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Frustrated Lewis pairs (FLPs) have been the subject of considerable study since the field's inception. While much of the research into FLPs has centered around small molecule activation for diverse stoichiometric and catalytic transformations, intramolecular FLPs also show promise as chelating ligands. The cooperative action of Lewis basic and acidic moieties enables intramolecular FLPs to stabilize low oxidation state centers and (consequently) reactive molecular fragments through a donor‐acceptor approach, making them an attractive ligand class in main group element chemistry. This review outlines the state of FLP chelation to date throughout the p‐block, encompassing primarily groups 13–16. [ABSTRACT FROM AUTHOR]

Wearable healthcare systems have captured the interest of researchers because they enable smarter and more personalized healthcare. However, these systems are limited by a separation between biosensors and therapeutic units that results in interrupted treatment and compromised patient recovery. It is therefore imperative to develop wearable closed‐loop medical devices that fully integrate physiological/pathological monitoring, signal feedback detection, diagnostics, and on‐demand therapeutic administration. Such systems require safe, sustainable, and continuously operating power sources, and bioenergy has gained attention in this regard because it can be sourced continuously from the human body without requiring substantial rigid energy storage space. The effective utilization of bioenergy would enable the realization of a self‐driven closed‐loop medical system with treatment‐monitoring feedback. [ABSTRACT FROM AUTHOR]

Benzamide‐derived organochalcogens (chalcogen=S, Se, and Te) have shown promising interest in biological and synthetic chemistry. Ebselen molecule derived from benzamide moiety is the most studied organoselenium. However, its heavier congener organotellurium is under‐explored. Here, an efficient copper‐catalyzed atom economical synthetic method has been developed to synthesize 2‐phenyl‐benzamide tellurenyl iodides by inserting a tellurium atom into carbon‐iodine bond of 2‐iodobenzamides in one pot with 78–95 % yields. Further, the Lewis acidic nature of Te center and Lewis basic nature of nitrogen of the synthesized 2‐Iodo‐N‐(quinolin‐8‐yl)benzamide tellurenyl iodides enabled them as pre‐catalyst for the activation of epoxide with CO2 at 1 atm for the preparation of cyclic carbonates with TOF and TON values of 1447 h−1 and 4343, respectively, under solvent‐free conditions. In addition, 2‐iodo‐N‐(quinolin‐8‐yl)benzamide tellurenyl iodides have also been used as pre‐catalyst for activating anilines and CO2 to form a variety of 1,3‐diaryl ureas up to 95 % yield. The mechanistic investigation for CO2 mitigation is done by 125Te NMR and HRMS studies. It seems that the reaction proceeds via formation of catalytically active Te−N heterocycle, an ebtellur intermediate which is isolated and structurally characterized. [ABSTRACT FROM AUTHOR]

The heterocyclic tetrazole, a well‐established bioisosteric replacement of carboxylic acid, plays an important role in medicinal chemistry. To deepen the functional understanding of tetrazoles in chemical sciences, it is essential to investigate the noncovalent interactions between the tetrazole ring and aromatic rings. Here, we report synthetic, spectroscopic, structural and quantum chemical analyses on specially designed 2‐arylphenyl‐1H‐tetrazoles to study the underlying noncovalent interactions between the tetrazole ring and the neighboring aromatic ring possessing substituents at para/meta position. pKa values and proton affinities of 2‐arylphenyl‐1H‐tetrazoles correlate well with Hammett sigma values of para‐substituents at the flanking aromatic ring. Molecular orbital and energy decomposition analyses reveal that through‐space NH–π interactions and π–π interactions contribute to the trend of pKa values and proton affinities of 2‐arylphenyl‐1H‐tetrazoles. The electrostatic interaction between tetrazole/tetrazolide interacting with the aromatic rings appears responsible for the observed acidity trends. These results will be helpful for the rational design of tetrazole‐based drugs and materials. [ABSTRACT FROM AUTHOR]

The synergistic regulation of the multi-functional sites on one receptor molecule with different cationic effectors for anion recognition is scarce to be well understood from the experiment and theory. In this work, a new anion receptor with three functional zones including ether hole, biurea and double bipyridine groups (EUPR) is designed expecting to enhance the chloride anion recognition together with a rational synthesis path being proposed based on four simple and mature organic reaction steps. The conformational structures of the designed receptor EUPR and the binding behaviors for three kinds of ions (Cl - , Na + , and Ag + ) are deeply investigated by using density functional theoretical calculations. It is found that Cl - binding via the hydrogen bond interaction can be significantly enhanced and synergistically regulated by the two kinds of cations and the corresponding conformational changes of receptor EUPR. Especially, the conformational pre-organization of receptor caused by the encapsulation of sodium ion into ether hole is benefit to the binding for Cl - in both thermodynamics and kinetics. Na + binding, in turn, can ever be enhanced by chloride anion, whereas it seems that Ag + binding cannot always be enhanced by chloride anion, reflecting an electrical complementary matching and mutual enhancement effect for different counter ions. Moreover, solvent effect calculations indicate that EUPR may be an ideal candidate structure for Cl - recognition by strategy of counter ion enhancement in water. Additionally, a visual study of intermolecular noncovalent interaction (NCI) and molecular electrostatic potential (ESP) are used for the analysis on the nature of interactions between receptor and bound ions., (© 2024 Wiley Periodicals LLC.)

Introduction: Cancer poses a significant public health challenge in both developed and developing nations, with a rising global incidence of patients facing the threat of death due to abnormal cell proliferation., Aim: Review explores the utilization of different parts of herbal medicinal plants and their active pharmaceutical constituents in the prevention and treatment of various types of cancer., Methodology: Various anticancer medicinal plants have been identified, demonstrating their therapeutic effects by inhibiting cancer-stimulating enzymes and hormones, activating DNA repair processes, boosting the synthesis of protective stimulants, reducing the formation of free radicals, and enhancing individual immunity. Data for this study were gathered from diverse online bibliographic and databases, including Google, Google Scholar, Mendeley, Springer Link, Research Gate, and PubMed., Result: Herbal drugs have a huge contribution to the inhibition of the progression of cancer.A large volume of clinical studies has reported the beneficial effects of herbal medicines on the survival, immune modulation, and quality of life (QOL) of cancer patients, when these herbal medicines are used in combination with conventional therapeutics., Conclusion: The latest medicines for the clinical purpose (Above 50 %) are derived from herbal products. Furthermore, combination of these herbs with nanotechnology shows promise in treating specific carcinomas., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

A novel solvent‐free energetic coordination polymer [Ag(3,4‐dnp)] was performed by dehydration. The structure was confirmed by single‐crystal X‐ray crystallography and the Ag(I) ions are coordinated in bidentate‐bridging mode. The results of thermal analysis (thermogravimetric and accelerating rate calorimeter) show that this compound has higher thermal stability than that of the traditional CHON‐containing energetic materials, RDX, HMX and CL‐20. The detonation velocity and detonation pressure of [Ag(3,4‐dnp)] are 5.532 km s−1, 15.88 GPa, respectively, which is lower than that HMX, RDX and TNT, and comparable with the 2D MOFs [Ag(Mtta)] based on the Ag ions and 5‐methyl tetrazole. The impact and friction sensitivities of this compound are infinitely close to RDX, state‐of‐the‐art explosive. The coordination polymers based on metal ions and nitropyrazole are promising potential as energetic materials. [ABSTRACT FROM AUTHOR]

Frustrated Lewis pairs (FLPs) have been the subject of considerable study since the field's inception. While much of the research into FLPs has centered around small molecule activation for diverse stoichiometric and catalytic transformations, intramolecular FLPs also show promise as chelating ligands. The cooperative action of Lewis basic and acidic moieties enables intramolecular FLPs to stabilize low oxidation state centers and (consequently) reactive molecular fragments through a donor-acceptor approach, making them an attractive ligand class in main group element chemistry. This review outlines the state of FLP chelation to date throughout the p-block, encompassing primarily groups 13-16., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

A classical methodology to design free‐base meso‐tetra‐(1‐pyrenyl)porphyrin (H2TPyrP) and their corresponding metalloporphyrins containing Zn(II), Cu(II), Ni(II), Co(III), and Mn(III) was described. These porphyrins were characterized in terms of structure, photophysical, and interactions profile with calf‐thymus deoxyribonucleic acid (CT‐DNA) and bovine serum albumin (BSA). H2TPyrP exhibited five characteristic bands in the visible wavelength: Soret (432 nm) and Q‐bands (520–650 nm range), while the metalloporphyrins showed some spectrum shifts according to the nature of the ion, which were also explored by time‐dependent density functional theory (TD‐DFT) calculations. The fluorescence and singlet oxygen quantum yield (Φfl, ΦΔ, respectively) decreased with the presence of metal species in the porphyrin core. The porphyrins interact spontaneously via a ground‐state association in the minor groove of CT‐DNA following the increasing order of binding: CuTPyrP

In contrast to p‐quinodimethane tetraesters, which undergo facile polymerization due to their diradical character, newly synthesized 1 and 2 consisting of a chalcogenadiazole fused to a p‐naphthoquinodimethane tetraester are thermodynamically stable due to butterfly‐shaped deformation. Such a folded molecular structure is also favorable for chalcogen bond (ChB) formation through intermolecular close contacts between a chalcogen atom (E: Se or S) and the oxygen atoms of ester groups in a crystal. The less‐explored chelating‐ChB through a C=O⋅⋅⋅E⋅⋅⋅O=C contact [Se⋅⋅⋅O: 2.94–3.37 Å] is the key supramolecular synthon for the formation of a one‐dimensional rod‐like assembly in a crystal, which is commonly observed in selenadiazole‐tetraesters (1) with OMe, OEt, and OiPr groups. The formation of inclusion cavities between the rods shows that 1 could serve as solid‐state host molecules for clathrate formation, as found in a hexane‐solvated crystal. In contrast, thiadiazole‐tetraesters (2) are less suitable for the formation of a rod‐like assembly since the ChB involving S is less effective, and thus is overwhelmed by weak hydrogen bonds through C−H⋅⋅⋅O contacts. [ABSTRACT FROM AUTHOR]

Over the last few years, organic bioelectronics has experienced an exponential growth with applications encompassing platforms for tissue engineering, drug delivery systems, implantable, and wearable sensors. Although reducing the physical and mechanical mismatch with the human tissues allows to increase the coupling efficiency, several challenges are still open in terms of matching biological curvature, size, and interface stiffness. In this context, the replacement of bulky with more flexible and conformable devices is required, implying the transition from inorganic conventional electronics to organic electronics. Indeed, the advent of organic materials in bioelectronics, due to the indisputable benefits related to biocompatibility, flexibility, and electrical properties, has granted superior coupling properties with human tissues increasing the performances of both sensing and stimulation platforms. In this review the ease of functionalization and patterning of conductive polymers (CPs) will be analyzed as a strategy that enables the fabrication of platforms with high structural flexibility ranging from the macro to the micro/nano‐scales, leading to the increase of devices sensitivity. Drawing from the concept of biomimicry, the human body tissues interfaces will be explored through an ideal journey starting from organic platforms for epidermal sensing and stimulation. Then, devices capable of establishing a dynamic coupling with the heart will be reviewed and finally, following the circulatory system and crossing the blood‐brain barrier, the brain will be reached and novel sensing and computing implants advances that pave the way to the possibility to emulate as well as to interact with the neural functions will be analyzed. [ABSTRACT FROM AUTHOR]

Chromatographic exploration of methanol extract derived from Saussurea lappa roots yielded four sesquiterpene lactones, santamarin (1), dehydrocostuslactone (2), costunolide (3) and zaluzanin C (4) along with the well‐known triterpene, β‐sitosterol (5). Chemical structures were determined based on extensive 1D/2D NMR analyses. In antiviral assay, compounds 1–5 showed % antiviral activity ranging from 2.18±3.1 to 53.7±10.05 % and from 15.39±4.83 to 92.91±2.47 % when tested against hepatitis A virus (HAV) and Herpes simplex virus type 1 (HSV‐1), respectively. Molecular docking simulation studies against (HSV‐1) DNA polymerase and (HAV) 3 C proteinase enzymes showed similar binding interactions as for acyclovir. Compounds (1 and 3–5) showed moderate to potent antibacterial activity against Bacillus subtilis ATCC 6633 (MIC values between 7.9 and 31.25 μg/ml) whereas, dehydrocostuslactone (2) and costunolide (3) exhibited comparable antibacterial activities against Pseudomonas aeruginosa ATCC 90274 (MIC values=125 μg/ml) compared to gentamicin as a positive control. In cytotoxicity assay against human colorectal carcinoma (HCT‐116) and human epithelioid cervical carcinoma (HeLa), compounds 1 and 4 exhibited weak to moderate activities. Compound 1 showed IC50 values of 46.05 μg/ml (185.44 μM) and 59.38 μg/ml (239.1153 μM) whereas compound 4 showed IC50 values of 36.08 μg/ml (146.48 μM) and 46.59 μg/ml (189.175 μM), respectively. [ABSTRACT FROM AUTHOR]

Benzamide-derived organochalcogens (chalcogen=S, Se, and Te) have shown promising interest in biological and synthetic chemistry. Ebselen molecule derived from benzamide moiety is the most studied organoselenium. However, its heavier congener organotellurium is under-explored. Here, an efficient copper-catalyzed atom economical synthetic method has been developed to synthesize 2-phenyl-benzamide tellurenyl iodides by inserting a tellurium atom into carbon-iodine bond of 2-iodobenzamides in one pot with 78-95 % yields. Further, the Lewis acidic nature of Te center and Lewis basic nature of nitrogen of the synthesized 2-Iodo-N-(quinolin-8-yl)benzamide tellurenyl iodides enabled them as pre-catalyst for the activation of epoxide with CO 2 at 1 atm for the preparation of cyclic carbonates with TOF and TON values of 1447 h -1 and 4343, respectively, under solvent-free conditions. In addition, 2-iodo-N-(quinolin-8-yl)benzamide tellurenyl iodides have also been used as pre-catalyst for activating anilines and CO 2 to form a variety of 1,3-diaryl ureas up to 95 % yield. The mechanistic investigation for CO 2 mitigation is done by 125 Te NMR and HRMS studies. It seems that the reaction proceeds via formation of catalytically active Te-N heterocycle, an ebtellur intermediate which is isolated and structurally characterized., (© 2023 Wiley-VCH GmbH.)

The heterocyclic tetrazole, a well-established bioisosteric replacement of carboxylic acid, plays an important role in medicinal chemistry. To deepen the functional understanding of tetrazoles in chemical sciences, it is essential to investigate the noncovalent interactions between the tetrazole ring and aromatic rings. Here, we report synthetic, spectroscopic, structural and quantum chemical analyses on specially designed 2-arylphenyl-1H-tetrazoles to study the underlying noncovalent interactions between the tetrazole ring and the neighboring aromatic ring possessing substituents at para/meta position. pK a values and proton affinities of 2-arylphenyl-1H-tetrazoles correlate well with Hammett sigma values of para-substituents at the flanking aromatic ring. Molecular orbital and energy decomposition analyses reveal that through-space NH-π interactions and π-π interactions contribute to the trend of pK a values and proton affinities of 2-arylphenyl-1H-tetrazoles. The electrostatic interaction between tetrazole/tetrazolide interacting with the aromatic rings appears responsible for the observed acidity trends. These results will be helpful for the rational design of tetrazole-based drugs and materials., (© 2023 The Authors. Chemistry - An Asian Journal published by Wiley-VCH GmbH.)