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

• on the sulfoxide group. Keywords: antioxidant activity; catechol thioethers; redox-transformations; sulfoxides; X-ray analysis; Introduction Polyphenolic compounds can participate in redox processes and undergo a wide range of chemical modifications. As a result, they possess diverse biological

• activities and unusual physicochemical properties, which render them useful in various fields of chemistry. Catechol-containing compounds, in particular, are known for their antioxidant activity through the regulation of free-radical processes [1][2], and are used as antiparkinsonian [3][4][5], antitumor

Preparation of 3-(alkylamino)imidazo[1,2-a]pyridine-2-carbaldehydes via Kornblum oxidation and unexpected ring-opening reactions of the corresponding alcohols under oxidative conditions

• Sandile J. Mkhize,
• Memory Zimuwandeyi,
• Manuel A. Fernandes,
• Amanda L. Rousseau and
• Moira L. Bode

Beilstein J. Org. Chem. 2026, 22, 763–770, doi:10.3762/bjoc.22.58

• ; Kornblum oxidation; oxidative ring-opening; reductive amination; Introduction Imidazo[1,2-a]pyridines display a wide range of different biological activities, and this scaffold has come to be regarded as being biologically privileged [1]. Compounds containing the imidazo[1,2-a]pyridine core have been

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

• characterization of new brassinosteroid (BR) analogs, in which substituents with different electronegativities and molecular sizes have been attached to a C-22 benzoate function, are described. The biological activities of all new compounds were evaluated by using the rice lamina inclination test (RLIT) and

• range [1][2][3][4]. BRs play various important roles, such as, cell development, vascular differentiation, reproduction, modulation of gene expression [5][6], and other developmental processes [7][8]. Their natural occurrence and biological activities have been reviewed by different groups, and

• be possible to evaluate the contribution of different functions attached to ring A. Thus, herein the synthesis of analogs 17–22, starting from the precursor 16, is described. All compounds have been fully characterized by spectroscopic techniques (IR, 1D, 2D NMR and HRMS). The biological activities

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

• . longifolia and E. alternifolia as traditional medicines [6][7][8]. In recent times, Eremophila plants have been shown to generate impressive chemical diversity, along with a wide range of biological activities from both extracts or isolated natural products, such as antibacterial, antimalarial, and

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

• pyridine ring and carboxyl group [6][7][8][9]. On the other hand, the sulfonamide and sulfone groups are commonly found in the design of potential therapeutics with various types of biological activities, such as antimicrobial, antitubercular, antileishmanial, antiviral, anticancer, antidiabetic, anti

• mechanism of action of the active compounds, but these will be the subject of our further research. Examples of sulfonylisoxazoles with biological activities. The samples of isoxazole derivatives trigger SOS response in E. coli reporter strains. A) Agar plate coated with E. coli ΔtolC pDualrep2 (AmpR), B

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

• 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

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

• spectrum. Previously reported related meroterpenoids, such as thallusin and saccharoquinoline, exhibited no antibacterial biological activities – thallusin acts as an inducer of morphogenesis in some marine algae [7], whereas saccharoquinoline exhibits cytotoxicity towards the HCT-116 cancer cell line

Asymmetric Mannich reaction of aromatic imines with malonates in the presence of multifunctional catalysts

• Kadri Kriis,
• Harry Martõnov,
• Annette Miller,
• Mia Peterson,
• Ivar Järving and
• Tõnis Kanger

Beilstein J. Org. Chem. 2026, 22, 151–157, doi:10.3762/bjoc.22.8

• enolized carbonyl compound to an imine derived from an aldehyde or ketone and an amine, has been known for more than hundred years [1] and it has become an important method for creating C–C bonds [2][3][4]. The obtained Mannich bases exhibit a broad spectrum of biological activities [5][6] and have also

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

• strategy in total synthesis by Qi, 2023 and 2024 Indole-containing natural products have long attracted considerable interest in synthetic chemistry, owing to their pronounced biological activities and the biosynthetic relevance of indole as a key metabolite in diverse pathways. These biosynthetic

Recent advancements in the synthesis of Veratrum alkaloids

• Morwenna Mögel,
• David Berger and
• Philipp Heretsch

Beilstein J. Org. Chem. 2025, 21, 2657–2693, doi:10.3762/bjoc.21.206

• well as showcasing step- and redox-economy. This representation will be highly valuable for comparing the presented synthetic routes at the end of each subclass. Review Synthesis of Veratrum alkaloids The biological activities of the Veratrum alkaloids have been widely studied, but their synthesis

Chemoenzymatic synthesis of the cardenolide rhodexin A and its aglycone sarmentogenin

• Fuzhen Song,
• Mengmeng Zheng,
• Dongkai Wang,
• Xudong Qu and
• Qianghui Zhou

Beilstein J. Org. Chem. 2025, 21, 2637–2644, doi:10.3762/bjoc.21.204

• natural products. Representative CGs with promising biological activities. Retrosynthetic analysis of rhodexin A and sarmentogenin. Chemoenzymatic synthesis of sarmentogenin (2). Synthesis of rhodexin A. Optimization of the fermentation conditions of the biocatalytic C14–H α-hydroxylation. Supporting

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

• moieties exhibit a broad spectrum of biological activities [6][7][8]. They are found in several medicinal compounds (Figure 2), including etozoline (antihypertensive), ralitoline (anticonvulsant), thiazolidomycin (antibacterial), and in the type II diabetes mellitus drugs pioglitazone, epalrestat

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

• unique conformational constraints imposed by cyclization and diverse biological activities [1][2][3]. Specifically, plant-derived cyclopeptides represent a valuable source of potential lead compounds for drug discovery [4]. Segetalins A–H, J and K (1–10), isolated from the seeds of Vaccaria segetalis

• evaluation and structure–activity relationship studies. The systematic investigation of the their key biological activities, including estrogenic activity (assessed via breast cell proliferation assays), antitumor activity (evaluated through HeLa cell inhibition assays), and antibacterial activity (evaluated

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

• of cardiovascular diseases [21][22][23][24]. Additionally, compounds such as cinnzeylanol (6), cinncassiol B (7), and cinncassiol A (9) exhibit various potential biological activities, including insecticidal, ion channel modulatory, and immunosuppressive effects [25][26][27][28][29]. Review Synthetic

• research on Ryania diterpenoid natural products Ryania diterpenoids have garnered sustained interest in the synthetic chemistry community due to their complex, unique molecular structures and potential biological activities. This has motivated extensive research that has led to notable advances. This

• , structural elucidation, and biological activities. Particular emphasis has been placed on analyzing the strategic designs and key synthetic transformations employed in existing total syntheses, aiming to provide readers with a comprehensive overview of the current state of total synthesis achievements for

Catalytic enantioselective synthesis of selenium-containing atropisomers via C–Se bond formations

• Qi-Sen Gao,
• Zheng-Wei Wei and
• Zhi-Min Chen

Beilstein J. Org. Chem. 2025, 21, 2447–2455, doi:10.3762/bjoc.21.186

• selenides, recognized as valuable synthetic intermediates and biologically active compounds, have been demonstrated to exhibit a broad spectrum of biological activities. Among them, the synthesis of β-(selenium)vinyl sulfones can be accomplished via selenosulfonylation reactions initiated by free radicals

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

• , terpenoids, alkaloids, steroids and carbanucleosides. The spectrum of biological activities of the listed classes is wide and unique in efficacy. Natural prostaglandins are polyoxygenated derivatives of a hypothetical twenty-atom prostanoic acid, the C8–C12 atoms of which are contained in a cyclopentane ring

• contraction through aza-benzilic acid-type rearrangement (Scheme 13). Hasubanan-type alkaloids exhibit a wide range of biological activities, including antiviral, antimicrobial, and cytotoxic activities [46], while the biological activities and synthesis of structurally attractive norhasubanan-type alkaloids

• ], the mechanism and factors controlling the selectivity of the oxidative ring contraction in cyclic α-formyl ketones under the action of H2O2 were studied in detail. Due to their complex architecture and diverse biological activities, including antiviral, antitumor, antimalarial, and antifungal activity

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

• exhibit a wide range of biological activities [26][28][31][32][33][34][35]. The validity of the atom-efficient methodology under discussion has been demonstrated in experimental research; its efficacy in facilitating the rapid formation of multifunctional complex molecules being in contradistinction to

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

• bioactive molecules (Figure 1). This scaffold exhibits a broad range of pharmacological activities, including significant in vitro antimycobacterial properties [4], potent antitumor effects against melanoma cell lines [5], and antagonism of TH2 lymphocyte function [6]. Due to their wide-ranging biological

• activities, spiro[indoline-3,2'-pyrrolidines] have attracted substantial interest in medicinal chemistry, prompting the development of diverse synthetic strategies. Several methodologies have been reported for the synthesis of substituted spiro[indoline-3,2'-pyrrolidines] (Scheme 1), which can be broadly

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

• , characterized by a [5,6]-bisbenzannulated spiroketal moiety as its central structural motif. This key feature is critical to its potent biological activities, including strong inhibition of human telomerase [52], as well as its established roles as an effective antibiotic and HIV-1 reverse transcriptase

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

• exhibit diverse biological activities and have found application for the treatment of psychiatric disorders and neurodegenerative diseases [13][14][15][16][17]. Therefore, we now report our results in the synthesis and characterization of compounds 3 containing a 2,9-dihydro[1,2,3]thiadiazino[5,6-g]indole

Electrochemical cyclization of alkynes to construct five-membered nitrogen-heterocyclic rings

• Lifen Peng,
• Ting Wang,
• Zhiwen Yuan,
• Bin Li,
• Zilong Tang,
• Xirong Liu,
• Hui Li,
• Guofang Jiang,
• Chunling Zeng,
• Henry N. C. Wong and
• Xiao-Shui Peng

Beilstein J. Org. Chem. 2025, 21, 2173–2201, doi:10.3762/bjoc.21.166

• search tools and profiles applied. Review Construction of indoles Indoles, exhibiting interesting photoelectric properties and biological activities, were widely applied in organic synthesis, pharmacology and organic materials science [112][113][114][115][116][117][118][119][120][121][122][123][124][125

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

• prepared using this process. Antifungal activity assays against four general plant fungi demonstrated that several of the synthesized new furan products exhibited also broad and strong biological activities (Scheme 21) [95]. A metal-free efficient strategy was developed by the Gu group for the synthesis of

The application of desymmetric enantioselective reduction of cyclic 1,3-dicarbonyl compounds in the total synthesis of terpenoid and alkaloid natural products

• Dong-Xing Tan and
• Fu-She Han

Beilstein J. Org. Chem. 2025, 21, 2085–2102, doi:10.3762/bjoc.21.164

• complex natural products. On the other hand, terpenoids and alkaloids, with their intricate and diverse skeletal frameworks as well as the broad range of biological activities, have long been a major focus for synthetic chemists. Over the past fifteen years, significant progress has been made in the total

• : alkaloids; cyclic 1,3-dicarbonyl compounds; desymmetrization; enantioselective reduction; terpenoids; Introduction Terpenoids and alkaloids are two major classes of highly important natural products because they usually exhibit diverse and important biological activities, such as antitumor, anti

• -inflammatory, and antiarrhythmic effects etc., and show potential to be developed into drug candidates or novel medications for treating human diseases [1][2][3][4]. However, their scarcity in nature limits further research into their biological activities. Total synthesis is an important device to address the

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

• Street, Moscow 11991, Russia 10.3762/bjoc.21.161 Abstract Indolo[1,2-c]quinazoline derivatives have emerged as promising chemotype in drug discovery due to their versatile biological activities, including antimicrobial and antiviral properties. In this study, we report the design, synthesis, and

• [2,1-b]quinazoline-6,12-dione) and its derivatives are particularly noteworthy as they demonstrate multiple biological activities, including antibacterial, antitumor, antifungal, antiviral, anti-inflammatory, antileishmanial, antiplasmodial, etc. [18][19]. The structurally isomeric class – pyrimido

• as the activating agent under standard peptide coupling conditions. Cleavage of the Boc-protecting group with TFA afforded the target 6-oxoindolo[1,2-c]quinazoline-12-carboxamides 7a–c (Scheme 2). 3-Aminomethylindole derivatives represent a well-established class of compounds with diverse biological

Enantioselective desymmetrization strategy of prochiral 1,3-diols in natural product synthesis

• Lihua Wei,
• Rui Yang,
• Zhifeng Shi and
• Zhiqiang Ma

Beilstein J. Org. Chem. 2025, 21, 1932–1963, doi:10.3762/bjoc.21.151

• isolated from organisms are often asymmetric in their spatial structures, and these unique spatial structures are precisely what lead to their diverse biological activities [1][2][3][4]. For the synthesis of these natural products or bioactive molecules, chemists usually need to consider how to carry out

• adopted using compound 85 as the synthetic intermediate, which was prepared from diol 77 in a four-step sequence with 60% overall yield and 96% ee. In 2003, the Fukuyama group realized the first total synthesis of leustroducsin B, a microbial metabolite with various biological activities, featuring a