Synthesis and acaricidal activity against Varroa destructor of α- and γ-costic acid dimers

• Alessandro Santarsiere,
• Ernesto Santoro,
• Maria Letizia Ciavatta,
• Marianna Carbone,
• Sonia Ganassi,
• Cosimo Tedino,
• Antonio De Cristofaro,
• Antonio Evidente and
• Stefano Superchi

Beilstein J. Org. Chem. 2026, 22, 1088–1096, doi:10.3762/bjoc.22.87

• ][23][24]. In addition, the efficacy of both synthetic and natural acaricides, such as formic and oxalic acids [25], has declined due to the development of resistance in V. destructor populations [26]. Consequently, there is a growing interest in alternative, efficient, and environmentally friendly

Amino acid-based surfactants: sustainable synthesis and antimicrobial mechanisms

• Rafaela Gomes Bezerra,
• Lourdes Pérez and
• Francisco Fábio Oliveira de Sousa

Beilstein J. Org. Chem. 2026, 22, 1067–1085, doi:10.3762/bjoc.22.85

• increasingly ineffective over infections due to the gradual microbial resistance to conventional treatments. This aspect highlights the urgent need for the development of new antimicrobial agents. In this context, the amino acid-derived surfactants have proven to be a promising alternative to eradicate

• growth of bacteria, yeasts, and fungi has been demonstrated, offering an effective approach to prevent and combat the spread of infections, especially in the context of microbial resistance. Keywords: amino acids; antibiofilm; antimicrobial; biodegradable; surfactants; Introduction Traditional

• antimicrobial therapies are becoming progressively less effective against bacterial and fungal infections, primarily due to the escalating prevalence of antimicrobial resistance among the pathogens, particularly in Gram-positive bacteria (e.g., methicillin-resistant Staphylococcus aureus, vancomycin-resistant

Semisynthesis, characterisation, and antibacterial evaluation of a novel lecanoric acid-derived amide library

• Ethan D. Abbott,
• Sasha Hayes,
• Jonathan M. White,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2026, 22, 1023–1032, doi:10.3762/bjoc.22.81

• biofilm inhibition assay that used the Gram-negative pathogen, Pseudomonas aeruginosa [27]. P. aeruginosa is an opportunistic and drug resistant nosocomial pathogen, which is responsible for an increasing number of fatal infections in critically-ill individuals [28]. The pathogen’s increasing resistance

Electrochemical reduction of unsaturated carbon–carbon bonds via 3d transition-metal catalysis

• Geon Kang,
• Minki Jeon,
• Pooja Kumari Jat,
• Cheoljae Kim and
• Isaac Choi

Beilstein J. Org. Chem. 2026, 22, 955–981, doi:10.3762/bjoc.22.75

• spatially separated to prevent undesired interactions between reactive intermediates. Although such separation improves selectivity and mechanistic control, it may also introduce increased cell resistance and mass transport limitations. Consequently, the choice of cell configuration is closely tied to the

• configurations [75][76][77][78] have recently emerged as promising platforms for scalable electrochemical hydrogenation reactions. These advanced architectures offer enhanced mass transport, significantly reduced ohmic resistance, and the capability to operate at industrially relevant current densities, thereby

Site-specific labelling of native peptides and proteins: chemical and enzymatic strategies

• Antonio Angelastro,
• Jonathan Bargh,
• Subhajit Guria,
• Victor Laserna and
• Louis Luk

Beilstein J. Org. Chem. 2026, 22, 857–881, doi:10.3762/bjoc.22.67

• overcome resistance, highlighting the need for complementary site-specific antibody labelling strategies. Meanwhile, advances in high-throughput screening and AI-guided design have been creating new scaffolds, including nanobodies, de novo binders and peptoids, where tailored modification chemistries have

The trans-influence in gold chemistry from a catalytic perspective

• Manfred Bochmann

Beilstein J. Org. Chem. 2026, 22, 838–856, doi:10.3762/bjoc.22.66

• -elimination and chain walking make it necessary to invoke a hypothetical dicationic hydride intermediate, [(P^N)AuH(alkene)]2+. Based on the chemistry of the gold(III) hydrides described above, none of which showed any tendency for migratory alkene insertion [14], and in view of the resistance even of

Unsymmetrical sulfoxides with sterically hindered catechol fragment: synthesis, structure, electrochemical properties, and antiradical activity

• Daria A. Burmistrova,
• Vasiliy A. Fokin,
• Oleg P. Demidov,
• Mikhail A. Kiskin,
• Maxim V. Arsenyev,
• Andrey I. Poddel’sky,
• Nadezhda T. Berberova and
• Ivan V. Smolyaninov

Beilstein J. Org. Chem. 2026, 22, 828–837, doi:10.3762/bjoc.22.65

• , imparting resistance to various solvents [9][10]. Furthermore, catechol-containing compounds can serve as antioxidant biomimetic additives in lubricants [11]. One effective approach for the fine-tuning of polyphenol properties is functionalization via the introduction of heteroatoms (S, Se, Te) [12][13][14

Total synthesis of the capsular polysaccharide repeating unit towards the development of a glycoconjugate vaccine against Klebsiella pneumoniae ST512

• Shuo Zhang,
• Ondřej Daněk and
• Peter H. Seeberger

Beilstein J. Org. Chem. 2026, 22, 821–827, doi:10.3762/bjoc.22.64

• leading cause of nosocomial infections, characterized by high morbidity and an escalating degree of antimicrobial resistance [5][6][7][8]. This bacterium is frequently responsible for severe clinical conditions, including urinary tract infections, pneumonia, and septicemia [9][10]. The increasing

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

• analogous comparison using UV–vis absorption spectra along with a fatigue resistance verification. Representative thermal kinetic curves obtained by both UV–vis absorption and 1H NMR spectroscopy are shown in Figure 9. Thermal kinetics were optimized using the OPstat 6.10 software [33]. See Supporting

• contrasts the value found by UV–vis measurement (E/Z = 8:92). The fatigue resistance of compounds 1a–f (Figure 8B) was verified by ten consecutive 355/430 nm switching cycles revealing no structural degradation and photobleaching. Azobenzene monomers 1a–f were further incorporated into a thin polystyrene

• absorption spectra of azobenzene 1e corresponding to the dark-adapted PSS (black), 355 nm-adapted PSS (violet), and 430 nm-adapted PSS (blue) measured in DCE at c = 4 × 10−5 M (20 °C). B) Fatigue resistance of azobenzene 1e verified by ten consecutive 355/430 nm switching cycles. A) Thermal kinetics curve of

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

• of insulin resistance, inflammation, and hepatic steatosis [15]. The most advanced ASK1 inhibitor in clinical development is the compound celonsertib (Scheme 2). Following this, a series of new ASK1 inhibitors were derived using selonsertib as a lead compound in a variety of structure-optimized ways

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

• resistance [61]. Although many small-molecule inhibitors have also been developed for CDK9 so far, due to the high homology of the CDK family, inhibitors always tend to target a variety of CDK members, thereby reducing their specificity as therapeutic agents and chemical probes and results in many adverse

• proliferation [125]. Because long-term treatment with imatinib will lead to drug resistance in CML patients, the second generation of TKI was subsequently developed for treatment [129]. Although TKIs targeting BCR-ABL have achieved significant therapeutic effects, CML patients often need to take such drugs for

• : Serum-glucocorticoid-induced protein kinase (SGK) plays a key role in mediating resistance to phosphoinositide 3-kinase (PI3K)/Akt inhibition in breast cancer cells [132]. It has been reported that different ATP competitive inhibitors have similar affinity for all SGK isoforms [133][134]. Due to the

Towards the targeted protein degradation of CK2: design and synthesis of CAM4066-based PROTACs

• Sophie Day-Riley,
• Sona Krajcovicova,
• Aryaman Raj Sokhal,
• Jan L. Venne,
• Paul Brear,
• Marko Hyvönen,
• Benjamin C. Whitehurst,
• Jason S. Carroll and
• David R. Spring

Beilstein J. Org. Chem. 2026, 22, 611–619, doi:10.3762/bjoc.22.47

• . Despite successes with ATP-competitive inhibitors, small-molecule kinase inhibitors can be limited by reversible target engagement, off-target effects, and susceptibility to resistance mechanisms [7]. These challenges have motivated the exploration of alternative therapeutic modalities that move beyond

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

• strategies to combat the antibiotic resistance include, in particular, the synthesis of novel antibacterial agents based on isoxazole derivatives [17]. In this regards, the development of efficient and convenient methods for the sulfonyl-containing isoxazoles synthesis has received great attention. The most

Design and synthesis of an erdafitinib-based selective FGFR2 degrader

• Yumeng Jin,
• Shidong Wang,
• Sihan Pan,
• Shuqi Huang,
• Weichen Zhou,
• Xiaohao Huang,
• Lei Zheng and
• Lingfeng Chen

Beilstein J. Org. Chem. 2026, 22, 583–591, doi:10.3762/bjoc.22.44

• growth factor receptor 2 (FGFR2) to overcome the issues of drug resistance and adverse reactions associated with traditional inhibitors in the treatment of FGFR2-driven tumors. Erdafitinib was employed as the targeting ligand, and its aliphatic amine site was conjugated with a CRBN E3 ligase ligand to

• FGFR2-selective inhibitor, is the first highly selective FGFR2 inhibitor. Although substantial advancements have been made in developing FGFR2-targeted therapeutics, the sustained clinical efficacy of these inhibitors in oncology remains constrained by the emergence of acquired resistance mechanisms

• signaling pathway [35][36]. These advances have driven the development of several selective FGFR2 inhibitors, including erdafitinib, infiglatinib, and FGF401 [37][38][39]. However, issues such as acquired drug resistance and on-target toxicity emerging in clinical applications have limited the long-term

Modern synthetic pathways towards eribulin and its subunits

• Sebastian Dominik Graf

Beilstein J. Org. Chem. 2026, 22, 495–526, doi:10.3762/bjoc.22.37

• enhances its therapeutic efficacy but also helps in overcoming resistance mechanisms that limit the effectiveness of other microtubule-targeting agents. Research continues to explore additional applications of 1 in various cancer types, including non-small cell lung cancer, ovarian cancer, and other soft

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

• hydrolysis of phytic acid without phytases is extremely difficult because of its hydrolysis resistance, and only a few studies have considered the utilization of phytic acid as a phosphorus source [6]. In recent years, industrial applications of phytic acid have been investigated for its potential

Total synthesis of natural products based on hydrogenation of aromatic rings

• Haoxiang Wu and
• Xiangbing Qi

Beilstein J. Org. Chem. 2026, 22, 88–122, doi:10.3762/bjoc.22.4

• dehydrogenase type 1 (11-β-HSD-1), a key enzyme that alleviates insulin resistance by lowering cortisol production. Compound 157 emerged as a promising 11-β-HSD-1 inhibitor candidate. In 2016, researchers from Boehringer Ingelheim Pharmaceuticals and the University of Pennsylvania reported a concise and

Advances in Zr-mediated radical transformations and applications to total synthesis

• Hiroshige Ogawa and
• Hugh Nakamura

Beilstein J. Org. Chem. 2026, 22, 71–87, doi:10.3762/bjoc.22.3

• properties [1]. Among its notable physical attributes is its high corrosion resistance: metallic zirconium is exceptionally stable toward acids and bases at ambient temperature and is less susceptible to corrosion than titanium. Its low toxicity and excellent biocompatibility have historically supported 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

• biological agents has led to a rapid emergence of resistance, which in turn diminishes the national-wide and even global-wide food security. Moreover, toxins produced by fungi in diseased crops have serious impacts on animal and human health [2]. There remains high demand to develop new antifungal compounds

• action may not be consistent with those of known fungicide classes. This encouraging characteristic indicates its potential to overcome resistance to other fungicides [6][7][8]. Structurally, malayamycin A belongs to a class of modified nucleosides that mimic UDP (uridine 5′-diphosphate)-linked

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

• represents a promising approach to overcoming several limitations associated with traditional monovalent therapeutics, including drug resistance, off-target effects, high dosage requirements, and insufficient specificity. This strategy may pave the way for next-generation anticancer therapies more effective

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

• proximity to the fluorescent stopper. The reported findings involving dithienylethene-based rotaxanes prove their promising future in materials applications, mainly due to their high photofatigue resistance. Spiropyran While most spiropyran-based rotaxanes have the photoswitchable unit located on the axle

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

• sofosbuvir (2). Fluorination at C2 in the nucleoside results in metabolic stability and resistance to hydrolysis as it destabilizes the formation of a C1 oxocarbenium ion [5][6]. Trifluoromethylated γ-butyrolactones also find applications as antiviral agents, for example, lactone 4 which has activity against

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

• -designed Pd@S-1 and H-beta zeolite catalytic system, exhibiting high resistance to coking in presence of NH3. Subsequent carboxylation with CO2 and hydrogenation over Rh/C as catalyst led to racemic proline, an important precursor for pharmaceuticals, in quantitative yield. ᴅ-Proline was then obtained in

Solar thermal fuels: azobenzene as a cyclic photon–heat transduction platform

• Jie Yan,
• Shaodong Sun,
• Minghao Wang and
• Si Wu

Beilstein J. Org. Chem. 2025, 21, 2036–2047, doi:10.3762/bjoc.21.159

• [35][36][37][38][39][40][41]. Notably, the utilization of azobenzene-based materials in solar thermal storage applications is gaining considerable attention due to their advantages in low synthesis cost, facile molecular design, exceptional cycling stability, and superior fatigue resistance [6][8

• enables each azobenzene unit to store >200% more energy than isolated molecules, while achieving multi-order-of-magnitude improved storage lifetime and resistance to material degradation during repeated cycling. Feng and co-workers covalently grafted azobenzene groups onto RGO templates (Figure 3b) and

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

• forward and backward isomerisation can occur simultaneously. Moreover, some unwanted photochemical side reactions ΦS can occur, as shown in the Equation 4: A is one state of the photoswitch, B the second state, and B’ a generic degradation product. Fatigue resistance measures how many times the

• photoswitch can be switched before it is degraded by side reactions. It is typically reported as cyclability Z50, which “is the number of cycles required to reduce the initial absorbance at a specific wavelength by 50%” [3]. The quantum yield ΦS of these side reactions determines the resistance to fatigue of

• the E-chair isomer [51]. All the compounds show excellent resistance to fatigue. The behaviour of some (hetero)diazocines was also studied in water and solvent mixtures [50][51]. Interestingly, N-acetyl-diazocine possesses overall comparable properties and a longer thermal half-life, and it is also