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Search for "control" in Full Text gives 1585 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Configuration–packing synergy enabling integrated crystalline-state RTP and amorphous-state TADF
Beilstein J. Org. Chem. 2026, 22, 224–236, doi:10.3762/bjoc.22.16
- , lifetime, and efficiency, make them highly versatile for integration into advanced optoelectronic devices [9][10][11]. The performance limits of these devices, particularly in terms of their brightness, longevity, and efficiency, are largely dependent on the ability to precisely control the dynamics of the
- and exploring its potential applications in various optoelectronic devices. The ability to control and utilize both fluorescence and phosphorescence in 1 opens up promising avenues for future research, particularly in the development of advanced materials for light-emitting devices. At room
Screwing the helical chirality through terminal peri-functionalization
Beilstein J. Org. Chem. 2026, 22, 205–212, doi:10.3762/bjoc.22.14
- ; Introduction Nature utilizes helical chirality for the inception of life. The double-helical structure of DNA and the helical conformations of proteins are key examples of the helical chirality. Inspired by these natural systems, chemists have developed methods to construct and control helicity in synthetic
- , biosensors and other forms of the materials sciences continuing its relevance to cutting edge research [1][2]. However, precise control and manipulation of helical chirality in synthetic systems remain technically challenging. This complexity may have led to underestimation of its potential, as research
- in their core structure [8]. Point chirality is the simplest form of chirality, and it is relatively easy to control and characterize during the synthesis of organic molecules. Due to these facts point chirality holds a central position among the different types of chirality. Axial chirality is
Base-promoted deacylation of 2-acetyl-2,5-dihydrothiophenes and their oxygen-mediated hydroxylation
Beilstein J. Org. Chem. 2026, 22, 192–204, doi:10.3762/bjoc.22.13
- cyclooctano-spiroannulated dihydrothiophenes 4a–f were transformed into products 5a–f in 58–90% yield. Piperidine- and azepane-substituted cyclooctano-spiroannulated dihydrothiophenes 4e,f also transformed into deacylated products 5e,f in 71% and 89% yield, respectively. Several control experiments were
- (0.13–0.22 mmol, 1.0 equiv), sodium (0.66–1.11 mmol, 5 equiv), dry EtOH (2.5–3.0 mL). Control experiments. Proposed mechanism. Optimization of the transformation of dihydrothiophene 1a.a Optimization of the transformation of dihydrothiophene 4a.a Supporting Information Supporting Information File 17
Streptoquinolines A and B, new antibacterial meroterpenoids produced by Streptomyces sp. TMPU-A0679
Beilstein J. Org. Chem. 2026, 22, 185–191, doi:10.3762/bjoc.22.12
- incubated at 37 °C for 24 hours. Bacterial growth was assessed by measuring turbidity at 550 nm using a spectrophotometer. The MIC was defined as the lowest concentration of the test compound that inhibited ≥90% of bacterial growth relative to the control (no compound). Structures of streptoquinolines A (1
Improved synthesis and physicochemical characterization of the selective serotonin 2A receptor agonist 25CN-NBOH
Beilstein J. Org. Chem. 2026, 22, 175–184, doi:10.3762/bjoc.22.11
- (Agilent Technologies). Cary WinUV Simple Reads Application (Version 5.0.0, Agilent Technologies) was used for instrument control and data collection. The experiment was performed in triplicate. Stability in solution The stability of 1 was determined in 67 mM sodium phosphate buffer (pH 7.40, I = 0.18 M
- , respectively, while UV–vis spectra were recorded using the fiber optic probe (10 mm light path) of the inForm diode array spectrometer. The instrument control and data analysis were performed using the inForm software Version 1.1.3.6 (Sirius Analytical, Forest Row, UK). HPLC Samples from distribution
- and 0.1% phosphoric acid in the ratios 35:65 and 25:75, v/v for the distribution coefficient and stability experiments, respectively. The ChemStation software (Version B.04.03, Agilent Technologies) was used for instrument control and data collection. Computational chemistry DFT calculations were
Total synthesis of natural products based on hydrogenation of aromatic rings
Beilstein J. Org. Chem. 2026, 22, 88–122, doi:10.3762/bjoc.22.4
- building blocks used in natural product syntheses are often difficult to prepare or scale-up, constrained by subtle chemical reactivity, functional group compatibility, and control of stereoselectivity. Together, these factors continue to shape the pursuit of concise and practical synthetic routes to
- electrochemical systems, have expanded the toolbox further by enabling reductive dearomatization under exceptionally mild conditions and with high functional-group compatibility. Collectively, these hydride- and electron-transfer approaches enrich the landscape of arene reduction by providing tunable control over
- mechanistic hypothesis. Based on this stereochemical control, the Stoltz team successfully obtained the asymmetric hydrogenation product 176, which spontaneously underwent intramolecular cyclization to furnish the bridged cyclic compound 177. With compound 177 in hand, a series of three transformations
Advances in Zr-mediated radical transformations and applications to total synthesis
Beilstein J. Org. Chem. 2026, 22, 71–87, doi:10.3762/bjoc.22.3
- remains widely used today as a reducing agent [3] (Figure 1). In recent years, this accessibility, together with advances in radical chemistry, has motivated many researchers to investigate control of radical reactions using zirconium. A particularly important physical property of zirconium is its large
- presence of a Cl–π interaction, which facilitates the facile XAT process. Since this step is accompanied by the formation of a strong Zr–Br bond [12], the overall process is exothermic (ΔGrxn = −22.6 kcal/mol) and provides the thermodynamic driving force for the reaction. Next, control experiments were
Synthesis and applications of alkenyl chlorides (vinyl chlorides): a review
Beilstein J. Org. Chem. 2026, 22, 1–63, doi:10.3762/bjoc.22.1
- ). Thus, the reaction is synthetically valuable but necessitates careful control of reagent quantities and reaction conditions for optimal yields. Chemists from Alkaloida reported that 4-chromanones undergo transformation to the corresponding 4-halo-2H-chromenes upon treatment with PCl3 (Scheme 17) [70
- discrepancy to product degradation during purification on neutralized silica gel (1% NEt₃) or neutral alumina. However, this hypothesis was not experimentally verified, as no control experiment involving the passage of a pure, non-volatile alkenyl chloride through the purification media was reported to assess
- excellent stereochemical control using NCS (Scheme 29F) [119]. Kigoshi reported the reaction of alkenylsilane with NCS to afford compound 176 which served as building block for the total synthesis of 15-epi-haterumalide NA (Scheme 29G) [120]. Interestingly, the transformation of alkenylsilanes to alkenyl
Sustainable electrochemical synthesis of aliphatic nitro-NNO-azoxy compounds employing ammonium dinitramide and their in vitro evaluation as potential nitric oxide donors and fungicides
Beilstein J. Org. Chem. 2025, 21, 2739–2754, doi:10.3762/bjoc.21.211
- , electroorganic synthesis has become a powerful and reliable strategy for the functionalization of organic compounds under green and mild reaction conditions [36][37][38][39]. The control of selectivity through the variation of parameters such as current, voltage, electrolyte, electrodes, and the type of
- product nitro-NNO-azoxy propane 2a exhibits an oxidation peak at +1.68 V (Figure 2, pink curve). Despite the lower oxidation potential of 2a, we speculate that an excess of ADN suppresses competitive oxidation of the reaction product. To gain insight into the reaction mechanism, control experiments were
- calculations were performed [93] on ωB97X-3c [94] /CPCM(MeCN) level of theory (Figure 3). Based on cyclic voltammetry data, control experiments, and our previous study, the mechanism of the electrochemical synthesis of nitro-NNO-azoxy compounds 2 was proposed (Figure 3, Scheme 5). The reaction starts from
Total synthesis of asperdinones B, C, D, E and terezine D
Beilstein J. Org. Chem. 2025, 21, 2730–2738, doi:10.3762/bjoc.21.210
- ]. For example, using 1 equivalent of reagent 29, the cross-coupling of 3-iodo-6-prenyl-N-acetylindole (27) led to the adduct 32 in 52% yield accompanied by the reduced product 37 in 30% and the dehydro product 38 in 10% yield. Control experiments revealed that the iodozinc reagent from 29 was unaffected
- - and allylindoles. Markovnikov hydrochlorination and hydrotrifluoroacetylation. Synthesis of asperdinones B–E 1–4. Control experiment. Control experiment of the Negishi cross-coupling reaction. Synthesis of terezine D and ent-asperdinone E. Supporting Information Supporting Information File 18
Recent advancements in the synthesis of Veratrum alkaloids
Beilstein J. Org. Chem. 2025, 21, 2657–2693, doi:10.3762/bjoc.21.206
Silica gel with covalently attached bambusuril macrocycle for dicyanoaurate sorption from water
Beilstein J. Org. Chem. 2025, 21, 2604–2611, doi:10.3762/bjoc.21.201
- ; gold mining; macrocycles; Introduction Inorganic anions play essential roles in a variety of biological and biochemical mechanisms and are also involved in many industrial and manufacturing processes. Due to their significant environmental impact, it is important to monitor their presence and control
Total syntheses of highly oxidative Ryania diterpenoids facilitated by innovations in synthetic strategies
Beilstein J. Org. Chem. 2025, 21, 2553–2570, doi:10.3762/bjoc.21.198
- pericyclic reactions [31][32][33][34][35][36][37][38][39][40][41][42][43][44], to control the formation of the crucial C5 chiral center precisely. Subsequent oxidative cleavage of the carbon–carbon double bond introduced in the Diels–Alder reaction, followed by an intramolecular aldol reaction, efficiently
Rapid access to the core of malayamycin A by intramolecular dipolar cycloaddition
Beilstein J. Org. Chem. 2025, 21, 2542–2547, doi:10.3762/bjoc.21.196
- as alternatives to existing fungicides as well as enhancing the control spectrum and persistence [3]. A group of scientists at Syngenta reported a bicyclic perhydrofuropyran C-nucleoside malayamycin A (1) from the soil bacterium Streptomyces malaysiensis [4] (Figure 1). This novel compound was found
Synthesis and characterization of a isothiouronium-calix[4]arene derivative: self-assembly and anticancer activity
Beilstein J. Org. Chem. 2025, 21, 2535–2541, doi:10.3762/bjoc.21.195
- compound 3 than healthy, non-malignant cells. In general, SI values above 12 are associated to remarkable selectivity, 6–12 to moderate selectivity and 1–5 to weak selectivity [43][47]. In contrast, the potent antineoplastic agent doxorubicin, used as the positive control for anticancer effects, did not
- the acridine orange staining assay. Briefly, cancer cells were seeded in 96-well plates and grown at optimum culture conditions for 72 h (at a confluence of ≈60–80%). Then, cells were treated with the indicated concentrations of compounds for additional 48 h. Control cells received an equal volume of
- kinetics in renal cancer 786O and skin fibroblast WS1 cells. Data represent the percentage of proliferation with respect to the correspondent vehicle DMSO controls. ***, p < 0.001 vs the respective vehicle control by 2-way ANOVA; ###, p < 0.001 vs correspondent WS1 conditions by 2-way ANOVA. B) Calculated
Pentacyclic aromatic heterocycles from Pd-catalyzed annulation of 1,5-diaryl-1,2,3-triazoles
Beilstein J. Org. Chem. 2025, 21, 2524–2534, doi:10.3762/bjoc.21.194
- observed for these annulated molecules, while their analogous non-annulated control compounds were not bioactive. Keywords: annulation; arenes; antimicrobials; fused-ring systems; UV–vis spectroscopy; Introduction Polycyclic aromatic heterocycles are a diverse class of small molecules with utility in a
- been reported. 1,5-Diaryl-1,2,3-triazole control compounds 37–42 were prepared via tandem deprotection/click reactions of TMS-protected alkynes with phenyl azide in yields similar to bromophenyl annulation precursors 7–12 and 25–30. Compounds 43–48, inverting the diaryltriazole connectivity, were
- signals in the aromatic region shift downfield significantly following annulation relative to both the bromoaryl synthetic precursor and control compound. Figure 5 illustrates this general trend by comparing annulated 18 with both its precursor 12 and its non-annulated control 42. Overall, each signal in
Isoorotamide-based peptide nucleic acid nucleobases with extended linkers aimed at distal base recognition of adenosine in double helical RNA
Beilstein J. Org. Chem. 2025, 21, 2513–2523, doi:10.3762/bjoc.21.193
- nucleobases that showed enhanced triplex stability through cooperative effects compared to the control thymine base. In a follow up study, the pendant amide was removed from the Io core to determine the importance of the third hydrogen bond. To our surprise, these second-generation Io derivatives retained
Effect of a photoswitchable rotaxane on membrane permeabilization across lipid compositions
Beilstein J. Org. Chem. 2025, 21, 2498–2512, doi:10.3762/bjoc.21.192
- bacteria or malignant cells like cancer) [5][6], or to influence membrane protein function and thereby control cellular behavior [7][8]. One promising approach is the development of light-activated molecules that can modulate membrane properties upon irradiation, enabling remote activation with high
- permeabilization was assessed by monitoring the release of encapsulated sulforhodamine B dye, serving as a reporter for membrane perturbation. Specifically, we examined LUVs in the liquid-disordered (Ld), liquid-ordered (Lo), and gel (Lβ) phases. As control molecules, we also investigated the membrane perturbation
- , control rotaxane 2 [13] has the same dibenzo 24-crown-8 ring but lacks the azobenzene units. Both rotaxanes use axle 3, which consists of an amphiphilic chain with three positively charged sites serving as recognition sites for the macrocycle: two benzylalkylammonium groups (BAA) and one N
Palladium-catalyzed regioselective C1-selective nitration of carbazoles
Beilstein J. Org. Chem. 2025, 21, 2479–2488, doi:10.3762/bjoc.21.190
- failed to enhance the product 2a yield (Table 1, entry 10). Attempts to optimize the reaction temperature did not yield improvements either (Table 1, entry 11). Control experiments confirmed that both the palladium catalyst and AgNO3 are essential for the reaction to proceed, as omission of either
- 2-pyridyl group emerged as the most effective, enabling regioselective C1–H nitration to afford product 2a. Notably, control experiments using N-aryl-/N-alkyl-protected carbazoles and N-unsubstituted carbazole under standard conditions failed to produce the desired product. Substrate scope With the
Ex-situ generation of gaseous nitriles in two-chamber glassware for facile haloacetimidate synthesis
Beilstein J. Org. Chem. 2025, 21, 2465–2469, doi:10.3762/bjoc.21.188
- their subsequent reaction with O-nucleophiles in the second chamber. The method is easy to setup, control and gives access to new haloacetimidates under mild conditions, similar to the ones used for the synthesis of the more commonly used trichloroacetimidates. Keywords: gaseous reagents; glycosyl
Conformational effects on iodide binding: a comparative study of flexible and rigid carbazole macrocyclic analogs
Beilstein J. Org. Chem. 2025, 21, 2369–2375, doi:10.3762/bjoc.21.181
- . Additionally, as a control experiment, the interaction between carbazole molecules and iodide ions via UV–vis and PL spectroscopy (Figures S14 and S15 in Supporting Information File 1) were investigated. The results revealed no analogous regular trends, and the interactions could not be effectively modeled
Rotaxanes with integrated photoswitches: design principles, functional behavior, and emerging applications
Beilstein J. Org. Chem. 2025, 21, 2345–2366, doi:10.3762/bjoc.21.179
- for precise control over their structural, dynamic, and functional properties. By harnessing light as a non-invasive stimulus with high spatial and temporal resolution, these photoswitches allow for the modulation of the rotaxanes’ intra- and intermolecular interactions, optoelectronic properties, and
- resulting influence on rotaxane operation. Due to their architectural versatility and precise light control, photoswitchable rotaxanes hold promise for a broad range of applications, including light-responsive molecular machines, smart materials, and biofunctional systems. However, emerging applications
- increasingly require rethinking and developing new structural designs that incorporate more efficient and advanced photoswitches to fully realize their potential. Keywords: macrocycle; photoisomerization; photoswitches; rotaxanes; shuttling; Introduction Harnessing light energy to control intra- and
Enantioselective radical chemistry: a bright future ahead
Beilstein J. Org. Chem. 2025, 21, 2283–2296, doi:10.3762/bjoc.21.174
- synthesis. Strategies for asymmetric radical reactions Stereoselectivity in radical reactions can be challenging to control. Many radicals are highly reactive, and radicals moreover have typically low inversion barriers, resulting in no permanent chirality at the radical center. Stereochemistry in radical
- reactions An emerging trend in the field of enantioselective radical transformations is the use of enzymatic catalysis to control absolute stereoselectivity. Some remarkable transformations have been demonstrated using this promising greener catalysis. This methodology has a bright future when used
Pathway economy in cyclization of 1,n-enynes
Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173
- substrate class. Through mechanistic-guided modulation of catalysts, solvents, ligands, and angle strain, this approach achieves unprecedented reaction pathway control while demonstrating superior temporal and step efficiency compared to conventional methods. The work establishes a sustainable framework for
- transition states. This integrated control framework provides a rational basis for designing reaction conditions to optimize selectivity and efficiency in organic synthesis. In 2014, the Liu group developed an Au(I)-catalyzed cascade cyclization strategy for synthesizing polysubstituted naphthalenes using
- -catalyzed cyclization approach using aromatic enyne derivatives, where substituent control governed the stereoselective syntheses of naphthalene and indene cores (Scheme 7) [14]. When the alkyne terminus of the substrate 27 bore an alkyl or aryl substituent, the Ph3PAuCl/AgOTf-catalyzed 6-endo-dig
Pd-catalyzed dehydrogenative arylation of arylhydrazines to access non-symmetric azobenzenes, including tetra-ortho derivatives
Beilstein J. Org. Chem. 2025, 21, 2234–2242, doi:10.3762/bjoc.21.170
- as an oxidant, combined with NaH as the base, increased the formation of 3a, achieving GC yields of up to 65% (Table 1, entry 3). Control experiments demonstrated that palladium, phosphine, and base were all essential for this reaction (Table S4 in Supporting Information File 1). However, under
- batch of Cs2CO3 showed a dramatic reduction in product yield (Table 1, entry 12). Control experiments with varying amounts of water (0–10 equiv) demonstrated that a small amount of water is crucial for the reaction (Supporting Information File 1, Table S7 and Table 1, entry 11). This effect, previously
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