Light-enabled intramolecular [2 + 2] cycloaddition via photoactivation of simple alkenylboronic esters

• Lewis McGhie,
• Hannah M. Kortman,
• Jenna Rumpf,
• Peter H. Seeberger and
• John J. Molloy

Beilstein J. Org. Chem. 2025, 21, 854–863, doi:10.3762/bjoc.21.69

• considering recent advances enabling subsequent intramolecular H-atom abstraction [51] and efficient rearrangements [73][74]. A) Energy transfer catalysis of alkenes in organic synthesis. B) Energy transfer catalysis of conjugated borylated alkenes. C) Energy transfer catalysis of simple alkenylboronic esters

• . Probing boron effects on reactivity (A) and confirming the generation of a photostationary state equilibrium (B). Standard reaction conditions: (E)-1 (0.1 mmol), xanthone (5 mol %), MeCN (0.03 M), rt, 16 h. Probing EnT catalysis enabled [2 + 2] cycloaddition of simple alkenylboronic esters. Establishing

• cyclobutyldiol. A) Product derivatization and B) transition-metal EnT catalysis. Reaction conditions A): 4d (1 equiv), H2O2 (30 wt % in H2O), aq NaH2PO4, THF, 0 °C; B) 4 (1 equiv), KF (4 equiv), ʟ-tartaric acid (2.1 equiv), MeOH, MeCN, H2O, rt. Probing EnT catalysis of alkenylboronic ester 1a via alkene

Unraveling cooperative interactions between complexed ions in dual-host strategy for cesium salt separation

• Zhihua Liu,
• Ya-Zhi Chen,
• Ji Wang,
• Qingling Nie,
• Wei Zhao and
• Biao Wu

Beilstein J. Org. Chem. 2025, 21, 845–853, doi:10.3762/bjoc.21.68

• of the dual-host strategy for ion pair extraction via solid–liquid method, showing the cooperative interaction between complexed anion and complexed cation. (b) Molecular structures of 18-crown-6 (for Cs+ binding) and tripodal hexaurea receptor L (for anion binding), where cooperative interactions of

• for clarity. Stacked 1H NMR spectra of (a) free anion receptor L and its complexes with one equivalent of (b) Cs2SO4, (c) Cs2CO3, and (d) Cs3PO4 in the presence of 18-crown-6 (DMSO-d6, 1 mM, 400 MHz, 298 K). Single crystal structure of complexed Cs2CO3 (CCDC: 2411574) with 18-crown-6 and tripodal

• Cs+ is stabilized by six ion-dipole interactions from carbonyl (O=C) and nitro (-NO2) groups. The overall stoichiometry of Cs+, CO32−, 18-crown-6 and anion receptor is 2:1:1:1. Nonpolar hydrogen atoms and solvent molecules are omitted for clarity. (b) Stacked 1H NMR spectra of free anion receptor L

Chitosan-supported CuI-catalyzed cascade reaction of 2-halobenzoic acids and amidines for the synthesis of quinazolinones

• Xuhong Zhao,
• Weishuang Li,
• Mengli Yang,
• Bojie Li,
• Yaoyao Zhang,
• Lizhen Huang and
• Lei Zhu

Beilstein J. Org. Chem. 2025, 21, 839–844, doi:10.3762/bjoc.21.67

• (0.2 mmol), amidine hydrochloride 2 (0.3 mmol, 1.5 equiv), CS@CuI (5.0 mol %), Na2CO3 (1.25 mmol, 2.5 equiv), iPrOH/H2O 9:1 (2.0 mL), 90 °C, 12 h, argon atmosphere. Proposed mechanism for the CS@CuI-catalyzed synthesis of quinazolinones. Scaling-up experiment (a) and recyclability of CS@CuI (b

Substituent effects in N-acetylated phenylazopyrazole photoswitches

• Radek Tovtik,
• Dennis Marzin,
• Pia Weigel,
• Stefano Crespi and
• Nadja A. Simeth

Beilstein J. Org. Chem. 2025, 21, 830–838, doi:10.3762/bjoc.21.66

• -PAP-CN upon 365 nm irradiation (12.5 µM in CH3CN, at 25 °C). B) Absorbance of the same sample at 365 nm (Ar, 365nm) after reaching PSS365 or PSS455, respectively, to show the recyclability. Hammett plot of NAc-PAP derivatives. Eyring plots for NAc-PAP-CN and NAc-PAP-OMe. Reaction pathway for

• synthesizing NH-substituted, methylated-, and acetylated arylazopyrazoles. Conditions: A) NaNO2, AcOH + HCl at 0 °C, then, 2,4-pentanedione, NaOAc in EtOH + H2O, reflux; B) MeNHNH2, EtOH, reflux; C) NH2NH2, EtOH, reflux; D) AcCl, NaOAc in DCM, 0 °C to rt. Photophysical properties of synthesized PAP derivatives

4-(1-Methylamino)ethylidene-1,5-disubstituted pyrrolidine-2,3-diones: synthesis, anti-inflammatory effect and in silico approaches

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Luc Van Meervelt,
• Do Thi Thao and
• Nguyen Minh Thong

Beilstein J. Org. Chem. 2025, 21, 817–829, doi:10.3762/bjoc.21.65

• Nguyen Tran Nguyen Vo Viet Dai Luc Van Meervelt Do Thi Thao Nguyen Minh Thong The University of Danang-University of Science and Education, Danang 550000, Vietnam Biomolecular Architecture, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium Institute of Biotechnology

• further purification. For column chromatography, 70–230 mesh silica 60 (E. M. Merck) was used as the stationary phase. Electrospray ionization–high-resolution mass spectra (ESI–HRMS) were acquired on a SCIEX X500 QTOF instrument in the positive ion mode. A Büchi melting point B-545 apparatus was used to

Synthesis and photoinduced switching properties of C₇-heteroatom containing push–pull norbornadiene derivatives

• Daniel Krappmann and
• Andreas Hirsch

Beilstein J. Org. Chem. 2025, 21, 807–816, doi:10.3762/bjoc.21.64

• result in NBD or in another rearranged species. Conversion of O-NBD1 to O-QC1 using a 275 nm LED. The UV–vis spectrum was recorded in MeCN; b) the respective NMR spectrum was recorded in CDCl3; c) similar UV–vis experiment for N-NBD1 measured in MeCN; d) conversion of N-NBD to an unidentified photoisomer

Regioselective formal hydrocyanation of allenes: synthesis of β,γ-unsaturated nitriles with α-all-carbon quaternary centers

• Seeun Lim,
• Teresa Kim and
• Yunmi Lee

Beilstein J. Org. Chem. 2025, 21, 800–806, doi:10.3762/bjoc.21.63

• hydride complex A through the reaction of IPrCuCl with DIBAL-H [35]. Copper hydride species A reacts regioselectively with allene 1 to form the allylcopper intermediate B. Subsequent transmetalation between allyl-Cu B and DIBAL-H generates allylaluminum species C and regenerates IPrCuH (A). The final step

Development and mechanistic studies of calcium–BINOL phosphate-catalyzed hydrocyanation of hydrazones

• Carola Tortora,
• Christian A. Fischer,
• Sascha Kohlbauer,
• Alexandru Zamfir,
• Gerd M. Ballmann,
• Jürgen Pahl,
• Sjoerd Harder and
• Svetlana B. Tsogoeva

Beilstein J. Org. Chem. 2025, 21, 755–765, doi:10.3762/bjoc.21.59

• Carola Tortora Christian A. Fischer Sascha Kohlbauer Alexandru Zamfir Gerd M. Ballmann Jurgen Pahl Sjoerd Harder Svetlana B. Tsogoeva Department of Chemistry and Pharmacy, Organic Chemistry Chair I and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität

• –O5 2.3438(13), P–O4 1.4793(13), P–O1 1.4914(13), O4–Ca-O4′ 99.09(7)°. (A) Proposed catalytic cycle for the hydrocyanation of hydrazones with the Ca–BINOL phosphate catalyst. (B) Catalytic cycle for asymmetric hydrocyanation of a Z-hydrazone, giving the "S" product, catalyzed by a Ca–BINOL phosphate

Orthogonal photoswitching of heterobivalent azobenzene glycoclusters: the effect of glycoligand orientation in bacterial adhesion

• Leon M. Friedrich and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2025, 21, 736–748, doi:10.3762/bjoc.21.57

• well as of 3, 4, and 5 is illustrated by the respective switching cycles in Figure 2A and B. In a next step, thermal relaxation of the metastable ZZ and Z isomers, respectively, was studied. In 2, thermal relaxation of the ZZ isomer can occur via the EZ or the ZE isomer (Figure 2C), respectively [24

• . These differences correspond to the structures of the various ligand–FimH complexes (Figure 4A and B), however, it is difficult to substantiate the measured binding differences in detail. For example, it is not apparent that secondary interactions performed by the scaffold mannoside portion in the

• various PSS are clearly predominated by one isomer (cf. Table 1 and Figure 2A and B), the measured inhibitory potential can be indeed correlated to the impact of glycan conformation within certain boarders of accuracy. In conclusion, the isomeric state of the azo group in photoswitchable azobenzene

Synthesis of HBC fluorophores with an electrophilic handle for covalent attachment to Pepper RNA

• Raphael Bereiter and
• Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 727–735, doi:10.3762/bjoc.21.56

• Na2SO4 and concentrated to dryness. Finally, the crude compound was purified via silica gel chromatography using 50–70% ethyl acetate in cyclohexane as gradient. General procedure B. The product obtained in general procedure A was dissolved in ethanol mixed with 4-cyanophenylacetonitrile and 8 drops of

• obtained in general procedure B was dissolved in dichloromethane and cooled to 0 °C under argon atmosphere. Then, triphenylphosphine and carbon tetrabromide were added and stirred at room temperature for two hours. Afterwards, the entire mixture was loaded on a silica gel column and eluted with 100

• % dichloromethane. General procedure D. In a manner similar to [11], the product obtained in general procedure B, methanesulfonyl chloride, and triethylamine were dissolved in dichloromethane and stirred overnight at room temperature. After reaction control and 100% consumption of the starting material, the entire

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

• closer to the ureidyl C=O portals [68][69]. However, a close examination of the structures of M0 and M1 show that the ionic group for M1 is a sulfonate and for M0 is a sulfate. Accordingly, M1 and M0 differ in two ways: a) different (CH2)n linker length and b) different ionic group (sulfonate versus

• observe two resonances for the C=O groups, three resonances for the aromatic C-atoms, two methyl resonances, three resonances for the bridging CH2 groups, and five of the six resonances for the sidearm (b and c) and equatorial glycoluril C-atoms. The negative-ion electrospray ionization mass spectrum

• , 71.2, 69.5, 67.4, 52.5, 48.4, 35.0, 16.3, 15.4 ppm; ESIMS (m/z): 751.13 ([M − 2Na]2−), calcd for [C50H56N16Na2S4O28]2−, 751.1064. Chemical structures of CB[n] and selected acyclic CB[n]-type molecular containers M1 and M0. a) 1H NMR spectrum (600, D2O, rt) and b) 13C NMR spectrum recorded (150 MHz, D2O

Photochemically assisted synthesis of phenacenes fluorinated at the terminal benzene rings and their electronic spectra

• Yuuki Ishii,
• Minoru Yamaji,
• Fumito Tani,
• Kenta Goto,
• Yoshihiro Kubozono and
• Hideki Okamoto

Beilstein J. Org. Chem. 2025, 21, 670–679, doi:10.3762/bjoc.21.53

• the manipulation of the solid-state optoelectronic nature of polycyclic aromatic molecules to develop future functional materials in organic electronics. Chemical structures of phenacenes studied in this work. UV–vis and fluorescence spectra of F8PIC (a), F8FUL (b), and F87PHEN (c) (red lines) and the

• corresponding parent phenacenes (black lines) in CHCl3. The broken lines show long-wavelength absorption bands at 10-times magnification of the intensity for clarity. Photoluminescence spectra of F8PIC (a), F8FUL (b), and F87PHEN (c) in toluene at 77 K. Electronic spectra of F8PIC (a), F8FUL (b), and F87PHEN (c

• ) (red lines) and the corresponding parent phenacenes (black lines) in the solid state. (a) The MO diagrams of the parent and fluorinated phenacenes (B3LYP/6-31+G(d,p)). H and L, respectively, denote HOMO and LUMO; (b) electrostatic potentials mapped on the total S0 electron density surface in the ground

Asymmetric synthesis of fluorinated derivatives of aromatic and γ-branched amino acids via a chiral Ni(II) complex

• Maurizio Iannuzzi,
• Thomas Hohmann,
• Michael Dyrks,
• Kilian Haoues,
• Katarzyna Salamon-Krokosz and
• Beate Koksch

Beilstein J. Org. Chem. 2025, 21, 659–669, doi:10.3762/bjoc.21.52

• ) was carried out on aluminum plates coated with silica gel 60 F254 (Merck, Darmstadt, Germany). The TLC plates were analyzed using UV light at 254 nm. Flash chromatography was performed on silica gel 60 M from Macherey-Nagel (grain size of 40−63 μm). The conditions are given in the form “(A/B = a:b

• )”, where A/B refers to the solvents used as mobile phase and a:b to their volume ratio. Analytical high-performance liquid chromatography (HPLC) was used to determine the purity of the obtained Fmoc-protected amino acids. The respective HPLC runs were carried out on a Primaide DAD system (VWR/Hitachi

• different fluorinated amino acids and target fluorinated amino acids described in the context of this work. Synthesis of fluorinated aromatic amino acids 2 and 3. a) Gram-scale synthesis of fluorinated alkyl iodide precursor 10; b) Synthesis of trifluorinated leucine analogs 12a and 12b. Optimization of the

Recent advances in allylation of chiral secondary alkylcopper species

• Minjae Kim,
• Gwanggyun Kim,
• Doyoon Kim,
• Jun Hee Lee and
• Seung Hwan Cho

Beilstein J. Org. Chem. 2025, 21, 639–658, doi:10.3762/bjoc.21.51

• complex's chemical behavior (Scheme 6). Among the analyzed four-coordinate boron species, the unreactive trialkoxyborate complex A exhibited the most compact B–C bond at 1.621 Å. Following a clear trend, the B–C bond distance progressively lengthened as oxygen atoms were substituted with elements of lower

• electronegativity, reaching 1.648 Å in the reactive alkoxytrialkyl complex D and 1.659 Å in the tetraalkyl "ate" complex E. The B–C bond lengths in amido- and alkyl-substituted boronic ester complexes B and C fell between these extremes, suggesting an intermediate level of activation. These findings prompted

• transfer, X-ray crystallographic analysis of the (tert-butyl)(adamantyl)Bpin·Li(THF)2 complex revealed that the B–(adamantyl) bond is shorter than the B–(tert-butyl) bond (1.673 vs 1.692 Å). DFT calculations further illuminated the underlying mechanism by comparing two distinct transition states: TS1

Entry to 2-aminoprolines via electrochemical decarboxylative amidation of N‑acetylamino malonic acid monoesters

• Olesja Koleda,
• Janis Sadauskis,
• Darja Antonenko,
• Edvards Janis Treijs,
• Raivis Davis Steberis and
• Edgars Suna

Beilstein J. Org. Chem. 2025, 21, 630–638, doi:10.3762/bjoc.21.50

• mM concentration, respectively, in 5:1 MeCN/H2O (0.1 M Et4N–BF4). B) Anodic oxidation of pyrrolidine 6a. Plausible mechanism for formation of pyrrolidine 6a and hemiaminal 10a. Preparation of malonic acid monoester 9a. Electrolysis of acid 9d in deuterated solvents. Scope of the decarboxylative

Photocatalyzed elaboration of antibody-based bioconjugates

• Marine Le Stum,
• Eugénie Romero and
• Gary A. Molander

Beilstein J. Org. Chem. 2025, 21, 616–629, doi:10.3762/bjoc.21.49

• ; ALFRED PASIEKA/SCIENCE PHOTO LIBRARY, No. 585105259. This content is not subject to CC BY 4.0. a. Photoredox catalytic cycles; b. absorption spectrum of photosensitizers. Therapeutic window indicates the most appropriate wavelength range to apply irradiation for biological applications. Graph

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

• Remy B. Teponno Sara R. Noumeur Marc Stadler Department Microbial Drugs, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany and Institute of Microbiology, Technische Universität Braunschweig, Spielmannstraße 7, 38106 Braunschweig, Germany Department of Chemistry

• curvupallides, and the spirostaphylotrichins [8][9][10]. Massarilactones A and B were isolated for the first time from the freshwater aquatic fungus Massarina tunicata [8], massarilactones C and D from Coniothyrium sp. associated to the succulent plant Carpobrotus edulis [11], massarilactones E, F, and G from

• [14]. Massarilactones A and B were earlier shown to exhibit antimicrobial activity against Bacillus subtilis (ATCC 6051) and Staphylococcus aureus (ATCC 29213), affording zones of inhibition varying from 12 to 19 mm at 200 μg/disk [8], while massarilactone H displayed moderate cytotoxicity against

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

• conversion of DMSO to MMS, a wide range of 4-arylquinolines can be synthesized (Scheme 8, path I) [24]. In this reaction, the persulfate ion generates the thionium ion (MMS), which is trapped by a nucleophilic aniline. The loss of methyl sulfide generates an imine intermediate B, which, in turn, reacts with

• ). Additionally, the Tiwari group developed a metal-free protocol using only K2S2O8 as an oxidant for the activation of DMSO to MMS (Scheme 8, path II) [38]. Under these conditions, an alternative mechanism arises in which the imine intermediate B, formed as previously stated through reaction between the aniline

• the same amine component) deprotonates the terminal alkyne, generating the metal acetylide derivative A, which is the active nucleophilic species in the reaction. Intermediate A undergoes an oxidative addition by the dihaloalkane, generating intermediate B. This undergoes reductive elimination to

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

• Constantine V. Milyutin Andrey N. Komogortsev Boris V. Lichitsky N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Pr., 47, Moscow, 119991, Russian Federation 10.3762/bjoc.21.44 Abstract For the first time, the reaction of substituted 2H-furo[3,2-b]pyran-2-ones

• with diverse N-nucleophiles was investigated. It was shown that the direction of the process depends on the type of employed nitrogen-containing reagent. For example, condensation with aliphatic amines leads to 2H-furo[3,2-b]pyran-2,7(3H)-diones bearing an exocyclic enamine moiety. At the same time

• unambiguously confirmed by X-ray diffraction. Keywords: allomaltol; enamines; 2H-furo[3,2-b]pyran-2-ones; pyrazol-3-ones; recyclization; Introduction Substituted furan-2(5H)-ones (butenolides) are widely used as precursors for the preparation of diverse types of heterocyclic compounds possessing various

Vinylogous functionalization of 4-alkylidene-5-aminopyrazoles with methyl trifluoropyruvates

• Judit Hostalet-Romero,
• Laura Carceller-Ferrer,
• Gonzalo Blay,
• Amparo Sanz-Marco,
• José R. Pedro and
• Carlos Vila

Beilstein J. Org. Chem. 2025, 21, 533–540, doi:10.3762/bjoc.21.41

• yield decreased, possibly due to the formation of imine B, which might be favored by the dehydration effect of the molecular sieves. Conclusion In summary, a regioselective and diastereoselective vinylogous addition reaction of 4-alkenyl-5-aminopyrazoles to alkyl trifluoropyruvate has been studied

• trifluoropyruvates. Synthesis of the starting materials 3. Scope of the reaction. Reaction conditions A: 3 (0.2 mmol) and 4 (0.6 mmol) in 2 mL of toluene at 70 °C. Reaction conditions B: 3 (0.2 mmol), 4 (0.6 mmol), and SQ-1 (10 mol %) in 2 mL of toluene at 50 °C. Yields refer to isolated yields after column

Cryptophycin unit B analogues

• Thomas Schachtsiek,
• Jona Voss,
• Maren Hamsen,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2025, 21, 526–532, doi:10.3762/bjoc.21.40

• derivatives lack a covalent attachment handle. By making use of drug conjugates, toxic payloads such as cryptophycins can be selectively delivered to the target site. We present the synthesis of two conjugable cryptophycins with amino groups in unit B, representing potential payloads for drug conjugates

• conjugable payloads by our group. Modifications of unit B with conjugation handles are scarcely explored and mainly include the exchange of the para-methoxy group (Figure 1B). The sole exchange of the para-methoxy group of cryptophycin-52 (IC50 = 22 pM) by a hydroxy group reduces the cytotoxicity by

• of N-alkylation on the non-chlorinated unit B derivatives. Results and Discussion For the synthesis of unit B derivatives with amino groups instead of the naturally occurring methoxy group ᴅ-phenylalanine served as the fundamental substrate (Scheme 1). Nitration [23] followed by methyl ester

Deep-blue emitting 9,10-bis(perfluorobenzyl)anthracene

• Long K. San,
• Sebastian Balser,
• Brian J. Reeves,
• Tyler T. Clikeman,
• Yu-Sheng Chen,
• Steven H. Strauss and
• Olga V. Boltalina

Beilstein J. Org. Chem. 2025, 21, 515–525, doi:10.3762/bjoc.21.39

• between the ANTH cores. The ANTH hexagons that appear to be overlapped (see Figure 2, bottom left) are separated by 4.154 Å and are tilted from each other by 21.6°. The columns of ANTH cores are insulated along the crystallographic b-axis by the BnF groups, which can be more clearly seen by viewing down

• -10-bis(perfluorobenzyl)anthracene were mounted in a paratone oil on glass fiber rods glued to a small copper wire. X-ray diffraction data were collected at ChemMatCARS (CARS = consortium for advanced radiation sources) sector 15-B at the Advanced Photon Source (Argonne National Laboratory). The data

• software (APEX II) was employed [38], and Bruker SHELXTL software [39] was used for structure solution, refinement, and graphics. Crystal data for 9,10-ANTH(BnF)2: C28H8F14, M = 610.34, orthorhombic, a = 11.5338(4) Å, b = 24.6701(9) Å, c = 8.0275(3) Å, α = 90°, β = 90°, γ = 90°, V = 2284.15 Å3, T = 100(2

Unprecedented visible light-initiated topochemical [2 + 2] cycloaddition in a functionalized bimane dye

• Metodej Dvoracek,
• Brendan Twamley,
• Mathias O. Senge and
• Mikhail A. Filatov

Beilstein J. Org. Chem. 2025, 21, 500–509, doi:10.3762/bjoc.21.37

• packing mode. Extra precautions were taken to shield the compounds from light during synthesis, purification, and storage. After crystallizing each bimane, a vial containing multiple crystals was selected for irradiation studies. Cl2B (B), which showed 5% presence of the [2 + 2] dimer after

• is 0(0°), indicating that the reacting double bonds are coplanar and parallel. Furthermore, the intermolecular distances between the reacting carbons are identical. The distance between two carbon double bonds in Cl2B (B) was determined to be 3.487(4) Å (Table 1). The key question is why did Cl2B

• fluorescence spectrum and η is the refractive index of the solvent. Single crystal X-ray diffraction studies Crystals of Me4B, Cl2B (A), (B), (C), and Me2B were mounted on a MiTeGen micromount with NVH immersion oil. Data were collected from a shock-cooled single crystal at 100(2) K on a Bruker Apex Kappa Duo

Synthesis of N-acetyl diazocine derivatives via cross-coupling reaction

• Thomas Brandt,
• Pascal Lentes,
• Jeremy Rudtke,
• Michael Hösgen,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2025, 21, 490–499, doi:10.3762/bjoc.21.36

• switching properties even in an aqueous environment and are therefore promising switches in photopharmacological applications. a) Structural similarity of N-acetyl diazocine 1 with known 17βHSD3-inhibitor tetrahydrodibenzazocine (THB) [17] and parent diazocine with steroid scaffolds [18]. b) Parent

Synthesis of electrophile-tethered preQ₁ analogs for covalent attachment to preQ₁ RNA

• Laurin Flemmich and
• Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 483–489, doi:10.3762/bjoc.21.35

• ). Synthesis of preQ1 and DPQ1 derivatives with electrophilic handles For the synthesis of haloalkyl- and mesyloxyalkyl-modified preQ1 and DPQ1 ligands 3a,b and 4a–e (for target structures see Scheme 1), a divergent synthetic route was sought that provided flexibility with respect to linker length and nature

• , DPQ1) and haloalkyl-modified preQ1 and DPQ1. B) The ligand classes of XcnpreQ1 and XcnDPQ1 allow specific formation of covalent small molecule–RNA complexes as has been recently demonstrated (see ref. [4]). Electrophile (E). Three-step syntheses of preQ1 (1) and DPQ1 (2). For the synthesis of m6preQ1

• ) for synthetic contributions. Funding This work was funded in part by the Austrian Science Fund FWF [P31691, F8011-B] and the Austrian Research Promotion Agency FFG [West Austrian Bio NMR 858017].