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Search for "interaction" in Full Text gives 1253 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Asymmetric Mannich reaction of aromatic imines with malonates in the presence of multifunctional catalysts
Beilstein J. Org. Chem. 2026, 22, 151–157, doi:10.3762/bjoc.22.8
- led to the use of multifunctional catalysts of “homocooperativity,” where multiple units of the same catalyst perform different but complementary roles [17]. These catalysts employing noncovalent interactions via hydrogen bonds and also possess Lewis basic and π–π-interaction sites have been highly
- , entry 17), further highlighting the importance of the pyridine ring containing protecting group. The interaction between catalyst E and the imine was further investigated by 19F NMR studies (see Supporting Information File 1). To further elucidate the role of noncovalent interactions, we conducted
- strengthened via hydrogen-bond-assisted halogen bonding [26][30]. Similarly, hydrogen bonds with the amidic proton are also possible. The direct effect of a specific interaction could not be determined based on the obtained data. The network of noncovalent interactions formed stabilizes the complex between the
Symmetrical D–π–A–π–D indanone dyes: a new design for nonlinear optics and cyanide detection
Beilstein J. Org. Chem. 2026, 22, 131–142, doi:10.3762/bjoc.22.6
- theory (DFT) methods. The dyes also exhibit chemosensor properties, showing selectivity for cyanide via a Michael addition mechanism that causes the disappearance of the ICT band, and a significant color change was observed in both organic and aqueous media. In addition, the interaction mechanism between
- under ambient light. In addition, interaction mechanisms of dyes with cyanide were studied using the 1H NMR titration method, and it was determined that they interacted through an addition mechanism. Photophysical properties and interaction mechanisms of the compounds were also supported through density
- groups is disrupted. These results strongly suggest the addition of cyanide to the vinyl bridge. Furthermore, the color of dyes 2a–c, blue, green, and pink, respectively, under ambient light changed to yellow when interacting with cyanide. The interaction mechanism was determined by 1H NMR, and the
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
- substrate electronic environments [29]. Reactivity is governed by the electron density of arenes, which directly influences kinetics and product distributions [30][31]. The inability to generically modulate this interaction has confined most catalytic systems to narrow substrate scopes. Addressing this
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
- for the success of the reaction. DFT calculations suggested that in the transition state (TS1), a Cl–π interaction between the chlorine atom on the zirconocene catalyst and the aromatic ring of the substrate facilitated rapid halogen atom transfer (XAT), generating a radical at the C3 position of
- 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
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
- of nitric oxide (N2O2). These results allow us to think that the reaction pathway via nitrene C-s is less plausible compared to the interaction of radical A with 1a. Aliphatic nitro-NNO-azoxy compounds as potential NO donors and their in vitro fungicidal activity At the second part of our study, the
- of 0.1 V/s at 298 K. Free energy diagram of possible interaction pathways between 1a and dinitramide-derived radical A according to ωB97X-3c [94]/CPCM(MeCN) level of theory. Free energies ΔG and activation free energies ΔG≠ are given in kcal/mol. Dashed lines correspond to spin-state-changing
Competitive cyclization of ethyl trifluoroacetoacetate and methyl ketones with 1,3-diamino-2-propanol into hydrogenated oxazolo- and pyrimido-condensed pyridones
Beilstein J. Org. Chem. 2025, 21, 2716–2729, doi:10.3762/bjoc.21.209
- imine reaction center. This makes the center softer, which favors the interaction with the amino group to generate the hexahydropyrimidine intermediate C. The methyl, ethyl and butyl substituents of intermediate B have a positive inductive effect, which increases with the lengthening of the alkyl chain
Mechanistic insights into hydroxy(tosyloxy)iodobenzene-mediated ditosyloxylation of chalcones: a DFT study
Beilstein J. Org. Chem. 2025, 21, 2703–2715, doi:10.3762/bjoc.21.208
- , the interaction of [PhIOH]+ with C at α-position is weaker and is evident by longer C–I bond lengths in Int1, i.e., 3.06 Å and 3.14 Å for chalcones with X = -Cl, -NO2, respectively (Table 2). In fact, this interaction is much weaker for chalcone with X = -NO2 that the reaction between chalcone and
- interaction between chalcone and [PhIOH]+ for Int1 and Int2. The significant lengthening of the I–OH bond facilitates removal of the -OH group from Int2 to form Int3. The dissociation of I–OH is an important step in the reaction mechanism which plays a significant role in the overall reaction. The chemical
- transformation of Int2 to Int3 involves the interaction between lengthened the I–OH bond with [PhIOH]+ furnished by the second dissociated molecule of HTIB. This interaction with subsequent removal of H2O results in the formation of iodosobenzene. The formation of iodosobenzene makes the transformation of Int2
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
- )allylium tetrafluoroborate, which was then coupled to the C3 hydroxy group via Yamaguchi esterification. Global deprotection subsequently afforded ryanodine (1) in 10 steps, thus achieving this critical synthetic transformation. Although the interaction of ryanodine with intracellular calcium release
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
- portion of the nucleobase (the isoorotamide) simply dissolved, or rotated away from the binding pocket, not forming the intended interaction with distal A base in silico (Figure 7A). In the case of Db2, the amide NH in the linker was apparently too far from the PNA backbone and did not form the intended
- stabilizing H-bond but rather formed a hydrogen bond with the U in the U–A base pair (ca. 2.2 Å, Figure 7B). This interaction resulted in pushing the entire residue towards the RNA backbone where the Io base could further bind to a phosphate which likely explains why Db2 shows the lowest triplex stability of
- , heterocycle of Db2 is rotated, placing its polar face towards solute and non-polar methyl group towards RNA. This results in the whole Db2 base being tilted, which breaks the intended stabilizing H-bond between the Db2 linker and the adjacent M. Db3 resulted in the best interaction in silico despite the low
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
- occurred mainly within the first 10 minutes and then plateaued for the following hour, indicating that the initial interaction drives most of the perturbation. In contrast, 4-E continued to promote release over time, reflecting larger and sustained membrane disruption. Comparing isomers, the difference in
Synthesis of the tetracyclic skeleton of Aspidosperma alkaloids via PET-initiated cationic radical-derived interrupted [2 + 2]/retro-Mannich reaction
Beilstein J. Org. Chem. 2025, 21, 2470–2478, doi:10.3762/bjoc.21.189
- formation of IN1. The radical cation IN1 served as the reference point for DFT investigations. As illustrated in Figure 2a, facilitated by a favorable radical cation–π interaction [31], IN1 proceeds to the first radical addition transition state (TS1), with an energy barrier of 8.3 kcal/mol. This leads to
- ). Further geometrical adjustment and conformational restriction of the transient structure enable the N9 nonbonding p orbital to align parallel to the σ(C19–C3)* orbital (Figure 2f, TS2 → F-10 → F-40 → IN3), which reinforces the hyperconjugative interaction. Facilitated by the bond stretching and bond-angle
- bending of the transient structure with a pseudo bicyclo[2.2.0]hexane unit, the favorable hyperconjugative interaction ultimately leads to cleavage of the C19–C3 bond (TS2 → IN3) and release of the ring strain. DFT analysis hereby explains that the orbital symmetry involved in this process does not
The intramolecular stabilizing effects of O-benzoyl substituents as a driving force of the acid-promoted pyranoside-into-furanoside rearrangement
Beilstein J. Org. Chem. 2025, 21, 2456–2464, doi:10.3762/bjoc.21.187
- furanoside forms exhibit π–π interactions between the phenyl rings of some benzoate substituents. These are benzoates at O2 and O3 in the pyranoside and benzoates at O2 and O6 in the furanoside. Obviously the orientation of the C5–C6 in the furanoside greatly influences the possibility of such an interaction
- given in Table 1. Looking at the obtained conformations (Figure 5B), one can find that the same π–π interactions are present in the α-galactoside structures as in their β-isomers. However, there is a possibility of another interaction. This is the repulsion between the cis-oriented O-1 and O-2 atoms in
- rings. The internal C–C–C angles in them differ leading to more freedom for the side substituents in furanosides. This, in our opinion, means that the π–π interactions between the phenyl rings must increase in this case. However, a repulsive interaction that occurs between O-1 and O-2 oxygen atoms in
Transformation of the cyclohexane ring to the cyclopentane fragment of biologically active compounds
Beilstein J. Org. Chem. 2025, 21, 2416–2446, doi:10.3762/bjoc.21.185
- have been little studied, and are of interest to synthetic chemists. Thus, the interaction of (−)-metaphanine (70) with ammonia in CH3OH at room temperature led to the in situ formation of imine 72, which, as a result of an intramolecular aza-benzilic acid-type rearrangement, was converted in more than
- 10 μg/mL). Sequential interaction of indole 219 with pyridinium p-toluenesulfonate (PPTS) and excess of Davis’ oxaziridine 222, an effective oxidizing agent for synthesis of spirooxindole alkaloids, led to epoxide 220. Labile oxirane 220, without isolation, was subjected to a semipinacol
- unseparated mixture of abeolupanes 245 and 246, in a ratio of 1.5–3:1, with a total yield of 89%. The interaction of compound 243 with BF3·Et2O in benzene at 70 °C gave a mixture of olefins 245 and 246 in a 1:2 ratio, with an overall yield of 88%. Similar transformations were carried out with methyl
The high potential of methyl laurate as a recyclable competitor to conventional toxic solvents in [3 + 2] cycloaddition reactions
Beilstein J. Org. Chem. 2025, 21, 2389–2415, doi:10.3762/bjoc.21.184
- have been predicted for nitrone, with a δT (the Hildebrand solubility parameter or the total Hildebrand parameter) of approximately 17. This finding indicates that methyl laurate is a suitable solvent for nitrone, which has a δT of around 20. On the other hand, the radius of interaction (Ra) is a
- critical factor in the assessment of solute solubility in a solvent, particularly in the context of HSPs [97][98]. It facilitates estimation of the extent of interaction between a solute and solvent, as determined by their respective solubility parameters. Consequently, the difference between the HSPs
- approximately ≈ 6.57 MPa1/2. The radius of interaction (Ro) for a typical small organic molecule, such as the nitrone, is estimated to be approximately 7.5 MPa1/2 which value is usually determined for solute molecules [97][99]. The relationship between Ra and Ro is denoted by the term relative energy difference
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
- by the two structural analogs, we added a commercially available tetrabutylammonium salt (TBAI) to the body dissolved in CDCl3 (TBAI has a good solubility in CDCl3) and studied the interaction between the receptor and iodide ion by 1H NMR titration, UV–vis absorption spectroscopy and fluorescence
- groups inside the macrocycle and thus causes the NH peak to be shifted downfield. At the same time, after the addition of TBAI to the PBG solution, both proton signals c/d and e/f were shifted downfield, while protons a/b moved slightly to higher field, confirming the interaction between the anion and
- a/b and c/d both moved slightly to higher field. This indicates that there is a slight difference in the interaction between NH protons and iodine ions of the two structural analogs. Structural analysis showed that since the two single bonds are rotationally restricted, all its accessible
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
- the macrocycle interaction with the axle. In a different approach, the authors demonstrated that the macrocycle can shuttle along an axle by incorporating two acridane photoswitches at both ends. However, upon light activation, the macrocycle stops shuttling and remains in the middle of the axle
- –guest interaction induces a chiral signal, while the azobenzene chromophore imparts photoswitching properties to the molecule. Furthermore, solvent-mediated hydrogen-bonding interactions tailored within the inner cyclodextrin cavity, combined with photocontrolled isomerization of the azo moiety, enable
- the axle and allowed geometrical changes to occur, thereby modifying the nature and strength of the interaction between the macrocycle and the recognition sites [63][64]. Later, a new rotaxane was reported, which generates a strong induced circular dichroism response when the macrocycle is hydrogen
Insoluble methylene-bridged glycoluril dimers as sequestrants for dyes
Beilstein J. Org. Chem. 2025, 21, 2302–2314, doi:10.3762/bjoc.21.176
- , it is not possible to use 1H NMR to assess the geometry of the interaction between H2 or G2W1 with methylene blue or methylene violet, respectively. Determination of the adsorption capacity. Next, we wanted to learn more about the capacity of H2 and G2W1 for the removal of methylene blue and
Pathway economy in cyclization of 1,n-enynes
Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173
- acted as nucleophile, the stable imine–gold–aryl cation–π–π interaction precluded rearrangement and promoted the capture of imine to form spiro[indoline-3,3'-pyridine] derivatives 67. The Ph3PAuCl/AgNTf2-catalyzed cyclization of N-propargyl-tethered amide enynes efficiently afforded four distinct
Research towards selective inhibition of the CLK3 kinase
Beilstein J. Org. Chem. 2025, 21, 2250–2259, doi:10.3762/bjoc.21.172
- decided to prepare also the same molecules with hydrogen instead of the chlorine in meta position of the anilino group. Our previous work on DB18 suggested indeed that the chlorine atom is implicated in intramolecular halogen–π interaction, ending in a conformational constraint and ligand rigidity [24
- addition of the terminal acid significantly reinforces the interaction of our new molecules with CLK3, probably through a salt bridge with lysine 241. Logically, the corresponding esters are found to be inactive. Finally, in order to complete our profiling of VS-77, we then measured its activity against
- also evidenced by the better affinity for DYRK1A of the acidic molecules as compared to their ester analogues. Therefore, this new interaction could explain the higher affinity of VS-77 toward Hs_DYRK1A, as compared to DB-18. Conclusion In the present work, we disclosed a new strategy to improve the
Discovery of cytotoxic indolo[1,2-c]quinazoline derivatives through scaffold-based design
Beilstein J. Org. Chem. 2025, 21, 2062–2071, doi:10.3762/bjoc.21.161
- new indolo[1,2-c]quinazoline derivatives to interact with nucleic acids. Since not all compounds exhibited intrinsic fluorescence, we initially performed a screening using the fluorescent intercalator displacement (FID) assay. Only compounds 7a–c showed a positive response and interaction with DNA
- (Figure S1 in Supporting Information File 1). The interaction of compounds 7a–c with duplex DNA was then investigated by fluorescence titration, measuring the quenching of ligand fluorescence upon binding to the nucleic acid. Fluorimetric titration studies confirmed the interaction of 7a–c with double
- -stranded calf thymus DNA, as evidenced by ligand fluorescence quenching (Figure 2). Elongation of the linker in the carboxamide residue is accompanied by weaker DNA complexation (Table 4). The interaction of the compounds with DNA was found to be largely dependent on electrostatic forces. Reducing the
Asymmetric total synthesis of tricyclic prostaglandin D2 metabolite methyl ester via oxidative radical cyclization
Beilstein J. Org. Chem. 2025, 21, 1964–1972, doi:10.3762/bjoc.21.152
- a single diastereomer (Table 1, entry 4). To explain this diastereoselectivity, we hypothesize that the C–O bond, which occupies an axial position in the proposed transition state TS-1, could avert an additional hyperconjugative interaction (σ*C-O/π) that renders the reacting C=C bond electron
Synthesis, biological and electrochemical evaluation of glycidyl esters of phosphorus acids as potential anticancer drugs
Beilstein J. Org. Chem. 2025, 21, 1909–1916, doi:10.3762/bjoc.21.148
- . Electrochemical studies Alkylating agents are widely recognized for their ability to form covalent bonds with biological macromolecules (proteins, DNA). The literature discusses the interaction of small molecules with proteins, highlighting how linear sweep voltammetry (LSV) can be used to understand these
- themselves exhibit no discernible redox activity in this potential range when tested in the absence of HSA. Consequently, any changes in the recorded voltammogram could be attributed to the interaction (alkylation) of albumin rather than to new electrochemical processes arising directly from the compounds
Photoswitches beyond azobenzene: a beginner’s guide
Beilstein J. Org. Chem. 2025, 21, 1808–1853, doi:10.3762/bjoc.21.143
- of T-shaped 8a and 9a the Z-isomer was more thermally stable thanks to the weak interaction between the hydrogen and the π-system. However, the high symmetry weakens the intensity of the nπ* absorption band, which is the excitation band for the Z–E isomerisation, resulting in a lower E-PSS. Basic
- , giving better PSSs) and improved the half-lives without interfering too much with the absorption of the E-indigo (Figure 14). Diarylated indigos like 60g showed the presence of the Z-isomer in the dark, possibly due to the stabilisation energy given by the π–π interaction between the aryl rings (Figure
- (Scheme 33) [110]. The direct consequence of the planar 104 is the enhanced conjugation, which gives a red-shift in the absorption and favours the rotation mechanism (as seen in Scheme 32). The forced steric interaction of the aryl ring with the hydrazone moiety destabilises 105-E even further, decreasing
Research progress on calixarene/pillararene-based controlled drug release systems
Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139
- hydrophobic alkyl chain core. The assembly driving force directly relies on the host–guest interaction between WP6 and FC. Further studies have shown that by regulating the deprotonation/protonation state of the WP6 carboxyl groups through pH control, the reversible dissociation and reassembly of the vesicle
- chiral CA named chiral azo-calix[4]arene derivative (FC4AD) (Figure 10) [117]. Its interaction with enantiomers of aminoindanol in solution was investigated. It was found that FC4AD has high selective binding and release for (1R,2S)-1-amino-2-indanol, forming a 1:1 complex. S-phenethylamine was used as a
- inherent in non-covalent interactions. Building on biocompatibility studies, they also developed an enzyme-responsive supramolecular vesicle for treating Alzheimer's disease. This vesicle is assembled via the host–guest interaction between SC4A and myristoyl choline (Figure 13) [119]. The host–guest
Unique halogen–π association detected in single crystals of C–N atropisomeric N-(2-halophenyl)quinolin-2-one derivatives and the thione analogue
Beilstein J. Org. Chem. 2025, 21, 1748–1756, doi:10.3762/bjoc.21.138
- , Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama 337-8570, Japan 10.3762/bjoc.21.138 Abstract In single crystals of C–N atropisomeric N-(2-halophenyl)quinolin-2-one and the thione analogue, a unique association based on a halogen–π interaction was detected. In racemic and optically pure
- -electron on the quinolinone benzene ring, while that in optically pure forms is caused by an n–π* interaction between a lone electron pair on the halogen atom and a π* orbital of the quinolinone. In contrast to the formation of the homochiral layered polymer in quinolinones, in racemic N-(2-bromophenyl
- )quinoline-2-thione, heterochiral layered polymers, in which (P)- and (M)-atropisomers were alternately connected, were formed through an n–π* interaction between a lone electron pair on the bromine atom and a π* orbital of the quinoline-2-thione. Keywords: atropisomers; C–N bond; halogen bond; quinolinones
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