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

• demonstrated to be excellent chiral scaffolds in asymmetric synthesis, however, enantioselective synthesis of such planar-chiral complexes is still relatively undeveloped and remains as a challenging problem in asymmetric synthesis [24][25][26][27][28][29]. A new type of asymmetric olefin metathesis reaction

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

• %) [26][27]. In order to optimize the photophysical and physicochemical properties of norbornadiene (1a) with minimal impact on the energy density, scaffolds with multiple norbornadiene units have been investigated with the goal to accomplish higher energy storage density per molecule [20][21][22][29][30

Synthesis and uranyl(VI) extraction performance of a calix[4]pyrrole–tetrahydroxamic acid receptor

• Sara Karnib,
• Rana Baydoun,
• Wissam Zaidan,
• Nancy AlHaddad,
• Omar El Samad,
• Bilal Nsouli,
• Francine Cazier-Dennin and
• Pierre-Edouard Danjou

Beilstein J. Org. Chem. 2026, 22, 486–494, doi:10.3762/bjoc.22.36

• selective remediation strategies. Supramolecular materials, with their pre-organized structures, offer a promising route for uranium removal. Phenoxycalix[4]pyrroles (PCP) are well-known supramolecular scaffolds capable of selective metal binding, making them attractive candidates for designing uranium

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

• chiral scaffolds, which arise from hindered rotation between two planes connected by a single bond, have attracted increasing attention due to their widespread applications in chiral ligands, organocatalysts [1], and functional materials [2], making them highly valuable molecular frameworks in organic

• 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

• [41]. This strategy delivered excellent enantioselectivity, diastereoselectivity, and overall efficiency, underscoring its unique advantages in the synthesis of multiaxially chiral scaffolds. In parallel, Tanaka and co-workers advanced a [2 + 2 + 2] cycloaddition strategy to realize an asymmetric

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

• -mimicking scaffolds are a proven strategy in the design of anticancer drugs. Many cancer-related proteins (e.g., kinases, ATPases, DNA/RNA polymerases) have binding pockets designed for purine nucleotides (ATP, GTP). Oxazolopyrimidines can compete with purines or their analogues, inhibiting enzymatic

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

• Heterohelicenes are compelling chiral π-conjugated scaffolds for optoelectronic and chiral-photonic technologies because their helical frameworks and doped heteroatoms endow them with various photophysical, chiroptical, and electronic merits. However, unsymmetrical heterohelicenes remain rare, as their synthesis

• resulting plots show a clockwise diatropic current along the fused heterocycles and benzene rings, in agreement with the ring-current patterns reported for other helicene scaffolds [27] (Figure 2B). Enantiomerization barriers of oxaza[7]helicenes To investigate the enantiomerization (P/M) barriers of oxaza

• 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

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

• cyclohexene derivatives beyond sulfone and sulfonamide motifs. By combining ester enolate and amine addition sequences, this methodology was subsequently extended to the synthesis of architecturally complex polyheterocyclic frameworks (Scheme 3B) [62]. Such scaffolds are scarcely represented in contemporary

• complex, three-dimensional molecular scaffolds from simple arene feedstocks and underscoring the vast, still largely untapped potential for methodological innovation in this arena [95]. Activation of η4-coordinated arenes Among the less explored pathways in arene activation, η4-coordination of aromatic

• potential of this activation mode in catalysis. Conclusion and Future Directions Arenes remain privileged scaffolds in synthesis, recognized for their abundance and structural diversity. The deliberate perturbation of aromaticity through π-bond localization has emerged as a powerful strategy for molecular

A mild and atom-efficient four-component cascade strategy for the construction of biologically relevant 4-hydroxyquinolin-2(1H)-one derivatives

• Dmitrii A. Grishin,
• Kseniia I. Sharkovskaia,
• Ilya G. Kolmakov,
• Daria A. Ipatova,
• Rostislav A. Petrov,
• Nikolai D. Dagaev,
• Dmitry A. Skvortsov,
• Maria G. Khrenova,
• Valeriy V. Andreychev,
• Sergei A. Evteev,
• Yan A. Ivanenkov,
• Roman L. Antipin,
• Olga А. Dontsova and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2026, 22, 244–256, doi:10.3762/bjoc.22.18

• direct access to scarcely explored open-chain quinolinone esters, expanding the medicinal chemistry toolbox with promising scaffolds for drug discovery. Keywords: antibacterial activity; 4-hydroxyquinolin-2(1H)-one; ʟ-proline catalysis; Meldrum’s acid; Michael addition; multicomponent reaction

• attracted considerable attention due to their broad spectrum of biological activities (Figure 1) [19][20][21][22][23][24][25][26][27][28][29]. These include potent antibacterial, antiviral, antifungal, anti-inflammatory, and neurotropic effects, making them promising scaffolds for drug development [29][30

• -hydroxyquinoline scaffolds bearing both C6-halogen and γ-(3,4-dimethoxyphenyl)propanoic acid motifs. Existing approaches to such derivatives comprise typically multiple steps, are limited in scope, or require harsh reaction conditions, restricting their application in rapid analogue generation. The combination of

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

• promotes intersystem crossing (ISC) and spin–orbit coupling (SOC) for RTP and, when coupled with carbazole and other donor segments, facilitates the construction of twisted D–A scaffolds that reduce ΔEST, making them suitable for TADF [34][35][36]. On the one hand, the dual carbonyl groups provide an

Screwing the helical chirality through terminal peri-functionalization

• Devesh Chandra,
• Sachin and
• Upendra Sharma

Beilstein J. Org. Chem. 2026, 22, 205–212, doi:10.3762/bjoc.22.14

• surmounted, paving the way for the development of innovative approaches and new materials. Such advancements are expected to unlock the full potential of chiral helicenes. Representation of the general practices for the induction of helical chirality in organic scaffolds. A) Prelevant approach for the

• induction of helical chirality which majorly relies on the π extension of organic scaffolds via annulation/cycloaddition and B) central/axial to helical chirality conversion. C) Induction of helical chirality in [4]helicene via terminal peri-functionalization. D) Induction of helical chirality in [5

Streptoquinolines A and B, new antibacterial meroterpenoids produced by Streptomyces sp. TMPU-A0679

• Akiho Yagi,
• Hitomi Tomura,
• Ami Konno and
• Ryuji Uchida

Beilstein J. Org. Chem. 2026, 22, 185–191, doi:10.3762/bjoc.22.12

• Pathogens List (BPPL) in 2024, reaffirming VRE as a “High Priority Pathogen” for which research on and the development of new antimicrobial agents are urgently needed [4]. This emphasizes the continuing demand for antibiotics with novel chemical scaffolds and mechanisms of action. In our ongoing search for

• formed during extraction. The discovery of streptoquinolines expands the structural and biological diversities of drimane–quinoline-type meroterpenoids and provides novel insights into their potential as scaffolds for the development of antibacterial agents targeting multidrug-resistant Gram-positive

Circumventing Mukaiyama oxidation: selective S–O bond formation via sulfenamide–alcohol coupling

• Guoling Huang,
• Huarui Zhu,
• Shuting Zhou,
• Wanlin Zheng,
• Fangpeng Liang,
• Zhibo Zhao,
• Yifei Chen and
• Xunbo Lu

Beilstein J. Org. Chem. 2026, 22, 158–166, doi:10.3762/bjoc.22.9

• constructing S–C and S–N bonds, particularly in the synthesis of sulfilimines [19][20][21][22][23][24][25][26][27][28][29][30][31] and sulfinamidines [32][33][34]. Their tunable reactivity and modularity have positioned them as versatile scaffolds for sulfur–nitrogen architecture development. Our group

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

• access these saturated frameworks, catalytic hydrogenation of unsaturated arenes stands out as the most efficient one: it directly transforms planar sp2 systems into three-dimensional sp3-rich scaffolds via the shortest possible synthetic route, embodying both step economy and atom economy (Scheme 1) [25

• hydrogenation, they typically treat the topic from a purely methodological angle and seldom address its growing influence on retrosynthetic analysis [30][32][34][35][36]. Meanwhile, the capability to convert flat, readily accessible aromatic feedstocks into stereochemically defined, three-dimensional scaffolds

• sustained interest from synthetic chemists worldwide due to their pronounced antibacterial and anticancer properties. Since their discovery, bis-THIQ scaffolds have been constructed primarily through the Pictet–Spengler reaction, a cyclization strategy that continues to be widely employed in total synthesis

Synthesis and applications of alkenyl chlorides (vinyl chlorides): a review

• Daniel S. Müller

Beilstein J. Org. Chem. 2026, 22, 1–63, doi:10.3762/bjoc.22.1

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

• scaffolds for several synthetic or natural compounds [5]. Five-membered heterocycles include the thiazolidinone nucleus, characterized by two heteroatoms and a carbonyl group on the fourth carbon, as seen in compounds like rhodanine and thiazolidine-2,4-dione derivatives (Figure 1). These privileged

Visible-light-driven NHC and organophotoredox dual catalysis for the synthesis of carbonyl compounds

• Vasudevan Dhayalan

Beilstein J. Org. Chem. 2025, 21, 2584–2603, doi:10.3762/bjoc.21.200

• transformations. Previous reports displayed various research groups successfully designed and prepared a variety of triazolium-based NHCs, eventually leading to the development of chiral NHC scaffolds by Knight and Leeper [17], followed by the remarkable contributions of Bode [18], Rovis [19], Glorius [20

• production of ketone scaffolds, including drug moieties. The organocatalyzed acylation proceeds with excellent site selectivity and broad functional group tolerance of alkanes such as F, Cl, Br, I, CN, CF3, Me, and OMe. The reaction was achieved between acyl fluoride 4 and highly substituted alkane 7 in the

• existing metal-catalyzed C–H bond functionalization methods (Scheme 3) [53]. Recently, Scheidt et al. discovered an NHC/organic photoredox-catalyzed three-component coupling reaction for the efficient and novel preparation of γ-aryloxy ketone scaffolds 12. This transformation builds on the emerging field

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 precise than current treatments. Numerous multivalent constructs have been reported in literature, both as compounds with intrinsic anticancer activity [4] and nanocarriers for anticancer drug delivery [5][6]. In the development of multivalent compounds, macrocyclic scaffolds such as cyclodextrins

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

• was comparable to the selectivity of E and these scaffolds may present a lead for future nucleobase designs. The study further demonstrated a conflict between linker flexibility and triplex formation. However, the results point to the importance of entropy and related pre-organization of PNA bases for

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

• are ubiquitous and privileged heterocyclic scaffolds in various functional organic materials and naturally occurring products. Although extensive efforts have focused on developing synthetic strategies toward carbazole derivatives, direct regioselective functionalization of the carbazole core remains

• functionalization of carbazoles via C–H activation [48][49][50][51][52][53][54][55][56][57][58][59][60][61]. Among the variously substituted carbazole scaffolds, nitro-substituted carbazoles exhibit a diverse range of medicinal properties and serve as key starting materials for the synthesis of bioactive compounds

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

• scaffolds. From the standpoint of organic chemistry, it is evident that these compounds can be efficiently converted into a variety of versatile organic intermediates through the application of ring-opening reactions [49][50][51][52]. In addition to the aforementioned useful properties, the current methods

Recent advances in Norrish–Yang cyclization and dicarbonyl photoredox reactions for natural product synthesis

• Peng-Xi Luo,
• Jin-Xuan Yang,
• Shao-Min Fu and
• Bo Liu

Beilstein J. Org. Chem. 2025, 21, 2315–2333, doi:10.3762/bjoc.21.177

• reactivity modes and expand the structural diversity of accessible natural product scaffolds. Additionally, the highly reactive strained four-membered rings generated from these reactions present exciting opportunities for further functionalization. Studying their downstream transformations – particularly

Pathway economy in cyclization of 1,n-enynes

• Hezhen Han,
• Wenjie Mao,
• Bin Lin,
• Maosheng Cheng,
• Lu Yang and
• Yongxiang Liu

Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173

• synthetic intermediates, and used to successfully modify diverse bioactive scaffolds via late-stage functionalization, collectively demonstrating the method’s synthetic utility. In 2025, the Das group developed a palladium-catalyzed cycloisomerization of 2-alkynylbenzoate-cyclohexadienone that enables

• derivatives 31 (Scheme 7, path b). This work provided a novel approach for constructing substituted naphthalene and indene frameworks via gold-catalyzed cycloisomerization of 1,5-enynes. In 2016, Liu et al. achieved the stereoselective syntheses of furofuran and furopyran scaffolds from propargyl vinyl ethers

• heterocyclic scaffolds, which established a versatile platform for synthesizing structurally diverse indoline frameworks. Ligand-controlled cyclization of 1,n-enynes The core function of catalyst ligands lies in their ability to precisely modulate catalyst performance through electronic and steric effects. The

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

• heterocyclic scaffolds to obtain biologically interesting compounds (Scheme 1) [35][36][37][38][39][40][41]. The development of methods for the synthesis of triazole, tetrazole, piperazinone, and 1,4-benzodiazepine motifs are attractive from both synthetic and medicinal chemistry considerations [42][43][44][45

• scaffolds in a highly efficient manner. It was found that brominated azides do not undergo lactamization under the current conditions which presents an opportunity for further optimization of reaction conditions to expand the scope. Experimental General procedure for synthesis of analogs 7 and 8 A solution

• of compounds 6a (red) and 8a (blue). Ugi–azide reaction for the synthesis of 1,5-DS-T-containing heterocycles. Proposed Ugi–azide-initiated synthesis of polyheterocyclic scaffolds 7 and 8. 4-CR vs stepwise Ugi–azide reactions for the synthesis of 7a. Synthesis of benzodiazepines 7a–k. Reaction

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

Discovery of cytotoxic indolo[1,2-c]quinazoline derivatives through scaffold-based design

• Daniil V. Khabarov,
• Valeria A. Litvinova,
• Lyubov G. Dezhenkova,
• Dmitry N. Kaluzhny,
• Alexander S. Tikhomirov and
• Andrey E. Shchekotikhin

Beilstein J. Org. Chem. 2025, 21, 2062–2071, doi:10.3762/bjoc.21.161

• heterocyclic scaffolds are widely used in the treatment of various diseases, making them a common focus of research [1]. A substantial part of these compounds incorporate five- or six-membered nitrogen heterocycles. The indole and quinazoline cores represent two pharmacologically significant heterocyclic

• systems, exhibiting a wide range of biological activity, high level of druglikeness and broad opportunities for derivatizations, that make them privileged scaffolds in drug discovery [2][3]. The pharmaceutical significance of indole and quinazoline rings is evident by numerous FDA-approved drugs across

• structural fusion of indole and quinazoline pharmacophores offers exceptional opportunities for designing new therapeutic agents, combining the proven bioactivities of both privileged scaffolds. Chemical ways for the synthesis of indolo[1,2-c]quinazolines (Figure 1, top) are numerous and cover different