Hole‐Transporting Materials with Rational Combination of Pyridine and Dibenzo[a,c]phenazine as Electron Acceptor for Dopant‐Free Perovskite Solar Cells†

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Hole-Transporting Materials with Rational Combination of Pyridine and Dibenzo[a,c]phenazine as Electron Acceptor for Dopant-Free Perovskite Solar Cells†

Based on rational combination of dibenzo[a,c]phenazine and pyridine as electronic acceptor and anchoring groups to perovskite layer, DPyP as a hole-transporting material in dopant-free PSC achieved high conversion efficiency of 20.45%, higher than that of DBP (19.77%) based on dibenzo[a,c]phenazine.


Comprehensive Summary

Perovskite solar cells (PSCs) have been proven to be a promising option for photovoltaic conversion. With the aim to achieve efficient and stable PSCs, it is essential to explore dopant-free hole-transporting materials (HTMs) with high hole mobility. Herein, HTMs bearing electron donor (D)-electron acceptor (A)-electron donor (D) structures have been constructed with strong intramolecular charge transfer (ICT) effect, based on rational combination of dibenzo[a,c]phenazine and pyridine as electronic acceptors and anchoring groups to perovskite layer. Accordingly, high hole mobility (7.31 × 10–5 cm2·V–1·s–1) and photoelectric conversion efficiency (20.45%) have been achieved by dopant-free DPyP-based PSC. It afforded an efficient way to design HTMs with high hole mobility by adjustment of molecular configurations and electronic property of conjugated systems.

New quinoxaline‐piperazine‐oxazole conjugates: Synthesis, in vitro anticancer, in silico ADMET, and molecular docking studies

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New quinoxaline-piperazine-oxazole conjugates: Synthesis, in vitro anticancer, in silico ADMET, and molecular docking studies

Herein, we described the synthesis of some new phthalazine piperazine-pyrazole conjugates(6a-n) and their in vitro anticancer activity against four human cancer cell lines such as PC-3, MCF-7, DU-145, and A-549. The anticancer activity results reveals that the four compounds 6c, 6h, 6i, and 6n shown promising activity than the standard drug Erlotinib. Furthermore, the in silico studies of compounds 6c, 6h, 6i, and 6n supports the in vitro anticancer results. In addition, ADMET analyses were carried out on four potent compounds and results accordant with the in vitro anticancer and in vitro EGFR tyrosine kinase inhibition data.


Abstract

In this paper, we describe the synthesis of some new quinoxaline-piperazine-oxazole amide conjugates 6a-n from 3-chloroquinoxaline-2-carbonitrile using well-known reaction sequences. The synthesized compounds were characterized by 1H NMR,13C NMR, and mass spectral analysis. The compounds were tested for their in vitro antiproliferative activity toward four different cancer cell lines such as PC-3, MCF-7, DU-145, and A-549 by MTT method. The compounds, 6c, 6h, 6i, and 6n were found to be more potent than the standard Erlotinib. In vitro tyrosine kinase EGFR inhibition studies using four potent compounds revealed that 6n has double inhibiting tendency with value IC50 of 0.22 μM and 6h with value of IC50 0.27 μM compared to reference compound. Molecular docking studies of active compounds, 6c, 6h, 6i, and 6n on EGFR receptor suggested that all the compounds have more binding energies than that of Erlotinib. Furthermore, the in silico pharmacokinetic profile was accomplished for the active compounds, 6c, 6h, 6i, and 6n using SWISS/ADME and pk CSM, whereas compounds, 6h, 6i, and 6c followed Lipinski rule, Veber rule, Egan rule and Muegge rule. The remaining compound 6n did not follow Lipinski rule, Ghose rule because one common violation, that is, because of high molecular weight (MW > 350).

Converting Conventional Host to TADF Sensitizer and Hot‐Exciton Emitter in Donor‐Adamantane‐Acceptor Triads for Blue OLEDs: A Computational Study

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Converting Conventional Host to TADF Sensitizer and Hot-Exciton Emitter in Donor-Adamantane-Acceptor Triads for Blue OLEDs: A Computational Study

TADF Sensitizer and Hot-Exciton Emitter: The conventional host molecule undergoes a conversion into a TADF sensitizer and a Hot-Exciton emitter via distinct donor and acceptor unit substitutions on the adamantane core. Molecules incorporating acceptor units such as DMB and BODIPY, which feature boron atoms, have the potential to serve as TADF sensitizers and Hot-exciton emitters for OLED applications, respectively.


Abstract

Exploiting triplet excitons in TADF sensitizers and hot-exciton emitters has attracted considerable attention and interest in recent studies on the design and development of blue OLEDs. The structural and optical property relationship of adamantane (Ad) core appended with four different strengths of donor and seven acceptor units were investigated using DFT and TD-DFT methods. The theoretical studies revealed that increased donor and acceptor strength on adamantane building block leads to: (i) a decrease in ionization potentials and an increase in electron affinities, (ii) a decrease in singlet energies (ES) and the S1-T1 energy gaps (ΔEST); (iii) decreased SOC magnitudes between S1-T1 states; (iv) increased RISC rate from the Tn to S1 states, demonstrating an increased tendency for upconversion of triplet excitons from the Tn to S1 state. In addition, low exchange energy causes excited state characteristics of molecules to shift from HLCT to CT nature in the S1 state. In contrast, the T1 states retain their LE character, resulting in higher triplet energies (ET). The adamantane molecular systems appended with P-DMAC-Donor-Ad-P-DMB and Donor-Ad-P-BODIPY based triads exhibit promising TADF sensitizer and hot-exciton characteristics to find application as potential candidates for blue OLEDs when compared to experimentally reported conventional host.

Synthesis of compounds based on the active domain of cabotegravir and their application in inhibiting tumor cells activity

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Synthesis of compounds based on the active domain of cabotegravir and their application in inhibiting tumor cells activity

The objective of this study was to assess the inhibitory effect of modified cabotegravir derivatives on the activity of esophageal cancer KYSE30 cells. Results showed that compounds 5b and 5h effectively inhibited the migration and invasion of KYSE30 cells and induced apoptosis and may be involved in the stat3 and smad2/3 signal pathway. Based on these findings, we can consider these compounds as potential lead candidates for the treatment of esophageal squamous cell carcinoma.


Abstract

Structural modification based on existing drugs, which ensures the safety of marketed drugs, is an essential approach in developing new drugs. In this study, we modified the structure of cabotegravir by introducing the front alkyne on the core structure through chemical reaction, resulting in the synthesis of 9 compounds resembling 1,2,3-triazoles. The potential of these new cabotegravir derivatives as tumor suppressors in gastrointestinal tumors was investigated. Based on the MTT experiment, most compounds showed a reduction in the viability of KYSE30 and HCT116 cells. Notably, derivatives 5b and 5h exhibited the most significant inhibitory effects. To further explore the effects of derivatives 5b and 5h on gastrointestinal tumors, KYSE30 cells were chosen as a representative cell line. Both derivatives can effectively curtail the migration and invasion capabilities of KYSE30 cells and induce apoptosis in a dose-dependent manner. We further demonstrated these derivatives induce cell apoptosis in KYSE30 cells by inhibiting the expression of Stat3 protein and Smad2/3 protein. Based on the above results, we suggest they show promise in developing drugs for esophageal squamous cell carcinoma.

Characterization of the Binding Properties of Ten Aptamers Using the Intrinsic Fluorescence of Oxytetracycline

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Characterization of the Binding Properties of Ten Aptamers Using the Intrinsic Fluorescence of Oxytetracycline

Taking advantage of the intrinsic fluorescence of oxytetracycline, its binding to ten different DNA aptamers was characterized using fluorescence quantum yield, binding kinetics, fluorescence lifetime and calorimetry, offering insights into aptamer binding to small molecules.


Abstract

Tetracyclines are a class of commonly used four-ringed antibiotics. A series of DNA aptamers were recently obtained using the capture-SELEX (systematic evolution of ligands by exponential enrichment) method to bind to oxytetracycline, and one of the aptamers can bind to a few other tetracycline antibiotics as well. Upon binding to the aptamers, the intrinsic fluorescence of tetracycline antibiotics can be enhanced. At least 10 different DNA aptamers were isolated from the previous selection experiment. In this work, a systematic characterization of these ten aptamers was performed. Each of these aptamers shows a different degree of fluorescence enhancement ranging from around 1-fold to over 20-fold. Fluorescence enhancement was boosted in the presence of Mg2+. Isothermal titration calorimetry (ITC) studies were done and showed a great variety in dissociation constant (K d) from 62 nM to 1.6 μM. Steady-state fluorescence spectroscopy and fluorescence lifetime studies showed a correlation between fluorescence lifetime and degree of fluorescence enhancement. A few aptamers showed slow binding kinetics, although no correlation was found between the kinetics of fluorescence change and degree of fluorescence enhancement. This is the first study of ten different aptamers for the same target, providing fundamental insights into aptamer binding and bioanalytical applications.

Catalytic combustion of toluene performance over MnOx catalysts: Effect of KMnO4 content

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Catalytic combustion of toluene performance over MnOx catalysts: Effect of KMnO4 content

MnO x with different KMnO4 contents was synthesized by a simple hydrothermal method. The appearance of mixed phases, multiple structural defects, and higher Mn3+/(Mn3+ + Mn4+) and O latt /(O ads  + O latt ) concentrations promoted the emergence-annihilation cycle of oxygen vacancies, which facilitated the catalytic combustion reaction of toluene. The reaction pathway was investigated using the in situ DRIFT method, which the benzoic acid was main intermediate of toluene degradation.


MnO x samples were prepared and applied to the catalytic combustion of toluene. The results indicated that the KMnO4 content was important to the catalytic performance. Cat-0.2 (0.2 g KMnO4) possessed the best catalytic performance, and more than 90% of toluene conversion was 255°C. Moderate amounts of KMnO4 facilitated the generation of mixed crystalline phases and structural defects, which led to the generation of more oxygen vacancies. In addition, the Cat-0.2 possessed high contents of O ads /(O ads  + O latt ) and Mn3+/(Mn3+ + Mn4+), which promoted the emergence-annihilation cycle of oxygen vacancies and facilitated the reaction process of toluene. The reaction pathway of toluene was investigated via in situ DRIFTS, in which the by-products included benzyl alcohol, benzaldehyde, benzoate, maleic anhydride, and short-chain carbonate. Among them, benzoate was the main intermediate in the catalytic oxidation process of toluene.

Mixed‐Valence Manganese Carboxylate Clusters, {MnIII6MnII4}, {MnIII7MnII5Na}, and {MnIII7MnII5}, Derived from the Combined Use of Di‐2‐pyridyl Ketone with Selected Aliphatic Diols

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Mixed-Valence Manganese Carboxylate Clusters, {MnIII6MnII4}, {MnIII7MnII5Na}, and {MnIII7MnII5}, Derived from the Combined Use of Di-2-pyridyl Ketone with Selected Aliphatic Diols

The combined use of di-2-pyridyl ketone with the aliphatic diols 1,3-propanediol (pdH2) or 1,4-butanediol (1,4-bdH2) in manganese carboxylate chemistry has afforded three new polynuclear clusters with the {MnIII 6MnII 4} and {MnIII 7MnII 5} nuclearities. The compounds feature unique multilayer cores, not previously observed in manganese cluster chemistry, and possess interesting magnetic properties.


Abstract

Three new polynuclear clusters with the formulae [Mn10O4(OH)(OMe){(py)2C(O)2}2{(py)2C(OMe)(O)}4(MeCO2)6](ClO4)2 (1), Na[Mn12O2(OH)3(OMe){(py)2C(O)2}6{(py)2C(OH)(O)}2(MeCO2)2(H2O)10](ClO4)8 (2) and [Mn12O4(OH)2{(py)2C(O)2}6{(py)2C(OMe)(O)}(MeCO2)3(NO3)3(H2O)(DMF)2](NO3)2 (3) were prepared from the combination of di-2-pyridyl ketone, (py)2CO, with the aliphatic diols (1,3-propanediol (pdH2) or 1,4-butanediol (1,4-bdH2)) in Mn carboxylate chemistry. The reported compounds do not include the aliphatic diols employed in this reaction scheme; however, their use is essential for the formation of 1–3. The crystal structures of 1–3 are based on multilayer cores which, to our knowledge, are reported for the first time in Mn cluster chemistry. Direct current (dc) magnetic susceptibility studies showed the presence of dominant antiferromagnetic exchange interactions within 1–3. Alternating current (ac) magnetic susceptibility studies revealed the presence of out-of-phase signals below 3.0 K for 2 and 3 indicating the slow relaxation of the magnetization vector, characteristic of single-molecule magnets; the Ueff value of 2 was found to be 23 K and the preexponential factor τ0 ~7.6×10−9 s.

Phosphate Triester Hydrolysis by Mononuclear Iron(III) Complexes: the Role of Benzimidazole in the Second Coordination Sphere

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Phosphate Triester Hydrolysis by Mononuclear Iron(III) Complexes: the Role of Benzimidazole in the Second Coordination Sphere

This research addresses the scarcity of examples in phosphate triester hydrolysis by introducing three mononuclear iron(III) complexes. Notably, complexes 2 and 3, featuring benzimidazole moieties, demonstrated strategic variations in aliphatic chain lengths, influencing catalytic activity. Structural analyses, including spectrophotometry and DFT modelling, revealed their high-spin nature and distorted octahedral geometries. Catalytic experiments showed a significant (27 times) enhancement in hydrolysis rates for diethyl-2,4-dinitrophenylphosphate, highlighting the potential of these complexes as efficient catalysts for agrochemical degradation.


Abstract

Over the years, phosphate ester hydrolysis catalyzed by coordination compounds has attracted extensive research on developing new bioinspired compounds. However, the literature lacks sufficient examples displaying activity toward phosphate triesters specifically, limiting the understanding of efficient strategies for the hydrolysis of this compound hydrolysis. Herein, we report preparing and characterizing three mononuclear iron(III) complexes (1, 2, and 3) and their hydrolase-like activity. Complexes 2 and 3 have benzimidazole (BIMZ) moieties and were strategically designed to separate the BIMZ moiety from the first coordination sphere, and complex 1 (without BIMZ) was used as a reference. Several techniques provided structural information, including spectrophotometry, spectrometry, electrochemistry, elemental analysis, and 57Fe Mossbauer. Density functional theory (DFT) revealed distorted octahedral geometries due to the presence of the BIMZ groups. These groups also directly affected the protonation equilibria and catalytic activity. The phosphate triester diethyl-2,4-dinitrophenylphosphate (DEDNPP) hydrolysis was enhanced at least 27 times compared to the uncatalyzed reaction, with complexes 2 and 3, thus showing higher catalytic rates (k cat). Moreover, a longer carbon chain led to a higher hydrolysis rate but less interaction with substrate. These findings provide background for further investigations and the development of efficient catalysts for agrochemical degradation.

Spectroscopic Study on the Complexation of trivalent Actinide and Lanthanide ions with TEDGA in Solution

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Spectroscopic Study on the Complexation of trivalent Actinide and Lanthanide ions with TEDGA in Solution

By using NMR spectroscopy, this study provides novel insights into the M(III)-TEDGA interaction in [M(TEDGA)3]3+ complexes (M=Ln, Am). The chemical shift analyses solidify the assumption of almost identical metal-ligand interaction between Am(III)−O and Ln(III)−O.


Abstract

NMR spectroscopy studies on the complexation of La(III), Sm(III), Lu(III), Y(III) and Am(III) with N,N,N′,N′-tetraethyldiglycolamide (TEDGA) have been performed. Initial studies concerning the stoichiometry of the complexes prove the formation of [M(TEDGA)3]3+ in D2O and [M(TEDGA)1-3]3+ in CD3CN. Decreasing the solvent polarity translates to an increase of the complex stability as shown by complementary TRLFS studies with Cm(III). Due to delocalization of the lone electron pair of the amide nitrogen atom, the M(III)−O interaction has been studied indirectly by collecting 13C and 15N NMR data. The observed chemical shifts prove that the interaction of the trivalent ions, An(III) and Ln(III), and TEDGA is almost identical.

Protein Glycosylation Patterns Shaped By the IRE1‐XBP1s Arm of the Unfolded Protein Response

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Protein Glycosylation Patterns Shaped By the IRE1-XBP1s Arm of the Unfolded Protein Response


Abstract

The unfolded protein response (UPR) is a sensing and signaling pathway that surveys the endoplasmic reticulum (ER) for protein folding challenges and responds whenever issues are detected. UPR activation leads to upregulation of secretory pathway chaperones and quality control factors, as well as reduces the nascent protein load on the ER, thereby restoring and maintaining proteostasis. This paradigm-defining view of the role of the UPR is accurate, but it elides additional key functions of the UPR in cell biology. In particular, recent work has revealed that the UPR can shape the structure and function of N- and O-glycans installed on ER client proteins. This crosstalk between the UPR's reaction to protein misfolding and the regulation of glycosylation remains insufficiently understood. Still, emerging evidence makes it clear that the UPR, and particularly the IRE1-XBP1s arm of the UPR, may be a central regulator of protein glycosylation, with important biological consequences. In this review, we discuss the crosstalk between proteostasis, the UPR, and glycosylation, present progress towards understanding biological functions of this crosstalk, and examine potential roles in diseases such as cancer.