Enhanced host–guest interaction between [10]cycloparaphenylene ([10]CPP) and [5]CPP by cationic charges

• Eiichi Kayahara,
• Yoshiyuki Mizuhata and
• Shigeru Yamago

Beilstein J. Org. Chem. 2024, 20, 436–444, doi:10.3762/bjoc.20.38

• function. After our first report on the selective encapsulation of C60 by [10]CPP (the number in the brackets is the number of paraphenylene units in the CPP) (Figure 1a) [22], the concave inner surface of CPPs was found to interact with a variety of molecules with convex surfaces through π–π interactions

Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

• Periklis X. Kolagkis,
• Eirini M. Galathri and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

• prostate cancer. The same apoptotic function can be observed in colon and pancreatic cancer, since BIMs (specifically DIM-C-pPhOCH3 (5)) can act as a Nur77 (Nuclear Receptor 4A1) antagonist, which modulates the life cycle of cells [6]. The correlation between lower lung cancer risk and the consumption of

• cruciferous vegetables has also been showcased, due to the function of BIMs as oxidative stress inhibitors; however, the specific mechanism of action has yet to be determined [1][6]. This capability of BIMs to act as Nur77 antagonists, has resulted in their examination as potential anti-Parkinson’s disease

• antiviral properties. BIMs function as selective antibacterial agents against several virulent Escherichia coli (E. coli) strains, which can cause many gut and urinary tract infections. They act by damaging DNA molecules and inhibiting their replication in bacteria, while also targeting the proteins that

Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

• Eugeny Ivakhnenko,
• Vasily Malay,
• Pavel Knyazev,
• Nikita Merezhko,
• Nadezhda Makarova,
• Oleg Demidov,
• Gennady Borodkin,
• Andrey Starikov and
• Vladimir Minkin

Beilstein J. Org. Chem. 2024, 20, 336–345, doi:10.3762/bjoc.20.34

•  1), the energetically preferred tautomer is the 14H-form 7a. The least stable 7H-isomer 7b conforms to a minimum on the corresponding potential energy surface. However, the stable wave function of 7b corresponds to an electronic state with a broken symmetry [20], indicating the presence of two

• the geometry without imposing symmetry restrictions, followed by analyzing the stability of the DFT wave function. The images of the molecular structures in Figure 1 and Figure S6, Supporting Information File 1, were obtained using the Chemcraft program [35]. DFT-calculated molecular geometry (B3LYP/6

Elucidating the glycan-binding specificity and structure of Cucumis melo agglutinin, a new R-type lectin

• Jon Lundstrøm,
• Emilie Gillon,
• Valérie Chazalet,
• Nicole Kerekes,
• Antonio Di Maio,
• Ten Feizi,
• Yan Liu,
• Annabelle Varrot and
• Daniel Bojar

Beilstein J. Org. Chem. 2024, 20, 306–320, doi:10.3762/bjoc.20.31

• and tissues, thereby offering insights into cellular heterogeneity and function. For instance, the use of wheat germ agglutinin (WGA) and concanavalin A (ConA) has been instrumental in selectively staining cells based on their glycan expression [4], including single-cell approaches [5][6]. In the

• in which its preferred binding motifs occur (O-glycans, milk glycans, GAGs) are absent from most plants, including melons. We thus hypothesize that the role of this lectin might be to recognize non-self epitopes, such as for protection against pathogens, which is a common function in plant lectins [3

• and the range of their binding specificities, but also our knowledge of melon lectins in particular, which has remained limited so far. Further experiments are still required to determine the role of the C-terminal domain, as well as the physiological function of the full-length CMA1 protein

Tandem Hock and Friedel–Crafts reactions allowing an expedient synthesis of a cyclolignan-type scaffold

• Viktoria A. Ikonnikova,
• Cristina Cheibas,
• Oscar Gayraud,
• Alexandra E. Bosnidou,
• Nicolas Casaretto,
• Gilles Frison and
• Bastien Nay

Beilstein J. Org. Chem. 2024, 20, 162–169, doi:10.3762/bjoc.20.15

• are excellent substrates for such reactions, affording electrophilic carbonyl derivatives susceptible to react with nucleophiles in the acidic reaction mixture [4][5][6][7][8]. Consequently, the Hock rearrangement is likely to be part of tandem processes involving this carbonyl function [9][10][11

• surrogate of the aldehyde function when it is engaged in a tandem photooxygenation and Hock rearrangement, involving allylic hydroperoxide intermediates in an acidic medium. In the presence of aromatic nucleophiles, the aldehyde intermediate of the Hock rearrangement can be involved in tandem Friedel–Crafts

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• cyclopentadiene moieties. TCBD 4, obtained through the [2 + 2] CA–RE reaction, continues to function as an electron-accepting alkene, as shown in Scheme 4. Subsequent [2 + 2] CA–RE reactions involving electron-rich alkynes yield tetracyano-1,3,5-hexatrienes (TCHTs). These reactions occur seamlessly in a one-pot

Electron-beam-promoted fullerene dimerization in nanotubes: insights from DFT computations

• Laura Abella,
• Gerard Novell-Leruth,
• Josep M. Ricart,
• Josep M. Poblet and
• Antonio Rodríguez-Fortea

Beilstein J. Org. Chem. 2024, 20, 92–100, doi:10.3762/bjoc.20.10

• gas phase; the C60 + C60 dimerization is slightly endothermic with a barrier around 30 kcal mol−1, whereas dimerization for the radical cation is exothermic with a tiny (or almost nil) barrier, which makes this initial step of the reaction drastically faster. Therefore, the main function of the CNT is

Optimizing reaction conditions for the light-driven hydrogen evolution in a loop photoreactor

• Pengcheng Li,
• Daniel Kowalczyk,
• Johannes Liessem,
• Mohamed M. Elnagar,
• Dariusz Mitoraj,
• Radim Beranek and
• Dirk Ziegenbalg

Beilstein J. Org. Chem. 2024, 20, 74–91, doi:10.3762/bjoc.20.9

• coefficient, c is the concentration of a light-absorbing solute, and d is the optical path length. Figure 8 shows the measured absorbance as function of the photocatalyst loadings in the methanol/water solution using different optical path lengths. The absorbance depends linearly on the photocatalyst

• generation rate as function of irradiation time. The hydrogen generation rate first increases to a maximum value and decreases subsequently. After around 10 hours of irradiation, a steady level of hydrogen evolution is reached. Even though some fluctuations in the range of ±8% can be observed, the hydrogen

• different irradiation time, (b) photon flux at different irradiation time. Photon flux in the loop reactor with respect to the LED electrical current. Absorbance as function of photocatalyst loading for different optical path lengths. Long-term operation of the loop photoreactor. Visualization of the

Preparing a liquid crystalline dispersion of carbon nanotubes with high aspect ratio

• Keiko Kojima,
• Nodoka Kosugi,
• Hirokuni Jintoku,
• Kazufumi Kobashi and
• Toshiya Okazaki

Beilstein J. Org. Chem. 2024, 20, 52–58, doi:10.3762/bjoc.20.7

• ][30]. If the DWCNTs align parallel to the long axis of the spindle droplet, it is referred to as a homogenous tactoid. Conversely, if the DWCNTs align from one pole to another, it is called a bipolar tactoid. Figure 3 illustrates the aspect ratio of the tactoids (R/r) as a function of the tactoid

• concentration against the CNT aspect ratio L/D of three CNT-SC aqueous dispersions [22][23]. Dashed lines indicate the results of curve fitting by inverse function in each phase transition, from isotropic phase to biphasic state and from biphasic state to nematic phase. Observed tactoid aspect ratio R/r as a

• function of tactoid volume Rr2. Filled circle and open circle indicate bipolar tactoid and homogenous tactoid respectively. Dashed line denotes the estimated transition volume from homogenous to bipolar tactoids (=15310 μm3). (a, b) POM images of the DWCNT film at (a) 0° and (b) 45° under crossed

NMRium: Teaching nuclear magnetic resonance spectra interpretation in an online platform

• Luc Patiny,
• Hamed Musallam,
• Alejandro Bolaños,
• Michaël Zasso,
• Julien Wist,
• Metin Karayilan,
• Eva Ziegler,
• Johannes C. Liermann and
• Nils E. Schlörer

Beilstein J. Org. Chem. 2024, 20, 25–31, doi:10.3762/bjoc.20.4

• grasp functionality would make it a preselected tool for the review process of chemistry publications. Future developments of NMRium include the processing of 2D NMR experiments, as well as a CASE- and prediction-supported assignment tool with an integrated validation function for assigned data [44

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• , Supporting Information File 1). Next, we analyzed the function of CmaA6, which was predicted to catalyze the diazotization of 3-aminocoumaric acid (3-ACA, 3) in p-coumaric acid biosynthesis. As expected, 3-diazocoumaric acid (3-DCA, 4) was synthesized by CmaA6 in the presence of ATP and sodium nitrite

Long oligodeoxynucleotides: chemical synthesis, isolation via catching-by-polymerization, verification via sequencing, and gene expression demonstration

• Yipeng Yin,
• Reed Arneson,
• Alexander Apostle,
• Adikari M. D. N. Eriyagama,
• Komal Chillar,
• Emma Burke,
• Martina Jahfetson,
• Yinan Yuan and
• Shiyue Fang

Beilstein J. Org. Chem. 2023, 19, 1957–1965, doi:10.3762/bjoc.19.146

• is usually associated with promiscuous annealing and secondary structures. Problematically, many secondary structures such as hairpin, cruciform, and G-quadruplex are actually needed for genes and genomes to function, and thus these genes and genomes may not be accessible. (4) Genes having long

Beyond n-dopants for organic semiconductors: use of bibenzo[d]imidazoles in UV-promoted dehalogenation reactions of organic halides

• Kan Tang,
• Megan R. Brown,
• Chad Risko,
• Melissa K. Gish,
• Garry Rumbles,
• Phuc H. Pham,
• Oana R. Luca,
• Stephen Barlow and
• Seth R. Marder

Beilstein J. Org. Chem. 2023, 19, 1912–1922, doi:10.3762/bjoc.19.142

• -normalized initial reaction rate (d([RX]/dt)0/[D2]0) as a function of the initial benzyl bromide concentration ([RX]0) obtained from several experiments of the type shown in part (a) for different [D2] and [RX] for both D2 = (Cyc-DMBI)2 and (N-DMBI)2. For these slow reactions, the “initial” rates were

Anion–π catalysis on carbon allotropes

• M. Ángeles Gutiérrez López,
• Mei-Ling Tan,
• Giacomo Renno,
• Augustina Jozeliūnaitė,
• J. Jonathan Nué-Martinez,
• Javier Lopez-Andarias,
• Naomi Sakai and
• Stefan Matile

Beilstein J. Org. Chem. 2023, 19, 1881–1894, doi:10.3762/bjoc.19.140

• to C60 fullerenes [12]. These amines function as bases, their position next to the aromatic surface is essential to turn on anion–π interactions as soon as substrate 4 is deprotonated. Fullerene derivatization with the Bingel reaction installs a cyclopropane that continues with one or two acid

• monomeric fullerenes (22, A/D = 4.6) but weaker than on fullerene dimers (37, A/D = 12.5). The true activity is presumably much higher because MWCNTs, and SWCNTs, are heterogenous catalysts that operate as suspensions with only a minor fraction of the total π surface accessible for function. Fullerene

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• of TOF measurements. The similar situation was in the case of the other compounds which showed current transients without detectable transit times (Figure S7 in Supporting Information File 1). The electron mobility (µe) as the function of the electric field was substantial for 7 with the field

• under a nitrogen atmosphere. TGA allows us to observe the weight changes of the samples as a function of temperature, providing valuable insights into processes such as decomposition, volatilization, and oxidation. In the case of DSC measurements, the samples were heated at a rate of 10 °C/min in a

Controlling the reactivity of La@C₈₂ by reduction: reaction of the La@C₈₂ anion with alkyl halide with high regioselectivity

• Yutaka Maeda,
• Saeka Akita,
• Mitsuaki Suzuki,
• Michio Yamada,
• Takeshi Akasaka,
• Kaoru Kobayashi and
• Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

• crystal has two independent units of 3a and three CS2 molecules as guest solvents. The difference between the two independent units is the direction of the tolyl group in the crystal (Supporting Information File 1, Figure S7). (a) Charge density of La@C2v-C82 anion as a function of its POAV values and (b

• ) an enlarged part view of blue region in (a). (c) Spin density of La@C2v-C82 as a function of its POAV values [34][35]. (d) Molecular structure of La@C2v-C82 and numbering carbon atoms. Reaction of the La@C2v-C82 anion with benzyl bromide derivatives. Charge densities and POAV values of carbon atoms

GlAIcomics: a deep neural network classifier for spectroscopy-augmented mass spectrometric glycans data

• Thomas Barillot,
• Baptiste Schindler,
• Baptiste Moge,
• Elisa Fadda,
• Franck Lépine and
• Isabelle Compagnon

Beilstein J. Org. Chem. 2023, 19, 1825–1831, doi:10.3762/bjoc.19.134

• vibrational resonances as a function of their frequency in the mid-IR range. After measuring its mass and its IR fingerprint, an unknown analyte (Figure 1a) is readily identified as "GlcNAc" (for N-acetylglucosamine) by comparison with the reference IR spectra of several candidates of identical mass (Figure

• ) activation functions for each layer. Two dropout layers are interleaved after the first and second hidden layers with a dropout setting of 25% to avoid over-fitting issues. The training objective is a classification task between the 4 monomer categories with a cross-entropy loss function. To account for the

• , energy shift, and downsampling. The mean accuracy of the model as a function of these four parameters is shown in Figure 4. Note that all parameters have a uniform distribution over the 8000 samples and can be studied independently. The amplitude modulation and downsampling do not play a major role, with

Synthetic approach to 2-alkyl-4-quinolones and 2-alkyl-4-quinolone-3-carboxamides based on common β-keto amide precursors

• Yordanka Mollova-Sapundzhieva,
• Plamen Angelov,
• Danail Georgiev and
• Pavel Yanev

Beilstein J. Org. Chem. 2023, 19, 1804–1810, doi:10.3762/bjoc.19.132

• avicennae [18]. Inhibition of hepatitis C virus replication by 2-nonyl-4-quinolone, isolated from Ruta angustifolia leaves, has also been reported [19]. Another significant group of natural 4-quinolones are those of microbial origin. The function of these compounds in the microbial world is a matter of

• great research interest, with many reviews published in the recent years [20][21][22]. Some of the compounds are known to act as antibiotics [23][24][25][26], while others function as quorum-sensing signal molecules which regulate the production and release of virulence factors in bacteria, thus helping

Charge carrier transport in perylene-based and pyrene-based columnar liquid crystals

• Alessandro L. Alves,
• Simone V. Bernardino,
• Carlos H. Stadtlober,
• Edivandro Girotto,
• Giliandro Farias,
• Rodney M. do Nascimento,
• Sergio F. Curcio,
• Thiago Cazati,
• Marta E. R. Dotto,
• Juliana Eccher,
• Leonardo N. Furini,
• Hugo Gallardo,
• Harald Bock and
• Ivan H. Bechtold

Beilstein J. Org. Chem. 2023, 19, 1755–1765, doi:10.3762/bjoc.19.128

• -shifted in the film. These results indicate molecular π-stacking aggregation and excimer formation on the films [2]. The PL in film was obtained as a function of temperature (Figure 4). The observed reduction of the PL intensity on heating is expected for organic semiconductors due to self-quenching

• the mobility μ(E) at an electric field of 6.0 × 105 V/cm. Figure 7 shows the charge carrier mobility as a function of the applied electric field, calculated from . The electron mobility of 1 is around one order of magnitude lower than that of holes, depending on the electric field. It suggests that

• Optics USB4000 spectrophotometer. The PL spectra were collected with a Hitachi fluorescence spectrophotometer (Model F-7000) and the samples were excited at the wavelength of maximal absorption. For the PL as a function of the temperature, casting films were placed on a hot stage (Mettler Toledo FP-82

Effects of the aldehyde-derived ring substituent on the properties of two new bioinspired trimethoxybenzoylhydrazones: methyl vs nitro groups

• Dayanne Martins,
• Roberta Lamosa,
• Talis Uelisson da Silva,
• Carolina B. P. Ligiero,
• Sérgio de Paula Machado,
• Daphne S. Cukierman and
• Nicolás A. Rey

Beilstein J. Org. Chem. 2023, 19, 1713–1727, doi:10.3762/bjoc.19.125

• registering the UV–vis spectra of a series of hdz-NO2 10% DMSO/buffer (acetate, phosphate or Tris-HCl) solutions with different pH values, ranging from 3.8 to 8.2 (Figure 7A). By plotting the absorbance at λmax as a function of pH and then fitting the curve with a sigmoidal function (Figure 7A, inset), an

Quinoxaline derivatives as attractive electron-transporting materials

• Zeeshan Abid,
• Liaqat Ali,
• Sughra Gulzar,
• Faiza Wahad,
• Raja Shahid Ashraf and
• Christian B. Nielsen

Beilstein J. Org. Chem. 2023, 19, 1694–1712, doi:10.3762/bjoc.19.124

• self-assembled monolayer in devices. The molecular dipole and work function of gold was adjusted by using fluorine and CN as well as dimethylamino substituents on the quinoxaline. Notably, the researchers tuned the work function of gold over a range of 1.0 eV [59]. The study by You et al. quoted in the

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• , the molecule contains both the intrinsic LE and CT excited states or demonstrates HLCT characteristics. Besides, the Stokes shifts between absorption and emission spectra were plotted as a function of solvent polarity function (Δf) corresponding to the Lipper–Mataga model which defines the

• electron-only MIS device and 15 μs and −5 V for the hole-only MIS device, respectively, and their MIS-CELIV signal transient plots as a function of time are shown in Figure 6c and 6d. As the applied voltage increased, it was found that the transient peak shifted to slightly shorter times indicating an

• increasing carrier mobility. The hole and electron mobilities (μ) were calculated and plotted as a function of electric field (E1/2). As illustrated in Figure 6b, the mobility (μ) of both holes and electrons is electric field dependent and gradually increases on increasing the electric field, which is

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• over 19% used a BHJ of PM6:BTP-eC9 with PFN-Br as the CIL [6]. CILs serve to increase device performance in various ways. First, polar functional groups (and induced dipole moments) serve to tune the work function of the cathode for a reduced energetic offset, thus reducing the Schottky barrier that is

• and acceptor molecules (N···F and N···H bonding when using the acceptor Y6), as well as an induced dipole moment in the molecule for increased work function tuning of the cathode. The use of benzyl and pentafluorobenzyl substituents was to evaluate the impact of H vs F on the electrochemical

• [19]. The energy level diagram of each respective layer in the device are represented in Figure 5c, where PEDOT:PSS, PM6, and Y6 work function and energy levels were taken from literature [17][30]. We evaluated the current density–voltage (J–V) in the dark and under illumination (AM1.5 G at 100 mW/cm2

Complexes of resorcin[4]arene with secondary amines: synthesis, solvent influence on “in-out” structure, and theoretical calculations of non-covalent interactions

• Waldemar Iwanek

Beilstein J. Org. Chem. 2023, 19, 1525–1536, doi:10.3762/bjoc.19.109

• procedure: Optimization of the R[4]A and sec-amine geometries was performed with the GFN2-xTB method using the ALPB solvent model with the “veryTight” accuracy using the xTB software package [29]. Complex assembly search (aISS) was performed using the “dock” function with “tight” optimization of the

Functions of enzyme domains in 2-methylisoborneol biosynthesis and enzymatic synthesis of non-natural analogs

• Binbin Gu,
• Lin-Fu Liang and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2023, 19, 1452–1459, doi:10.3762/bjoc.19.104

• studied. Several 2-methylisoborneol synthases have a proline-rich N-terminal domain of unknown function. The results presented here demonstrate that this domain leads to a reduced enzyme activity, in addition to its ability to increase long-term solubility of the protein. Furthermore, the substrate scope

• versions of 2MIBSs exhibit a proline-rich N-terminal domain of unknown function that appears disordered in the crystal structure [28]. As a first aspect of this study, we have investigated the possible function of this N-terminal domain. 2MIBS is known to form several methylated monoterpenes as side

• changed alkylation pattern. Results and Discussion Function of the proline-rich N-terminal domain of 2MIBS S. coelicolor 2MIBS was selected to investigate the function of the proline-rich N-terminal domain (hereafter termed A domain, the C-terminal domain is named as domain B). Based on a sequence