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Search for "B" in Full Text gives 3123 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Salen–scandium(III) complex-catalyzed asymmetric (3 + 2) annulation of aziridines and aldehydes

  • Linqiang Wang and
  • Jiaxi Xu

Beilstein J. Org. Chem. 2025, 21, 1087–1094, doi:10.3762/bjoc.21.86

Graphical Abstract
  • carboxylate groups followed by a ring opening of the aziridine ring, forming azomethine ylide intermediates A. The intermediates A further undergo a [2 + 3] annulation (or cycloaddition) with aldehydes 2 through endo transition state TS to generate intermediates B, which release products 3 with regeneration
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Published 28 May 2025

Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

  • Betty A. Kustiana,
  • Galuh Widiyarti and
  • Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

Graphical Abstract
  • vinylphenylboronic acid to synthesize the solid-supported phenylboronic acid catalyst (cat 1) which was used to convert cinnamic acid (7) to its corresponding amide 12 in moderate yield. The reaction involves dicarboxylate complex 135 formed through Lewis acid B–O=C interaction (Scheme 41A) [23]. The catalyst could
  • be reused multiple times without significant loss of activity. Using B(C6F5)3 as catalyst, Wu and co-workers (2021) developed a borane-catalyzed Fischer esterification of cinnamic acids with methanol to afford the corresponding methyl cinnamates 136 and 137 via (C6F5)3B–O=C interaction (138) (Scheme
  • -branched (L/B) selectivity of >20:1. The reaction involves the formation of palladium hydride (Pd–H) 270 as the key species followed by alkyne and CO insertion reactions via 271 and 272 (Scheme 68A) [116]. On the one hand, Jia and co-workers (2021) utilized environmentally benign water as the hydrogen
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Published 28 May 2025

Biobased carbon dots as photoreductants – an investigation by using triarylsulfonium salts

  • Valentina Benazzi,
  • Arianna Bini,
  • Ilaria Bertuol,
  • Mariangela Novello,
  • Federica Baldi,
  • Matteo Hoch,
  • Alvise Perosa and
  • Stefano Protti

Beilstein J. Org. Chem. 2025, 21, 1024–1030, doi:10.3762/bjoc.21.84

Graphical Abstract
  • solution was examined, for solubility reasons. a) CDs-mediated 1,2-difunctionalization of alkenes by alkyl halides R–Y and b) light-driven reduction of triarylsulfonium salts in the presence of CDs. Carbon dots tested in this project and their main (photo)physical characteristics. Emission parameters for
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Published 26 May 2025

Synthesis of pyrrolo[3,2-d]pyrimidine-2,4(3H)-diones by domino C–N coupling/hydroamination reactions

  • Ruben Manuel Figueira de Abreu,
  • Robin Tiedemann,
  • Peter Ehlers and
  • Peter Langer

Beilstein J. Org. Chem. 2025, 21, 1010–1017, doi:10.3762/bjoc.21.82

Graphical Abstract
  • instance, deazapurines represent heterocyclic fused pyrimidine bases which have found special attention, due to their widespread occurrence in natural alkaloids exhibiting various biological properties. For example, cadeguomycin (A), tubercidin (B), and toyocamycin (C) show antibiotic properties, while
  • activities. Development of drugs based on pyrrolopyrimidines: A: Cadeguomycin. B: Tubercidin. C: Toyocamycin. D: Batzelladine A. E: Sangivamycin. F: Pemetrexed. G: Immucillin H. H: TAK-285 (tyrosine kinase inhibitor). UV–vis absorption (left) and emission (right, λex = 300 nm) spectra of compounds 4a, 4j, 4k
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Published 22 May 2025

Recent total synthesis of natural products leveraging a strategy of enamide cyclization

  • Chun-Yu Mi,
  • Jia-Yuan Zhai and
  • Xiao-Ming Zhang

Beilstein J. Org. Chem. 2025, 21, 999–1009, doi:10.3762/bjoc.21.81

Graphical Abstract
  • cephalotaxine, cephalezomine H, (−)-cephalotaxine, (−)-cephalotine B, (−)-fortuneicyclidin A, (−)-fortuneicyclidin B, and (−)-cephalocyclidin A. Unlike enamines, tertiary enamides can participate in cyclization reactions initial as nucleophiles, and upon protonation, alkenylation, or alkylation, the resultant
  • a fragmentation process for the total synthesis of (−)-phlegmariurine B. A one-pot epoxidation/nucleophilic epoxide opening introduced both a hydroxy group and a chloride across the cyclopentene, producing 14 in 57% yield. After oxidation of alcohol 14 to ketone 15, the Mukaiyama hydration then
  • triggered a Grob fragmentation process of hemiaminal 16 and afforded the imide compound 17. Final regioselective reduction of one of the two carbonyls on the imide completed the synthesis of (−)-phlegmariurine B. Annulation Total syntheses of cephalotaxine and cephalezomine H The [2 + 3] annulation of
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Published 22 May 2025

On the photoluminescence in triarylmethyl-centered mono-, di-, and multiradicals

  • Daniel Straub,
  • Markus Gross,
  • Mona E. Arnold,
  • Julia Zolg and
  • Alexander J. C. Kuehne

Beilstein J. Org. Chem. 2025, 21, 964–998, doi:10.3762/bjoc.21.80

Graphical Abstract
  • -shifted and reduced in ϕ compared to TTM-Cz (cf. compounds 31 and 33 in Figure 8a and b). Higher generations (G3TTM, G4TTM) exhibit hypsochromically shifted emission maxima compared to the G2TTM and increased ϕ (52% and 63% respectively (in cyclohexane)) (see Figure 10). This effect can be explained by
  • extension of the Cz donor structure to benzocarbazole (BCz) and dibenzocarbazole (DbCz) follows the trend of the above described three-state model (see Figure 11). However, further extension to aza[7]helicenes also leads to contradiction with the model (cf. compounds 35 and 36 in Figure 8a and b). The ϕs of
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Published 21 May 2025

Harnessing tethered nitreniums for diastereoselective amino-sulfonoxylation of alkenes

  • Shyam Sathyamoorthi,
  • Appasaheb K. Nirpal,
  • Dnyaneshwar A. Gorve and
  • Steven P. Kelley

Beilstein J. Org. Chem. 2025, 21, 947–954, doi:10.3762/bjoc.21.78

Graphical Abstract
  • disulfonoxylation [2] and alkene amino-trifluoroacetoxylation [4], we hypothesized that treatment of (E)-hex-3-en-1-yl methoxycarbamate with a mixture of an I(III) oxidant and a sulfonic acid would lead to the formation of amino-sulfonoxylated product. We were thus very pleased to observe 59% of desired product B
  • using a combination of 1 equivalent of commercially available 1-acetoxy-1,2-benziodoxol-3-(1H)-one (CAS [1829-26-1]) and 1 equivalent of methanesulfonic acid (MsOH) (Table 1, entry 1). Increasing the equivalents of both reagents to 1.5 completely consumed starting material and delivered product B in an
  • excellent yield of 73% (Table 1, entry 2). A similar yield was achieved by using 1.5 equivalents of commercially available PhI(OH)(OMs) (CAS [105551-42-6]) (Table 1, entry 3). With these conditions, adding exogenous MsOH was not necessary. Reasonable amounts of product B could also be obtained with 1
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Published 19 May 2025

Study of tribenzo[b,d,f]azepine as donor in D–A photocatalysts

  • Katy Medrano-Uribe,
  • Jorge Humbrías-Martín and
  • Luca Dell’Amico

Beilstein J. Org. Chem. 2025, 21, 935–944, doi:10.3762/bjoc.21.76

Graphical Abstract
  • nitrogen donors have gained increasing attention for their use as photoredox catalysts. This study introduces a new family of D–A molecules by exploring various sulfur-based acceptors and nitrogen donors, including a novel tribenzo[b,d,f]azepine (TBA) unit and 5H-dibenz[b,f]azepine (IMD). Our findings
  • -donating strength. The development of stronger donors to enhance luminescence remains a key area of research [20][21][22]. Recently, azepine-based analogs, such as tribenzo[b,d,f]azepine (TBA, a), have been explored due to their photoluminescence properties [23][24][25][26][27]. This antiaromatic core
  • offers unique features, including twisted structures, reduced π–π stacking, and enhanced reverse intersystem crossing rates, becoming a better donor compared to fully planar compounds as carbazole (c). Similarly, 5H-dibenz[b,f]azepine (IMD, b) has been incorporated into D–A–D structures, showing
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Published 14 May 2025

A convergent synthetic approach to the tetracyclic core framework of khayanolide-type limonoids

  • Zhiyang Zhang,
  • Jialei Hu,
  • Hanfeng Ding,
  • Li Zhang and
  • Peirong Rao

Beilstein J. Org. Chem. 2025, 21, 926–934, doi:10.3762/bjoc.21.75

Graphical Abstract
  • simultaneously installing the hydroxy group at C30. The latter intermediate could in turn be derived from dienone 11 by an AcOH-interrupted Nazarov cyclization [32][33][34], thereby establishing the B ring with the desired all-cis stereochemical configuration, including the quaternary carbon at C10 and the
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Published 12 May 2025

Silver(I) triflate-catalyzed post-Ugi synthesis of pyrazolodiazepines

  • Muhammad Hasan,
  • Anatoly A. Peshkov,
  • Syed Anis Ali Shah,
  • Andrey Belyaev,
  • Chang-Keun Lim,
  • Shunyi Wang and
  • Vsevolod A. Peshkov

Beilstein J. Org. Chem. 2025, 21, 915–925, doi:10.3762/bjoc.21.74

Graphical Abstract
  • activated alkyne in an endo-dig fashion, forming a 7-membered ring. The resulting intermediate B undergoes proton transfer from the second pyrazole nitrogen to the vinyl silver moiety yielding pyrazolo[1,5-a][1,4]diazepine 16a and regenerating the silver catalyst. Methylation of either pyrazole nitrogen
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Published 08 May 2025

Recent advances in controllable/divergent synthesis

  • Jilei Cao,
  • Leiyang Bai and
  • Xuefeng Jiang

Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73

Graphical Abstract
  • the σ-alkylpalladium intermediate Int-50. The intermediate Int-50 undergoes C–H activation to generate the spiro-palladacycle Int-51, which proceeds via two possible pathways: 1) Path a: oxidative addition/reductive elimination or 2) path b: transmetalation/reductive elimination giving rise to
  • reduced electrophilicity of the ester carbonyl. In 2021, Dong and Xie reported the development of an azido Matteson reaction, which achieves carbene insertion into an N–B bond of aminoboranes 84 or 86 (Scheme 22) [53]. In this methodology, by controlling the carbene leaving group (alkyl chlorides/alkyl
  • while regenerating the catalytic species Int-82. Comparative kinetic analysis revealed a marked preference for alkyl iodide activation, as demonstrated by its substantially lower activation energy barrier compared to alkyl bromide analogs (path b). This energetic advantage facilitates preferential
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Published 07 May 2025

Dicarboxylate recognition based on ultracycle hosts through cooperative hydrogen bonding and anion–π interactions

  • Wen-Hui Mi,
  • Teng-Yu Huang,
  • Xu-Dong Wang,
  • Yu-Fei Ao,
  • Qi-Qiang Wang and
  • De-Xian Wang

Beilstein J. Org. Chem. 2025, 21, 884–889, doi:10.3762/bjoc.21.72

Graphical Abstract
  • introduction of lower-rim hydroxy substituents effectively enhances the dicarboxylate binding through cooperative hydrogen bonding and anion–π interactions. The selective recognition of long and flexible dicarboxylates holds exciting promise for the use of dicarboxylate sensors in medicine and industry. (a, b
  • ) Crystal structure of B4aH (hydrogen atoms are omitted for clarity), and (c) the stacking structure of the crystal of B4aH (the blue dotted lines represent hydrogen bonds). (a) The structures of host and guests, (b) 1H NMR spectra (298 K, 400 MHz, CD3CN) of B4aH upon titration with C62− (c(B4aH) = 1 mM
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Published 06 May 2025

Cu–Bpin-mediated dimerization of 4,4-dichloro-2-butenoic acid derivatives enables the synthesis of densely functionalized cyclopropanes

  • Patricia Gómez-Roibás,
  • Andrea Chaves-Pouso and
  • Martín Fañanás-Mastral

Beilstein J. Org. Chem. 2025, 21, 877–883, doi:10.3762/bjoc.21.71

Graphical Abstract
  • species A which is in equilibrium with the Cu–O enolate B [11]. In the presence of excess of LiOt-Bu, a salt metathesis reaction between this base and intermediate B generates lithium enolate C and LCuOt-Bu to close the copper catalytic cycle. The formation of a lithium enolate is consistent with the
  • mechanism for the Cu-catalyzed dimerization of 4,4-dichoro-2-butenoic acid derivatives. a) KOt-Bu-mediated intramolecular cyclization of 9. b) Direct formation of cyclopropane 20 from gem-dichloride 5 using KOt-Bu as base. Optimization studies. Synthesis of densely functionalized (2,2-dichlorovinyl
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Published 05 May 2025

Data accessibility in the chemical sciences: an analysis of recent practice in organic chemistry journals

  • Sally Bloodworth,
  • Cerys Willoughby and
  • Simon J. Coles

Beilstein J. Org. Chem. 2025, 21, 864–876, doi:10.3762/bjoc.21.70

Graphical Abstract
  • at least two types of data (Figure 2a,b). Commonly, studies generated NMR data (93%) and mass spectrometry (MS) data (87%) as these are the minimum requirement for compound characterization in all journals (Figure 2c). Are unprocessed primary data included? (Access_3) 239 of the 240 articles produced
  • shared data with FAIR principles. FAIR variable codes with the form ‘Name_integer’ are defined in Table 2. Proportions of articles that a) meet and b) exceed, publisher data requirements. Specialist organic chemistry journals selected for this study. FAIR variables assessed in the analysis.a Supporting
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Published 02 May 2025

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

Graphical Abstract
  • 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
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Published 30 Apr 2025

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

Graphical Abstract
  • 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
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Published 29 Apr 2025

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

Graphical Abstract
  • (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
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Published 28 Apr 2025

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

Graphical Abstract
  • -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
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Published 25 Apr 2025

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

Graphical Abstract
  • 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
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Published 24 Apr 2025

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

Graphical Abstract
  • 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
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Published 22 Apr 2025

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

Graphical Abstract
  • 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
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Published 17 Apr 2025

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

Graphical Abstract
  • 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
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Published 14 Apr 2025

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

Graphical Abstract
  • 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
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Published 08 Apr 2025

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

Graphical Abstract
  • 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
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Published 04 Apr 2025

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

Graphical Abstract
  • 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
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Published 03 Apr 2025
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