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

• via multiple C–C and C–O bonds, incorporating a labile hemiketal moiety. Furthermore, the presence of multiple oxygenated quaternary carbons classifies these molecules among the most highly oxidized diterpenoid natural products reported in the literature. In terms of biological activity, ryanodine (1

• channels has been extensively studied, the mechanisms of action of other ryanoid diterpenoid natural products remain poorly understood. Elucidating the structure–activity relationships (SAR) of these compounds is essential for identifying the functional groups critical for their biological activity

The intramolecular stabilizing effects of O-benzoyl substituents as a driving force of the acid-promoted pyranoside-into-furanoside rearrangement

• Alexey G. Gerbst,
• Sofya P. Nikogosova,
• Darya A. Rastrepaeva,
• Dmitry A. Argunov,
• Vadim B. Krylov and
• Nikolay E. Nifantiev

Beilstein J. Org. Chem. 2025, 21, 2456–2464, doi:10.3762/bjoc.21.187

• Galf-units is often important for the biological activity of these substances. Synthetic oligosaccharides structurally related to natural Galf-containing compounds are required for biochemical investigations and mapping active epitope fragments as well as the design of clinical diagnostics [12][13][14

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

• information. Keywords: biological activity; cyclopentane/enone; rearrangements; ring/cycle contractions; total synthesis; Introduction The functionalized cyclopentane/enone fragment is part of the structure of a large number of natural and synthetic biologically active compounds, including prostaglandins

• their high potential for biological activity, such as anti-inflammatory, antimicrobial, immunomodulatory, neuroprotective, hepatoprotective, hypoglycemic, hypolipidemic, antioxidant, antispasmodic, antitumoral, antiviral, and antiallergic. The breadth of the biological action of these cyclopentanoids is

• obtaining medically interesting dactylicapnosine-like analogues for detailed study of their biological activity. Matoba et al. [45] reported the first enantioselective synthesis of the hasubanane alkaloid (−)-metaphanine (70) and the norhasubanane alkaloid (+)-stephadiamine (71) using a cyclohexane ring

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

• -membered cyclic 1,3-dicarbonyl compounds Total synthesis of (+)-aplysiasecosterol A (+)-Aplysiasecosterol A (6) is a secosteroid that was isolated from the sea hare Aplysia kurodai by Kita and Kigoshi in 2015 [13]. Due to its natural scarcity, the biological activity has not been explored. In 2018, Li and

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

• 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

• for more extensive structure–activity relationship investigations. This work represents the first systematic evaluation of the anticancer potential of indolo[1,2-c]quinazoline derivatives, a chemotype previously studied mainly for synthetic accessibility but not for biological activity. Unlike prior

• ]. Given the presence of the indole moiety in indolo[1,2-c]quinazolin-6(5H)-one (1), the design of novel gramine-like analogues via aminomethyl substitution at position 12 is feasible. To evaluate the influence of the urea carbonyl group on biological activity, a modified scaffold, 6-methylindolo[1,2-c

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

• as low toxicity of these substances [42]. Biological activity screening also suggests that quinoxalinone-based compounds can inhibit aldose reductase [43], α-amylase and α-glucosidase [44], as well as key enzymes involved in the processes of saturated fatty acid conversion [45] and glycogenolysis [46

• 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

Understanding the origin of stereoselectivity in the photochemical denitrogenation of 2,3-diazabicyclo[2.2.1]heptene and its derivatives with non-adiabatic molecular dynamics

• Leticia A. Gomes and
• Steven A. Lopez

Beilstein J. Org. Chem. 2025, 21, 2007–2020, doi:10.3762/bjoc.21.156

• bicyclo[1.1.0]butane (a) and bicyclo[2.1.0]pentane (b). Molecules with biological activity are synthesized from bicyclo[1.1.0]butane (c) and bicyclo[2.1.0]pentane (d). Diastereoselectivity in the direct photolysis of 2,3-diazabicyclo[2.2.1]hept-2-enes. Mechanism for the photodenitrogenation of DBH

Aryl iodane-induced cascade arylation–1,2-silyl shift–heterocyclization of propargylsilanes under copper catalysis

• Rasma Kroņkalne,
• Rūdolfs Beļaunieks,
• Armands Sebris,
• Anatoly Mishnev and
• Māris Turks

Beilstein J. Org. Chem. 2025, 21, 1984–1994, doi:10.3762/bjoc.21.154

• it improves lipophilicity, oral absorption and biological activity [25]. Results and Discussion Arylation of aliphatic chain-containing propargylsilanes We started our investigation with the arylation of aliphatic chain-containing propargylsilanes. The starting material – tert-butyl(hept-1-yn-3-yl

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

• chemical literature regarding the biological activity (including anticancer properties) of phosphoric esters, reports on biological studies of systems based on the P=O fragment and oxirane skeletons are less common. Nevertheless, systems containing both of the mentioned structural motifs are rarely

• encountered in the literature. In this paper, we report the synthesis, biological activity, and electrochemical evaluation of glycidyl esters of phosphorus acids. Results and Discussion Synthesis of glycidyl esters of phosphorus acids 1–3 Glycidyl esters of phosphorus acids 1–3 were obtained by condensation

• 2.41–3.24 ppm and the POCH2- fragment at 3.66–4.36 ppm can be observed. The NMR data for the glycidyl esters of phosphorus acids 1–3 are comparable to those of related compounds. Biological activity of glycidyl esters of phosphorus acids To evaluate the biological activity of diastereomeric mixtures of

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

• replacing the azobenzene moiety of the already established partial agonist GluAzo with a diazocine unit. While both photochromic ligands show biological activity in the E form, the E-isomer is the thermodynamically more stable one for the azobenzene analog, whereas for the diazocine-modified

• neurotransmitter it is the Z form. Hence, GluAzo would permanently show biological activity in the dark (E-isomer), whereas the diazocine analog (Z-isomer) would be inert and only gets activated upon irradiation [58]. The Trauner group synthesised a puromycin diazocine 59 that shows higher affinity to the ribosome

Facile synthesis of hydantoin/1,2,4-oxadiazoline spiro-compounds via 1,3-dipolar cycloaddition of nitrile oxides to 5-iminohydantoins

• Juliana V. Petrova,
• Varvara T. Tkachenko,
• Victor A. Tafeenko,
• Anna S. Pestretsova,
• Vadim S. Pokrovsky,
• Maxim E. Kukushkin and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 1552–1560, doi:10.3762/bjoc.21.118

• another cycle via the single quaternary carbon atom C5 demonstrated significant biological activity, greater than analogs with non-spiro-bonded cyclic fragments [3][4]. Hydantoin derivatives also exhibit a wide range of biological activities. Compounds containing the hydantoin pharmacophore group, are

Ambident reactivity of enolizable 5-mercapto-1H-tetrazoles in trapping reactions with in situ-generated thiocarbonyl S-methanides derived from sterically crowded cycloaliphatic thioketones

• Grzegorz Mlostoń,
• Małgorzata Celeda,
• Marcin Palusiak,
• Heinz Heimgartner,
• Marta Denel-Bobrowska and
• Agnieszka B. Olejniczak

Beilstein J. Org. Chem. 2025, 21, 1508–1519, doi:10.3762/bjoc.21.113

• analysis of the isolated products of S–H and N–H insertion was carried out based on spectroscopic data (1H and 13C NMR) and the structures of two representatives were established by using the X-ray single crystal diffraction analysis method. Biological activity (cytotoxicity) of some selected products

• polymer chemistry [36] and the crop protection industry [37] as well. Therefore, in extension of a typically synthetic work, a preliminary study on biological activity of the hitherto unreported 1H-tetrazole derivatives such as thioaminals 9 and dithioacetals 10 was carried out and it demonstrated that

• . Supporting Information File 40: General information and experimental data of all isolated products, procedure for determination of biological activity, details of the crystal structure determination, and copies of 1H and 13C NMR spectra for all products. Acknowledgements The authors thank Prof. Zbigniew J

Heterologous biosynthesis of cotylenol and concise synthesis of fusicoccane diterpenoids

• Ye Yuan,
• Zhenhua Guan,
• Xue-Jie Zhang,
• Nanyu Yao,
• Wenling Yuan,
• Yonghui Zhang,
• Ying Ye and
• Zheng Xiang

Beilstein J. Org. Chem. 2025, 21, 1489–1495, doi:10.3762/bjoc.21.111

• with limited chemical transformations is highly desirable and should enable the discovery of new fusicoccane derivatives with improved biological activity. Inspired by the biosynthetic machinery of terpenoids, we have reported a hybrid synthetic strategy for accessing bioactive terpenoids by combining

Reactions of acryl thioamides with iminoiodinanes as a one-step synthesis of N-sulfonyl-2,3-dihydro-1,2-thiazoles

• Vladimir G. Ilkin,
• Pavel S. Silaichev,
• Valeriy O. Filimonov,
• Tetyana V. Beryozkina,
• Margarita D. Likhacheva,
• Pavel A. Slepukhin,
• Wim Dehaen and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2025, 21, 1397–1403, doi:10.3762/bjoc.21.104

• groups; synthesis; 1,2-thiazolines; thioamides; Introduction 1,2-Thiazoles (isothiazoles) exhibit a wide range of biological activity (Figure 1): antipoliovirus [1], anticancer [2][3][4][5][6][7], against Parkinson's disease [8], and diabetes [9][10][11], and are also used as microbiocides [12][13

Oxetanes: formation, reactivity and total syntheses of natural products

• Peter Gabko,
• Martin Kalník and
• Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

A multicomponent reaction-initiated synthesis of imidazopyridine-fused isoquinolinones

• Ashutosh Nath,
• John Mark Awad and
• Wei Zhang

Beilstein J. Org. Chem. 2025, 21, 1161–1169, doi:10.3762/bjoc.21.92

• group on the imidazopyridine moiety have direct electronic impact on the IMDA reaction. This integrated reaction process provided a new avenue for the preparation of heterocyclic scaffolds with potential biological activity. Experimental General procedure for the synthesis of intermediates 4 and 6 The

Acyclic cucurbit[n]uril bearing alkyl sulfate ionic groups

• Christian Akakpo,
• Peter Y. Zavalij and
• Lyle Isaacs

Beilstein J. Org. Chem. 2025, 21, 717–726, doi:10.3762/bjoc.21.55

• biomedical applications including as a solubilizing excipient for anticancer agents and as an in vivo sequestrant to reverse the biological activity of neuromuscular blocking agents, anesthetics, and drugs of abuse (e.g., methamphetamine and fentanyl) [54][55][56][57][58][59][60]. As a result of their

Origami with small molecules: exploiting the C–F bond as a conformational tool

• Patrick Ryan,
• Ramsha Iftikhar and
• Luke Hunter

Beilstein J. Org. Chem. 2025, 21, 680–716, doi:10.3762/bjoc.21.54

• , dramatic differences in biological activity are sometimes seen between the fluorinated stereoisomers (e.g., 111 and 112) [189]. This difference can be attributed to a conformational effect, whereby fluorine controls the pucker of the 5-membered ring through σC–H → σ*C–F hyperconjugation. Further examples

Semisynthetic derivatives of massarilactone D with cytotoxic and nematicidal activities

• Rémy B. Teponno,
• Sara R. Noumeur and
• Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 607–615, doi:10.3762/bjoc.21.48

• exhibit significant antimicrobial or cytotoxic activities upon testing [16]. This led us to hypothesize that possible chemical modification might enhance its biological activity. Therefore, the present research work aimed to investigate whether structural modifications could improve the biological

• groups, including an additional substitution on C-7, showed potent activity against nematodes. These acyl substituents, particularly the third cinnamoyl group on C-7, may significantly enhance the biological activity. This modification likely represents a key structural feature influencing its activity

• activity of this polyketide. Seven analogues of massarilactone D, compounds 2–8, were synthetized through acylation modifications aimed at enhancing the compound’s interactions with biological targets (Scheme 1). These acylated analogues were subsequently screened for their cytotoxicity against a panel of

Total synthesis of (±)-simonsol C using dearomatization as key reaction under acidic conditions

• Xiao-Yang Bi,
• Xiao-Shuai Yang,
• Shan-Shan Chen,
• Jia-Jun Sui,
• Zhao-Nan Cai,
• Yong-Ming Chuan and
• Hong-Bo Qin

Beilstein J. Org. Chem. 2025, 21, 601–606, doi:10.3762/bjoc.21.47

• , including insecticidal, antibacterial, anti-inflammatory, analgesic, and neurotrophic activities [3]. In 2013, Wang’s group isolated (±)-simonsol C from star anise, which features a unique 6/5/6 tricyclic benzofuran structure [4]. They found that it exhibits biological activity that promotes neuronal

Formaldehyde surrogates in multicomponent reactions

• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Bernhard Westermann

Beilstein J. Org. Chem. 2025, 21, 564–595, doi:10.3762/bjoc.21.45

• and within shorter reaction times (Scheme 36). In recent years, several groups have applied these strategies to identify products with biological activity [94][95]. Representative examples are shown in Scheme 37. On the other hand, the van Leusen three-component reaction of an aryl-substituted tosyl

Study of the interaction of 2H-furo[3,2-b]pyran-2-ones with nitrogen-containing nucleophiles

• Constantine V. Milyutin,
• Andrey N. Komogortsev and
• Boris V. Lichitsky

Beilstein J. Org. Chem. 2025, 21, 556–563, doi:10.3762/bjoc.21.44

• biological activity [1][2][3]. Among the numerous approaches using considered furanones as starting compounds the recyclization processes are of significant interest [4][5]. The important subclass of such synthetic methods is the interaction with nitrogen-containing reagents. In this case depending on the

• and allomaltol derivatives have the wide variety of biological activity [12][13][14][15][16]. This means that designing such hybrid products can significantly alter the pharmacological properties. Results and Discussion The starting compounds 1 were prepared from allomaltol employing a previously

Synthesis, characterization, antimicrobial, cytotoxic and carbonic anhydrase inhibition activities of multifunctional pyrazolo-1,2-benzothiazine acetamides

• Ayesha Saeed,
• Shahana Ehsan,
• Muhammad Zia-ur-Rehman,
• Erin M. Marshall,
• Sandra Loesgen,
• Abdus Saleem,
• Simone Giovannuzzi and
• Claudiu T. Supuran

Beilstein J. Org. Chem. 2025, 21, 348–357, doi:10.3762/bjoc.21.25

• evolves [3]. Complex chemical scaffolds with more than one protein-engaging functionality in a single molecule are advantageous for selectivity. This concept of synergistic compounds and complex chemical interactions helps to boost biological activity and prolongs the emergence of resistance in pathogens

Red light excitation: illuminating photocatalysis in a new spectrum

• Lucas Fortier,
• Corentin Lefebvre and
• Norbert Hoffmann

Beilstein J. Org. Chem. 2025, 21, 296–326, doi:10.3762/bjoc.21.22

• of the biological activity and to find biomedical applications, different releasing systems of this anion are developed. The peroxynitrite anion is formed by coupling of nitric oxide (NO) and the superoxide (O2•−). An efficient system has been developed to realize this reaction (Scheme 16) [74]. In a

Visible-light-promoted radical cyclisation of unactivated alkenes in benzimidazoles: synthesis of difluoromethyl- and aryldifluoromethyl-substituted polycyclic imidazoles

• Yujun Pang,
• Jinglan Yan,
• Nawaf Al-Maharik,
• Qian Zhang,
• Zeguo Fang and
• Dong Li

Beilstein J. Org. Chem. 2025, 21, 234–241, doi:10.3762/bjoc.21.15

• as a vital pharmacophore in medicinal chemistry due to its special biological activity [11][12][13]. In particular, the tricyclic benzimidazole skeleton is ubiquitous in many bioactive compounds and therapeutic agents (Figure 1b) [14][15][16]. Recent studies have shown that fluorinated benzimidazole