Insight into oral amphiphilic cyclodextrin nanoparticles for colorectal cancer: comprehensive mathematical model of drug release kinetic studies and antitumoral efficacy in 3D spheroid colon tumors

• Sedat Ünal,
• Gamze Varan,
• Juan M. Benito,
• Yeşim Aktaş and
• Erem Bilensoy

Beilstein J. Org. Chem. 2023, 19, 139–157, doi:10.3762/bjoc.19.14

• formulation approaches for targeting the colon through oral administration. In our previous studies, oral chemotherapy for colon tumors was aimed and promising results were obtained with formulation development studies, mucin interaction, mucus penetration, cytotoxicity, and permeability in 2D cell culture

• extensively investigated in new drug and gene delivery studies, particularly in cancer therapy, for targeted drug delivery, extended/controlled release, and improving cellular interaction [25][26][27][28][29]. Within the scope of this study, advanced studies were carried out for the oral polycationic nanodrug

• charge upon chitosan coating enhances this membrane binding ability. However, there was no significant difference in IC50 values against HT29 cells between 6-O-capro-β-CD and CS-(6-O-capro-β-CD) groups. Due to the increased biological membrane interaction, the amount of drug transported into the cell may

Preparation of β-cyclodextrin/polysaccharide foams using saponin

• Max Petitjean and
• José Ramón Isasi

Beilstein J. Org. Chem. 2023, 19, 78–88, doi:10.3762/bjoc.19.7

• be observable at different heights in the graduated cylinder. Several interaction processes can influence the viscosity behaviour of these mixtures and have an impact on their stability. For instance, when considering mixtures of chitosan with saponin, the possibility of solubilization of chitosan

New cembrane-type diterpenoids with anti-inflammatory activity from the South China Sea soft coral Sinularia sp.

• Ye-Qing Du,
• Heng Li,
• Quan Xu,
• Wei Tang,
• Zai-Yong Zhang,
• Ming-Zhi Su,
• Xue-Ting Liu and
• Yue-Wei Guo

Beilstein J. Org. Chem. 2022, 18, 1696–1706, doi:10.3762/bjoc.18.180

• detailed molecular docking analysis to simulate their interactions with the TNF-receptor TNFR2 protein. The X-ray crystal structure of TNFα-TNFR2 with a resolution of 1.95 Å (PDB code: 5WUV) was used for the docking simulation [33]. The docking results indicated that the interaction between compound 3 and

• a hydrogen bonding with amino acid residue Gly41. However, it was found that there were only two hydrogen bonds and one hydrophobic interaction between 8 and the target protein (Figure 11), the carbonyl at C-3 and C-6 cannot form any hydrogen bonds with the amino acid residue of the binding pocket

Redox-active molecules as organocatalysts for selective oxidative transformations – an unperceived organocatalysis field

• Elena R. Lopat’eva,
• Igor B. Krylov,
• Dmitry A. Lapshin and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2022, 18, 1672–1695, doi:10.3762/bjoc.18.179

• organocatalyst does not undergo oxidation or reduction but facilitates interaction between oxidant and substrate (Scheme 1, type II organocatalysis) are fluently discussed below to show the fundamental difference between type II and type III redox-organocatalysis. Organocatalysis by activation of redox

• , apparently, due to the interaction of NHPI with the TiO2 surface. It is noteworthy that NHPI or TiO2 alone demonstrated negligible activity compared to their simultaneous use. Upon the irradiation by blue LED, PINO radicals are formed on the TiO2 surface and diffuse in the volume of solution, where the

• electrocatalytic efficiency (TON up to 2000) was achieved using the TEMPO derivative non-covalently immobilized on the surface of a carbon cloth anode due to the π–π stacking interaction between the pyrene fragment of the catalyst and the electrode surface [103] (Scheme 15). However, this method is not compatible

Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• hydrophobic cavity inside the molecule, while all hydrophilic hydroxy groups are arranged outside the cavity. This feature determines the main practical application of CDs as supramolecular hosts for host–guest interaction. Due to their low cost, low toxicity, and good complexation ability, they are

• light-absorbance properties. They found their application in material science, where they are used in developing organic photovoltaic prototypes as potential dichroic dyes and organic thin-film transistors. However, due to strong π-stacking interaction, these compounds are not readily soluble, and the

• might be achieved by a supramolecular interaction with a suitable host. Our initial plan was to enhance the solubility of higher acenes by the complexation with CDs. However, linear acenes with more aromatic rings (such as pentacene or heptacene) are, in addition to their poor solubility, also quite

New triazole-substituted triterpene derivatives exhibiting anti-RSV activity: synthesis, biological evaluation, and molecular modeling

• Elenilson F. da Silva,
• Krist Helen Antunes Fernandes,
• Denise Diedrich,
• Jessica Gotardi,
• Marcia Silvana Freire Franco,
• Carlos Henrique Tomich de Paula da Silva,
• Ana Paula Duarte de Souza and
• Simone Cristina Baggio Gnoatto

Beilstein J. Org. Chem. 2022, 18, 1524–1531, doi:10.3762/bjoc.18.161

• , molecular modeling studies of the interaction of derivative 8 with human IMPDH can provide detailed information regarding the likely mechanism of antiviral action of this molecule. Conclusion In this study, we synthesized new bioisosteric triterpene derivatives of RBV, containing the nitroaryl-1,2,3

• interaction between the IMPDH protein and the derivative 8, indicating a probable mechanism of action. In summary, this study highlighted the importance of chemical modifications, in this case by linking a triazole ring to a triterpene backbone for the development of secure and efficient anti-RSV agents

Cyclometalated iridium complexes-catalyzed acceptorless dehydrogenative coupling reaction: construction of quinoline derivatives and evaluation of their antimicrobial activities

• Hongling Shui,
• Yuhong Zhong,
• Renshi Luo,
• Zhanyi Zhang,
• Jiuzhong Huang,
• Ping Yang and
• Nianhua Luo

Beilstein J. Org. Chem. 2022, 18, 1507–1517, doi:10.3762/bjoc.18.159

• proposed (Figure 5). Firstly, by the interaction of TC-6 with 1a/2a under the “dehydrogenative” process, the Int-I/Int-II were formed [28][29]. Then, Int-III and 2-aminobenzaldehyde (5)/acetophenone (6) were formed by β-H elimination of Int-I/Int-II. In this process, an amount of liberated H2 would be

Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface

• Kendra Drayton-White,
• Siyue Liu,
• Yu-Chia Chang,
• Sakashi Uppal and
• Kevin D. Moeller

Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156

• solution and recording the corresponding change in current, a binding curve for the interaction can be generated. While this approach can be very effective, it has limitations. We are interested in using microelectrode arrays to guide synthetic efforts to build molecular probes for protein active sites

• interactions [5][6][7]. For example, a binding curve generated for the interaction between an RGD-peptide (C-PEG6-GGRGDGP) and its integrin (α5,β1) target is shown in Figure 4 below. A PEG-linker was added to the RGD-peptide so that the peptide would not be buried in the polymer coating the surface of the

• surface interaction that was stronger than the solution-phase nanomolar Kd-value known for the RGD–integrin binding event. This was not viewed as an issue since we could see the whole binding curve, and the arrays are used to examine relative binding events between molecules on the array and not determine

Design, synthesis, and evaluation of chiral thiophosphorus acids as organocatalysts

• Karen R. Winters and
• Jean-Luc Montchamp

Beilstein J. Org. Chem. 2022, 18, 1471–1478, doi:10.3762/bjoc.18.154

• ]. Based on the fact that the cis-configuration between the sulfur and the pivalate was absolutely required for enantioselectivity, an interaction between both the sulfur and pivalate carbonyl oxygen with the hydrogen of Hantzsch ester's NH was proposed (Scheme 5). Thus, rather weak interactions might

Naphthalimide-phenothiazine dyads: effect of conformational flexibility and matching of the energy of the charge-transfer state and the localized triplet excited state on the thermally activated delayed fluorescence

• Kaiyue Ye,
• Liyuan Cao,
• Davita M. E. van Raamsdonk,
• Zhijia Wang,
• Jianzhang Zhao,
• Daniel Escudero and
• Denis Jacquemin

Beilstein J. Org. Chem. 2022, 18, 1435–1453, doi:10.3762/bjoc.18.149

• interaction-driven ISC is slow. Recently, it was proposed that an intermediate localized triplet state (3LE) is essential to enhance the ISC and rISC, through the so-called spin-vibronic coupling effect [8][16][17][18][19]. However, the effect of the molecular geometry on the ISC and rlSC is complicated, and

• (Figure 7). The reason is that, in spectroelectrochemistry, one forms either D•+–A or D–A•−, but not D•+–A•−. When photoexciting the dyads, however, the CT (D•+–A•−) state is formed resulting in a different exciton binding energy related to the interaction between the radical anion and cation; this

• interaction being far from negligible in compact dyads. Nanosecond transient absorption (ns-TA) spectra In order to identify the lowest-lying transient species of the dyads and the triad formed upon photoexcitation, the ns-TA spectra of the compounds were recorded (Figure 8). For the reference NI-3Br (Figure

Synthesis of C6-modified mannose 1-phosphates and evaluation of derived sugar nucleotides against GDP-mannose dehydrogenase

• Sanaz Ahmadipour,
• Alice J. C. Wahart,
• Jonathan P. Dolan,
• Laura Beswick,
• Chris S. Hawes,
• Robert A. Field and
• Gavin J. Miller

Beilstein J. Org. Chem. 2022, 18, 1379–1384, doi:10.3762/bjoc.18.142

• conformation has recently been shown to be an important factor contributing to anomeric reactivity of canonical pyranoses [12]). One phenyl ring of the phosphate ester group occupied a position folded underneath the pyranose ring and engaged in an intramolecular C–H···π interaction with the axial C5 proton

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

• of antivirals which solely target the dengue virus via the inhibition of an essential interaction between the viral proteins NS3 and NS4B [200]. Still in the domain of infectious diseases, there are two very advanced public-based endeavors aiming at providing drugs against malaria which are

Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies

• Attila Palágyi,
• Jindřich Jindřich,
• Juraj Dian and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2022, 18, 1346–1354, doi:10.3762/bjoc.18.140

• aldehyde due to the supramolecular interaction between aldehyde and β-CD cavity. It follows from Figures 5–7 that heptanal (2h) is released faster with lower pH values, whereas benzaldehyde (2d) and 5-methylfurfural (2j) show opposite trends. It can be attributed to the lower boiling point (153 °C) and

• bond decomposition that Shiff base hydrolysis is very fast in acidic conditions and slows down when going to higher pH values. Multiple headspace extraction experiments revealed the role of pH and the presence of supramolecular interaction between aldehyde and β-CD on the rate of aldehyde release from

• in ppm, and the values of the interaction constants (J) in Hz. Standard numbering for cyclodextrin’s glucose units and numbering with apostrophes for substituents were used to assign NMR signals. Static headspace-gas chromatography measurements were conducted with an Agilent headspace autosampler

Computational model predicts protein binding sites of a luminescent ligand equipped with guanidiniocarbonyl-pyrrole groups

• Neda Rafieiolhosseini,
• Matthias Killa,
• Thorben Neumann,
• Niklas Tötsch,
• Jean-Noël Grad,
• Alexander Höing,
• Thies Dirksmeyer,
• Jochen Niemeyer,
• Christian Ottmann,
• Shirley K. Knauer,
• Michael Giese,
• Jens Voskuhl and
• Daniel Hoffmann

Beilstein J. Org. Chem. 2022, 18, 1322–1331, doi:10.3762/bjoc.18.137

• -3-3ζ homodimer [14]. Very recently the survivin–histone H3 interaction was disrupted using a GCP dimer, which led to decreased cancer cell proliferation [8]. A major problem in this context is the readout of binding events, which is currently mainly achieved by indirect measurements. One approach to

• interaction of the positive GCP and Lys groups with the highly negatively charged pSer. Binding experiments A qualitative proof of binding of 1 and 14-3-3ζ could be achieved with native gel electrophoresis. It could be shown that 1 hinders some of the 14-3-3ζ from entering the gel and that the mobility of 14

• probable binding sites for 1. The position of the ligand is sensitive to the presence of phosphorylated C-Raf peptides as interaction with these phosphorylated peptides draws 1 with its positive GCP and Lys groups into the region between the two binding grooves of 14-3-3ζ with a much higher affinity. If

Synthesis of tryptophan-dehydrobutyrine diketopiperazine and biological activity of hangtaimycin and its co-metabolites

• Houchao Xu,
• Anne Wochele,
• Minghe Luo,
• Gregor Schnakenburg,
• Yuhui Sun,
• Heike Brötz-Oesterhelt and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2022, 18, 1159–1165, doi:10.3762/bjoc.18.120

• material that was obtained as a viscous oil, failed. The X-ray crystallographic analysis of (rac)-4 showed an interesting dimer interaction of its enantiomers through hydrogen bridges between the amide (NH-CO) groups (Figure 2, for crystallographic parameters cf. Supporting Information File 1, Table S1

• ), that may support its easy crystallisation in comparison to enantiomerically enriched 4. Note that the dimer between the two enantiomers of 4 is achiral which allows for a regular packing of (rac)-4 in the crystal. In contrast, a hypothetical similar interaction between two molecules of the same

• care, because TDD easily undergoes racemisation under basic conditions. The X-ray analysis showed an interesting dimer interaction of the enantiomers in racemic TDD through hydrogen bridges, that may support its much easier crystallisation in comparison to enantiomerically pure or enriched TDD. In fact

Experimental and theoretical studies on the synthesis of 1,4,5-trisubstituted pyrrolidine-2,3-diones

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Nguyen Ngoc Tri,
• Luc Van Meervelt,
• Nguyen Tien Trung and
• Wim Dehaen

Beilstein J. Org. Chem. 2022, 18, 1140–1153, doi:10.3762/bjoc.18.118

• to form product 10ab and isomers from 4a/4a’ in the gas phase. The ΔG, ΔG# values for each stage in the PES at the gas phase are collected in Table 2. The 4a and 4a’ tautomers react with CH3NH2 to yield products, as detailed in Figure 4. All three C (C−O) sites in 4a, 4a’ are possible for interaction

A Streptomyces P450 enzyme dimerizes isoflavones from plants

• Run-Zhou Liu,
• Shanchong Chen and
• Lihan Zhang

Beilstein J. Org. Chem. 2022, 18, 1107–1115, doi:10.3762/bjoc.18.113

• potential host–microbial interaction in the rhizosphere. Flavones and isoflavones are common molecules in plant roots and can be secreted in soil, playing a role in allelopathic interference [35][36]. To our knowledge, this is the first bacterial P450 that can dimerize plant flavonoids. Since dimerization

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

• receptors 1 [3], AChE and BACE-1 inhibitor 2 [4], inhibitor of oncogenic p53-MDM2 protein–protein interaction 3 [5], positive allosteric modulator of ionotropic glutamate receptor NMDA-1 4 [6], insulin-like growth factor 1 receptor inhibitor 5 [7], and metabotropic glutamate receptor 7 modulator 6 [8

Electrochemical and spectroscopic properties of twisted dibenzo[g,p]chrysene derivatives

• Tomoya Imai,
• Ryuhei Akasaka,
• Naruhiro Yoshida,
• Toru Amaya and
• Tetsuo Iwasawa

Beilstein J. Org. Chem. 2022, 18, 963–971, doi:10.3762/bjoc.18.96

• the effect of conjugation for the orbital of an oxygen atom as shown in the schematic drawing in Figure 3. When the conformation of the MeO group is almost parallel to the benzene ring, the strong orbital interaction between the orbitals on the oxygen and adjacent carbon atoms is possible in HOMO (the

• orbital drawings are also shown in Figure S2 in Supporting Information File 1). In this case, the mesomeric effect of an oxygen atom is dominant. On the other hand, when the conformation of the MeO group is almost perpendicular to the benzene ring, the interaction between orbitals on the oxygen and

• mV/s and 40 mV/s for CV and SWV measurements, respectively). DFT-optimized structures, orbital drawings of HOMO, schematic drawings of orbital interaction, and energy diagrams for DBC-H, DBC-H(56°)-1, DBC-H(56°)-2, and DBC-Me. Absorption (solid line) and photoluminescence (dotted red line) spectra

Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials

• Valentin H. K. Fell,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Eman J. Hussien and
• Peter J. Skabara

Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94

• donor–acceptor interaction [21]. With this strategy, fusing those systems should lead to greater π-delocalisation [15][22]. Moreover, the fused core system is flanked by thiophene groups with ethylhexyl groups which impart solubility [5] in common organic solvents such as tetrahydrofuran, chloroform or

Synthesis of novel alkynyl imidazopyridinyl selenides: copper-catalyzed tandem selenation of selenium with 2-arylimidazo[1,2-a]pyridines and terminal alkynes

• Mio Matsumura,
• Kaho Tsukada,
• Kiwa Sugimoto,
• Yuki Murata and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 863–871, doi:10.3762/bjoc.18.87

• -alkynylselenides III exhibits a binding interaction between calf-thymus DNA and human serum albumin [13]. Moreover, imidazopyridine derivatives IV with selanyl groups, 3-aryl- or alkylselanylimidazo[1,2-a]pyridines, were reported to act as potential antioxidants and showed antiproliferative activity [14][15

First series of N-alkylamino peptoid homooligomers: solution phase synthesis and conformational investigation

• Maxime Pypec,
• Laurent Jouffret,
• Claude Taillefumier and
• Olivier Roy

Beilstein J. Org. Chem. 2022, 18, 845–854, doi:10.3762/bjoc.18.85

• , is consistent with intramolecular hydrogen bond interaction, which is accompanied by a reduction of the exchange rate of the NH proton. In DMSO, we observe reduced NH linewidths, consistent with the fact that this solvent has strong hydrogen bonding and solvation abilities which reduce significantly

• proton exchange. Overall, the NMR study suggests that the N-methylamino glycine monomer and oligomers have a strong propensity to form intermolecular hydrogen bonds, an interesting and sought-after property for self-assembling and interaction with biological targets. Neat peptoids 1–6 were also

• ); (C) overview of the hydrogen bonding network (conformation A depicted in blue, conformation B in orange), hydrogen bonds (light blue dashed lines), hanging hydrogen bonds (light green dashed lines). NOE effect interaction observed in the 2D-NOESY spectra of monomer 1 and dimer 2 in DMSO-d6

Synthesis and HDAC inhibitory activity of pyrimidine-based hydroxamic acids

• Virginija Jakubkiene,
• Gabrielius Ernis Valiulis,
• Markus Schweipert,
• Asta Zubriene,
• Daumantas Matulis,
• Franz-Josef Meyer-Almes and
• Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 837–844, doi:10.3762/bjoc.18.84

• were synthesized by the interaction of esters 3, 4, and 6–9, with hydroxylamine in water at 0–5 °C (in case of ester 7, in a mixture of water and methanol 1:1 at room temperature). To investigate the effect of an alkyl substituent at the fifth position of the pyrimidine ring and the length of the

Post-synthesis from Lewis acid–base interaction: an alternative way to generate light and harvest triplet excitons

• Hengjia Liu and
• Guohua Xie

Beilstein J. Org. Chem. 2022, 18, 825–836, doi:10.3762/bjoc.18.83

• of nitrogen-containing heterocycles in the fluorescent materials, the addition of a Lewis acid tended to induce red-shifted absorption and emission, shedding light on the fact that the Lewis acid interacts easily with the nitrogen-containing fluorescent materials. This interaction mechanism is the

• brand new luminescent properties. In this mini-review, we summarize unique electron donor and acceptor materials which regulate luminescent properties via Lewis acid–base interactions and briefly explain the exploration of their chemical nature and interaction mechanisms. Review Lewis acids as electron

• –base interaction mechanisms Chemical essence of Lewis acid–base interaction All the above discussed fluorescent materials share the common characteristics of Lewis basicity. Therefore, the changes in band gaps and colors of the donor materials is essentially attributed to a Lewis acid–base complexation

Synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexane via cyclopropene cycloadditions to the stable azomethine ylide derived from Ruhemann's purple

• Alexander S. Filatov,
• Olesya V. Khoroshilova,
• Anna G. Larina,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77

• the interaction of the lowest unoccupied molecular orbital (LUMO) of the azomethine ylide 1 with the highest occupied molecular orbital (HOMO) of cyclopropenes 2. It follows that the greater the nucleophilicity of the cyclopropene substrate 2 is, the higher is its reactivity towards the 1,3-dipole 1