782–794, doi:10.3762/bjoc.22.60

• liquid crystalline copolymeric pendants in macromolecules capable to change their reflectance with the temperature. This feature potentially enables their usage in temperature sensing labels [22]. These representative applications clearly demonstrate a wide interest in a light-driven control over the

Design, synthesis, and biological evaluation of FXR/ASK1 dual-target modulators

• Xi Zhang,
• Jingyan Wang,
• Ziqiang Zhao,
• Caiyi Wang,
• Zenghui Ye,
• Wei-Yuan Ma,
• Jian-Xing Xu and
• Fengzhi Zhang

Beilstein J. Org. Chem. 2026, 22, 771–781, doi:10.3762/bjoc.22.59

• accumulation. The presence of lipid droplets was confirmed through direct visualization using Oil Red O staining (Figure 3A). The combined treatment with GW4064 and GS4997 exerted a stronger lipolytic effect than either positive control alone, and its activity was comparable to that of Z8. As anticipated, both

• -luciferase reporter assay in CHO cells cultured for 24 hours following addition of GW4064 and test compounds. Compared to the control group, **p < 0.01 and ns indicate no significant difference, with control; DMSO serving as the control group. ASK1 inhibition of all compounds. Results of the ADP-Glo™ kinase

• assay after treating ASK1 kinase with selonsertib and test compounds for 1 hour. Compared to the control group: **p < 0.01 and ns indicates no significant difference; control: DMSO control group. Effects of Z8 and Z30 on OA-induced lipid accumulation in HepG2 cells. Cells were treated with GW4064

Synthesis and biological evaluation of new brassinosteroid analogs with C-22 benzoate function

• María Núñez,
• Camila Escobar,
• Mario Párraga,
• Mauricio Soto,
• Luis Espinoza-Catalán,
• Katy Díaz and
• Andrés F. Olea

Beilstein J. Org. Chem. 2026, 22, 753–762, doi:10.3762/bjoc.22.57

• -carbonyl or 3β-hydroxy function in this ring. Additionally, the accumulation of the dephosphorylated form of the BES1 protein, which is part of the BRs signaling pathway and control their activity, has been evaluated as well. The results are analyzed in terms of BR analog’s structure and compared with

• –22 have been measured at different concentrations (Table S1, Supporting Information File 1). The activities, calculated as the difference of bending angles obtained for the analogs and the negative control, and normalized respect to the latter, are shown in Table 1. The data show that the plant

• response to exogenous application of brassinolide (1) (positive control) or synthetic BR analogs strongly depends on the chemical structure of the BRs. For example, the activity increases with increasing concentration of 1, and analogs 18, 20 and 22, whereas the opposite effect is obtained by applying

Rongalite addition to dienones: diastereoselectivity in cyclic sulfone synthesis; stereochemical rationalization and prospects as a general conjugate nucleophile

• Melina Goga,
• Hao Zong,
• James Franco,
• Jazmine Prana,
• Rudolph Michel,
• Antonia Muro,
• Elana Rubin,
• Janet Brenya,
• Henk Eshuis and
• Magnus W. P. Bebbington

Beilstein J. Org. Chem. 2026, 22, 742–752, doi:10.3762/bjoc.22.56

• sulfide oxidation. In that early work, the stereochemical analysis was dependent on conformational analysis and comparison of coupling constants in the 1H NMR spectra. Experiments discussed in our inital report confirmed that the reaction proceeded under kinetic control [21]. Closer examination of the

• 20, in contrast to the successful reaction with phorone (21) to give 22 [43] (Scheme 4). As a control reaction, we conducted the addition of commercially available sodium p-toluenesulfinate to mesityl oxide under analogous conditions, which produced known sulfone 23 [44] in high yield. This

• selectivity for formation of 26 at room temperature suggests a profile that is more reflective of kinetic control, such that we can argue that 26 forms between 1 and 2 orders of magnitude more rapidly than cyclic products 1a and 1b, such that they are not detectable in the 1H NMR spectra. Further anecdotal

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

• chiral metal complexes of Ag(I), Cu(I/II), Zn(II), Ni(II) with ligands of the Segphos, Fesulfos, or Biphamphos type [12][13][14][15]. Such catalytic systems control the enantioselectivity of cycloaddition and allow the preparation of enantioenriched pyrrolidines containing several stereocenters in high

• reactions is due to charge and orbital control [1]. Continuing the study of 1,3-dipolar cycloaddition reactions of ninhydrin-based azomethine ylides with cyclopropene dipolarophiles, our research group examined the interaction of cyclopropenes with azomethine ylides from ninhydrin and acyclic amino acids

• of regio- and endo-stereoselective spiro- and dispiro-derivatives of azabicyclo[3.2.0]heptane 151 and 152 is due to orbital control along with second orbital interactions [101]. In 2015, Wu and co-workers described a multicomponent synthesis of various spiro[indole-pyrrolizine], spiro[indole

Anti-invasive and cytotoxic evaluation of a (+)-pinoresinol-based semisynthetic library against glioblastoma

• Chen Zhang,
• Kah Yean Lum,
• Jonathan M. White,
• Paul I. Forster,
• Nicholas Booth,
• Sunita A. Ramesh and
• Rohan A. Davis

Beilstein J. Org. Chem. 2026, 22, 691–704, doi:10.3762/bjoc.22.54

• ranging from 1.56−25 µM with a reduction of up to 65% invasion in comparison to the control [22]. Owing to the interesting biological activity of 2 and its moderate abundance in the seeds of E. maculata, we decided to generate five semisynthetic analogues 3−7 (Figure 2) and evaluate these compounds for in

• concentration of 1 µM with a treatment time of 5 h, and only (+)-4,4'-di(3,3-dimethylbutanoyl)pinoresinol (6) reduced the invasion of the cells (by ≈50%) when compared to the vehicle control. None of the other compounds tested reduced the invasive capability of the cells (Figure 7A). Based on the results of the

• to achieve a cell number of 15,000 cells per mL. Cells were seeded in a 96-well plate (Costar #3596) in triplicates at 100 µL/well (i.e., 1,500 cells/well) and incubated for 24 h at 37 °C and 5% CO2. Vehicle control (positive control) was the solvent DMSO, in which all compounds were dissolved, plus

Harnessing light energy with molecules

• Grace G. D. Han,
• Mogens Brøndsted Nielsen and
• Hermann A. Wegner

Beilstein J. Org. Chem. 2026, 22, 680–682, doi:10.3762/bjoc.22.52

• larger systems or smart materials [9]. Photoswitches are, for example, relevant functional units for information storage or molecular electronic devices. They can serve to control ion transport, molecular assembly/disassembly, or the relative movement of units within molecular machines. In a Review

Photoorganocatalytic trifluoromethylation of (het)arenes in green conditions

• Egor N. Boronin,
• Svetlana E. Kaurkina,
• Milena M. Svetlakova,
• Anton S. Bolshakov,
• Maxim V. Arsenyev,
• Vasilii F. Otvagin,
• Alexey Yu. Fedorov,
• Timothy Noël and
• Alexander V. Nyuchev

Beilstein J. Org. Chem. 2026, 22, 662–671, doi:10.3762/bjoc.22.50

• protocol [16]. Finally, a series of control experiments was carried out. No product formation was observed in the absence of catalyst (Table 1, entry 11), in the dark (entry 12), in the presence of TEMPO (entry 13), or under an air atmosphere (entry 14). Based on the optimization studies, the standard

Advantages of PROTACs in achieving selective degradation of homologous protein families

• Luxi Yang,
• Xinfei Mao,
• Jingyi Zhang,
• Jing Shu,
• Wenhai Huang,
• Xiaowu Dong,
• Yinqiao Chen and
• Mingfei Wu

Beilstein J. Org. Chem. 2026, 22, 628–661, doi:10.3762/bjoc.22.49

• nanomolar range, the DC50 values for BRD2/3 were both well above 100 nM. Due to the conformational constraint imposed by the macrocyclic linker, compound 37 did not exhibit a "hook effect" even at concentrations as high as 60 μM, whereas the linear control molecule 35 showed a decline in activity at 30 μM

• life to control the disease's further deterioration. Based on these circumstances, if the PROTAC technology can be used to target the degradation of the BCR-ABL protein, it may maintain a good therapeutic effect for CML and reduce the time for CML patients to take medicine. Therefore, to achieve good

Regioselective approach to 5-arylsulfonylisoxazoles and their antimicrobial activity

• Artem S. Sazonov,
• Dmitry A. Vasilenko,
• Denis V. Porfiriev,
• Yuri K. Grishin,
• Rimma A. Gazzaeva,
• Alisa P. Chernyshova,
• Maxim A. Kryakvin,
• Anna A. Baranova,
• Vera A. Alferova and
• Elena B. Averina

Beilstein J. Org. Chem. 2026, 22, 592–602, doi:10.3762/bjoc.22.45

• nitrile oxides in cycloaddition reactions, complete control of regioselectivity without metal catalysis is not always achievable. Another problem with this method is the tendency of nitrile oxides to form dimers (furoxanes), which entails a decrease in the yield of isoxazoles. Due to dimerization, nitrile

• stalled replication forks and impaired DNA synthesis. This disruption triggers cell cycle arrest, which can ultimately result in apoptosis and cell death. However, all tested samples 3h, 3g and 4b exhibited no significant difference compared to the control lane (Figure 3B), indicating that they did not

• passage of the strands through the break and subsequent ligation, leading to DNA relaxation. DNA gyrase performs a similar function but without the requirement for ATP hydrolysis. The antibiotic ciprofloxacin (Cip), which inhibits DNA gyrase, was used as the positive control. In this test, all tested

Continuous-flow carbonyl hydrogenation under subatmospheric to atmospheric hydrogen pressure enabled by robust heterogeneous Pt–Fe catalysts

• Hiroyuki Miyamura,
• Ryosuke Kajiyama,
• Shun-ya Onozawa,
• Yoshihiro Kon and
• Shū Kobayashi

Beilstein J. Org. Chem. 2026, 22, 575–582, doi:10.3762/bjoc.22.43

• ][10][11][12]. In this context, advanced technologies represented by the precise control of the bimetallic structure of a heterogeneous catalyst, mechanochemical hydrogenation, and continuous-flow methods using packed-bed reactors greatly contributed to advancing this transformation [9][11][12][13

• column with Celite, with the molar amount of Pt adjusted to 0.006 mmol within the column. Both the solution of acetophenone (1a) in ethyl acetate (EtOAc) and hydrogen gas were simultaneously passed through the catalyst-packed column without backpressure control at room temperature (Scheme 1). The powder

Kinetic resolution of racemic planar-chiral vinylcymantrenes by molybdenum-catalyzed asymmetric metathesis dimerization

• Haruna Imazu,
• Hitoshi Izu,
• Yasuhiro Ohki and
• Masamichi Ogasawara

Beilstein J. Org. Chem. 2026, 22, 568–574, doi:10.3762/bjoc.22.42

• ], reveals that the molybdenum-catalyzed asymmetric metathesis reactions are powerful tools to control planar chirality in various transition-metal complexes. ORTEP drawing of the X-ray structure of (S,S)-(–)-2b with atom numbering (thermal ellipsoids set at the 30% probability level). Selected bond lengths

Molecular tweezer–peptide conjugates disrupt the protein–protein interaction between survivin and histone H3 essential in mitosis

• Catherine Gsell,
• Philipp Rebmann,
• Karina Opara,
• Christine Beuck,
• Peter Bayer,
• David Bier,
• Ingrid R. Vetter and
• Thomas Schrader

Beilstein J. Org. Chem. 2026, 22, 557–567, doi:10.3762/bjoc.22.41

• centromere protein), and the kinase Aurora B. During mitosis, Aurora B phosphorylates important components of the kinetochore and thus exerts control over key events of the whole process. The other three proteins localize the CPC during the different mitotic phases [4]. Survivin, borealin and INCENP are

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

• mixture of melifolione A (1) and B (2) (181 mg, 0.6 mmol, ratio ca. 10:1) was dissolved in 16 mL acetonitrile. After addition of water (4 mL), the solution was cooled on ice and iodosobenzene diacetate (212 mg, 0.66 mmol) was added under stirring. The solution turned yellow and later orange. TLC control

Recent advances in the stereoselective synthesis of distal biaxially chiral molecules

• Fanxing Zhou,
• Chen Zhang,
• Lingyu Sun,
• Yiyun Fang,
• Siming Zheng,
• Lina Hu,
• Mengyang Shen,
• Zhen Zhao,
• Wei Xu,
• Yunqiang Sun and
• Zi-Qiang Rong

Beilstein J. Org. Chem. 2026, 22, 461–479, doi:10.3762/bjoc.22.34

• often difficult to control [37], particularly for remote biaxial systems (1,3-biaxial and beyond), where diastereoselectivity and enantioselectivity are challenging to regulate. Various multiaxial chiral natural products with high biological activity exist in nature [28], and in artificial synthesis

• construction of remote biaxial chiral molecules. These strategies enable precise control over the stereochemistry of multiple axes in a single reaction, allowing efficient formation of distal biaxial chiral scaffolds while maintaining excellent enantio- and diastereoselectivity. Recent studies have

• exceeding 60%. Sequential construction of distal biaxial chirality via stepwise axis formation Although one-step catalytic methods enable the efficient and direct construction of remote biaxially chiral molecules, the spatial interactions between multiple chiral axes can make it challenging to fully control

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

• viability, one-way ANOVA was performed using GraphPad Prism software [64], as shown in Figure 8, comparing the control group to each test concentration of the compound 7 (Figure 8a) and compound 8 (Figure 8b). The results showed no significant differences between the control and 6.12 µM concentrations

• dissolved in DMSO and administered at concentrations of 6.27, 12.5, 25, 50, 100, and 200 μM, along with a control group. All treatments were performed in triplicate to minimise analytical and experimental errors. Cells were cultured for a further 24 hours under the same conditions following chemical

• concentration (µM) vs cell viability (%) of compounds of a) 7 and b) 8. Significant difference of control vs concentration: a) compound 7, b) compound 8. 2D and 3D binding interaction of active (1M17) EGFR tyrosine kinase and synthesised compounds: a) 7 and b) 8, c) 2D interaction of crystal structure 1M17 and

Cone p-aminocalix[4]arenes enriched with ‘clickable’ alkyne or azide functionalities

• Ilia Korniltsev,
• Vasily Bazhenov,
• Alexander Gorbunov,
• Dmitry Cheshkov,
• Stanislav Bezzubov,
• Vladimir Kovalev and
• Ivan Vatsouro

Beilstein J. Org. Chem. 2026, 22, 399–415, doi:10.3762/bjoc.22.28

• atoms and/or in the aromatic p-positions to them, which form respectively the narrow (lower) and wide (upper) rims of the calixarene macrocycle when it possesses a cone shape. Both the core functionalization and shape control strategies are most developed for calix[4]arene cores, and that is exactly why

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

• and 1% penicillin/streptomycin mixture, for obtaining concentrations ranging from 0.1 to 1000 µM. All experiments were carried out in triplicate, and the data are presented as mean ± standard deviation. Paclitaxel (PTX) was used as positive control. Compounds-treated and untreated cells were incubated

Electrosynthetic access to unsymmetrical oxaza[8]helicenes with high chiral stability and strong circularly polarized luminescence (CPL)

• Tin Zar Aye,
• Rubal Sharma,
• Muthu Karuppasamy,
• Daiya Suzuki,
• Haruka Nakajima,
• Yoshitane Imai,
• Mitsuhiro Arisawa,
• Mohamed S. H. Salem and
• Shinobu Takizawa

Beilstein J. Org. Chem. 2026, 22, 372–382, doi:10.3762/bjoc.22.25

• is often hindered by chemoselectivity and regioselective control. Here, we exploit the differential redox potentials of two coupling partners as a key player to achieve a chemo- and regioselective electrosynthetic access to a new family of unsymmetrical oxaza[8]helicenes. A controlled anodic sequence

• electrochemical arenol activations reported by Waldvogel and co-workers [46]. Subsequent intramolecular dehydrative cyclization furnishes the desired oxaza[8]helicenes 5. The oxidation-potential gap between 3 and 4 and the reactivity of Int-I thus provides a handle to control chemo- and regioselectivity

• designed coupling partners to control both chemo- and regioselectivity. A finely tuned anodic sequence enables selective oxidative hetero-coupling followed by dehydrative cyclization, delivering extended [8]helical scaffolds efficiently under mild, oxidant-free conditions. Combined experimental and DFT

Non-central chirality in organic chemistry

• Ken Tanaka and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2026, 22, 370–371, doi:10.3762/bjoc.22.24

• commonality lies in how chirality emerges from extended molecular frameworks, dynamic conformational landscapes, or topological constraints. As such, non-central chirality challenges both our synthetic capabilities and our conceptual understanding of stereochemical control. Numerous reviews have addressed

Recent advances in the cleavage of non-activated amides

• Eun-Sol Choi and
• Hyo-Jun Lee

Beilstein J. Org. Chem. 2026, 22, 352–369, doi:10.3762/bjoc.22.23

• bioactive compounds underwent smooth esterification with TFE to give the corresponding 2,2,2-trifluoroethyl esters 82–85 in high yields. To elucidate the reaction mechanism, cyclic voltammetry experiments, control reactions, and DFT calculations were conducted. At the anode, bromide ions are oxidized to

Spirobarbiturates with a pyrrolizidine moiety: synthesis, structure and biological evaluation

• Arthur A. Puzyrkov,
• Andrew S. Drachuk,
• Ekaterina A. Popova,
• Alexander V. Stepakov and
• Vitali M. Boitsov

Beilstein J. Org. Chem. 2026, 22, 274–288, doi:10.3762/bjoc.22.20

• , 4k and 4l was equal to 25, 19, 31, 21, 23, and 19% for the tested compounds and control sample, respectively. As can be seen from the obtained data the wound healing ability are consistent with the cytoskeleton data. Compounds 4g and 4l, which led to less stress fibers (87 ± 22%, 71 ± 16% vs 46 ± 7

• % for 4g, 4l vs control, respectively) and nearly the same filopodia-like deformations (35 ± 15% and 36 ± 22% vs 33 ± 17% for 4g and 4l vs control, respectively) as compared to the control, result in low wound healing ability when applied to Sk-mel-2 cells. At the same time, compound 4i which led to

• slightly less stress fibers (53 ± 3% vs 46 ± 7% for 4i vs control, respectively) and more filopodia-like deformations (57 ± 3% vs 33 ± 17% for 4i vs control, respectively) as compared to the control, result in increased wound healing ability in treated Sk-mel-2 cells. Molecular docking. To confirm the

Arene activation via π-bond localization: concepts and opportunities

• Paul Meiners,
• Julian J. Melder and
• Tobias Morack

Beilstein J. Org. Chem. 2026, 22, 257–273, doi:10.3762/bjoc.22.19

• dimension of control: chirality at the metal center. The resulting enantioenriched complexes have enabled a suite of asymmetric transformations (vide infra) [47]. Structure and properties To rationalize and predict the enhanced reactivity of η2-bound arenes, it is instructive to first examine the properties

• class of aromatic molecules, depending on the coordination site. When using arenes with the ability to tautomerize, additional latent functionality is introduced (Figure 7B). This dynamic binding behavior provides greater overall versatility, but precise control of the metal binding site is critical to

• Mo(I) species, followed by reduction in trifluorotoluene, afforded the enantioenriched trifluorotoluene complex with essentially complete retention at the metal stereocenter (er = 99:1). However, control of the metal stereocenter alone is insufficient: a defined interaction with the prochiral

Conformational analysis of difluoromethylornithine: factors influencing its gas-phase and bioactive conformations

• Matheus P. Freitas

Beilstein J. Org. Chem. 2026, 22, 237–243, doi:10.3762/bjoc.22.17

• complex. Elucidating this interplay is essential for rationalizing DFMO’s inhibitory potency and may also offer broader insight into how fluorinated substituents control molecular conformation in biologically relevant environments. Although the biological milieu is known to induce only minor structural

• together with Lewis-type effects control the orientation of the difluoromethyl group, are summarized in Table S1 (Supporting Information File 1). As expected, σCH → σ*CN is the dominant interaction (>3 kcal mol−1) and is present in all type-I structures. When these interactions are summed for each

Configuration–packing synergy enabling integrated crystalline-state RTP and amorphous-state TADF

• Ruiyan Wang and
• Yunan Wu

Beilstein J. Org. Chem. 2026, 22, 224–236, doi:10.3762/bjoc.22.16

• , lifetime, and efficiency, make them highly versatile for integration into advanced optoelectronic devices [9][10][11]. The performance limits of these devices, particularly in terms of their brightness, longevity, and efficiency, are largely dependent on the ability to precisely control the dynamics of the

• and exploring its potential applications in various optoelectronic devices. The ability to control and utilize both fluorescence and phosphorescence in 1 opens up promising avenues for future research, particularly in the development of advanced materials for light-emitting devices. At room