Chemistry – An Asian Journal
ISSN / EISSN : 1861-4728 / 1861-471X
Published by: Wiley-Blackwell (10.1002)
Total articles ≅ 6,439
Latest articles in this journal
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100917
Half-sandwich Ru II complexes, [(YZ)Ru II (η 6 -arene)(X)]+, (YZ= chelating bidentate ligand, X = halide), with N , N and N , O coordination ( 1-9 ) show significant antiproliferative activity against the metastatic triple negative breast carcinoma (MDA-MB-231). 3-aminobenzoic acid or its methyl ester is used in all the ligands while varying the aldehyde for N , N and N , O coordination. In the N,N coordinated complex the coordinated halide(X) is varied for enhancing stability in solution (X = Cl, I). Rapid aquation and halide exchange of the pyridine analogues, 2 and 3 , in solution are a major bane towards their antiproliferative activity. Presence of free -COOH group ( 1 and 4) make complexes hydrophilic and reduces toxicity. The imidazolyl 3-aminobenzoate based N,N coordinated 5 and 6 display better solution stability and efficient antiproliferative activity (IC 50 ca. 2.3-2.5 µM) compared to the pyridine based 2 and 3 (IC 50 > 100 µM) or the N,O coordinated complexes ( 7 - 9 ) (IC 50 ca. 7-10 µM). The iodido coordinated, 6 , is resistant towards aquation and halide exchange. The N,O coordinated 7 - 9 underwent instantaneous aquation at pH 7.4 generating monoaquated complexes stable for at least 6 h. Complexes 5 and 6 , bind to 9-ethylguanine (9-EtG) showing propensity to interact with DNA bases. The complexes may kill via apoptosis as displayed from the study of 8 . The change in coordination mode and the aldehyde affected the solution stability, antiproliferative activity and mechanistic pathways. The N,N coordinated ( 5 , 6 ) exhibit arrest in the G2/M phase while the N,O coordinated 8 , showed arrest in the G0/G1 phase.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100896
Interleukin-33 (IL-33) is an epithelial-derived cytokine that plays an important role in immune-mediated diseases such as asthma, atopic dermatitis, and rheumatoid arthritis. Although IL-33 is considered a potential target for the treatment of allergy-related diseases, no small molecule that inhibits IL-33 has been reported. Based on the structure-activity relationship and in vitro 2D NMR studies employing 15 N-labeled IL-33, we identified that the oxazolo[4,5- c ]-quinolinone analog 7c binds to the interface region of IL-33 and IL-33 receptor (ST2), an orphan receptor of the IL-1 receptor family. Compound 7c effectively inhibited the production of IL-6 in human mast cells in a dose-dependent manner. Compound 7c is the first low molecular weight IL-33 inhibitor and may be used as a prototype molecule for structural optimization and investigation of the IL-33/ST2 signaling pathway.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100972
D -fructose, a biomass-derived carbohydrate has been identified as an environmentally benign C2 synthon in the preparation of synthetically useful 2-hydroxymethylbenzimidazole derivatives by coupling with 1,2 phenylenediamines. The proof of concept was established by synthesizing 23 examples using BF3.OEt2 (20 mol %), TBHP (5.5 M, decane) (1.0 equiv.) in CH3CN at 90 oC for 1 h. The pivotal features of this method include metal-free conditions, short time, good functional group tolerance, gram scale feasibility and the synthesis of benzimidazole fused 1,4-oxazine. Control studies with conventional C2 synthons did not produce the desired product suggesting a new reaction pathway from D-fructose.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100984
The enantioselectivity in the propargylic substitution reactions of propargylic alcohols with acetone catalyzed by optically active thiolate-bridged diruthenium complexes was examined via ωB97X-D level DFT calculations. Some structures with intramolecular dispersion interactions between ligands were found for the ruthenium-allenylidene complex, which is the key intermediate in the catalytic reaction, and it was determined that the structure corresponding to the X-ray crystal structure, which had provided the transition state model for the enantioselectivity in previous studies, was not the most stable among the obtained structures. Then, a variety of transition-state structures for the nucleophilic attack of prop-1-ene-2-ol, which is the enol isomer of acetone, on the γ-carbon of the ruthenium-allenylidene complex were explored. Among the transition-state structures with lower energies, the number of structures leading to the major ( R ) product was found to be larger than that of structures leading to the minor ( S ) product, providing enantioselectivity in terms of probability distributions. The introduction of a phenyl group in the thiolate ligand was suggested to increase the selectivity. Thus, we propose the novel transition state model for the asymmetric catalytic reaction system.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100909
Covalent organic frameworks (COFs) are promising materials for membrane separation thanks to their adjustable topological structures and surface properties of nanopores. Herein, a melamine (Me) doped COF membrane was fabricated by chemically doping the melamine monomer into TpPa COF, which is formed by the condensation reaction between the 1,3,5-triformylphloroglucinol (Tp) and p-phenylenediamine (Pa) monomers via interfacial polymerization . The introduction of melamine monomer allows altering both the pore structure and pore surface of the TpPa COF membrane, leading to enhanced hydrogen purification performance. Specifically, the separation factor of H 2 /CO 2 gas mixture by using the melamine doped TpPa COF (TpPaMe COF) membrane reaches 12.7, with hydrogen permeance of 727 GPU, in sharp contrast to the relatively low separation factor and gas permeance of 7.5 and 618 GPU of the undoped TpPa membrane. Besides, the TpPaMe COF membrane shows good running stability, with H 2 /CO 2 separation performance well surpasses the Robeson 2008 upper bound.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100963
Bismuth-based compounds possess layered structures with a variety of stacking modes, endowing the compounds with diverse properties. As one type of bismuth oxysulfides, Bi 9O7.5S6 nanocrystals has great applications in photodetection; however, the responsivity of bulky Bi 9O7.5S6 is limited due to the poor charge separation. Herein, single-crystalline Bi 9O7.5S6 thin nanosheets are successfully synthesized by using a solvothermal method. The thickness of the obtained Bi 9O7.5S6 nanosheets is down to 15 nm and can be easily tuned by varying the reaction period. Moreover, the Bi 9O7.5S6 nanosheets show strong light absorption in the visible and near infrared range, making it a promising candidate in optoelectronics. As a demonstration, the thin Bi 9O7.5S6 nanosheets are used as active layer in an optoelectronic device, which exhibits sensitive photoelectric response to light in a wide range of 400-800 nm. The responsivity of the device reaches up to 1140 μA W−1, and the performance of the device is stable after long-period illumination. This work demonstrates a great potential of the thin Bi 9O7.5S6 nanosheets in optoelectronic devices, and these nanosheets may also be extended to various optoelectronic applications.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100810
Transition metal phosphides (TMPs) as ever-evolving electrocatalytic materials have attracted increasing attention in water splitting reaction owing to their cost-effective, highly active and stable catalytic properties. This work presents a facile synthetic route to NiCoP nanoparticles with Ru dopants which function as highly efficient electrocatalysts for oxygen evolution reaction (OER) in alkaline media. The Ru dopants induced a high content of Ni and Co vacancies in NiCoP nanoparticles, and the more defective Ru doped NiCoP phase than undoped NiCoP ones led to a greater number of catalytically active sites and improved electrical conductivity after undergoing electrochemical activation. The Ru doped NiCoP catalyst exhibited high OER catalytic performance in alkaline media with a low overpotential of 281 mV at 10 mA cm -2 and a Tafel slope of 42.7 mV dec -1 .
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100922
Process intensification, targeting the maximization of spatial-temporal productivity utilizing minimum energy and resources has always been the constant trends especially in chemical industry. In this regard, tandem reactions that are able to perform a multi-step reaction in a single pot by eliminating costly separation steps have been viewed as a typical paradigm. However, a spatial isolation of varied active sites with a controlled manner in a single catalyst to avoid deactivation and work synergistically is a challenging problem yet sometimes being overlooked. In this work, a spatial base-metal core-shell structured catalyst with wrinkled surface was successfully fabricated by a direct homoepitaxial growth method in an acid/water system, which exhibited increased hydrophobicity, exposure of active sites and significantly improved product selectivity towards one-pot Knoevenagel condensation-hydrogenation tandem reaction compared with the uncoated catalyst. Meanwhile, the catalytic performance was largely retained and the structural stability was maintained even after successive 8 cycles, which shows great promise for industrial applications.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100957
Catalysis is one of the key techniques for people’s modern life. It has created numerous essential chemicals such as biomedicines, agricultural chemicals and unique materials. Heterogeneous catalysis is the new emerging method with reusable catalysts. Among heterogenous catalysis patterns developed so far, single crystalline catalysis has become the promising one owing to its high catalytic density and selectivity resulted by the inherent porosity, orderliness of the lattices and permeability. These crystalline catalysts could be used in various reactions such as photo-dimerization, Diels-Alder reaction, CO 2 transformation and so on. In this review, we highlighted the reported works about the single crystalline catalysts. Both discrete small molecules and metal-organic frameworks (MOFs) have been used to prepare single crystals for catalysis. For discrete molecules based crystalline catalysts, coordinated and covalent molecules have been used. There were more catalytic modes in crystalline MOF catalysts. Three patterns were identified in this review: single crystalline MOFs i) without catalytic sites, ii) with inherent catalytic features and iii) with introducing catalytic units by post synthetic modification. Based on these examples, this review committed to provide the inspirations for the further design and application of single crystalline materials.
Chemistry – An Asian Journal; https://doi.org/10.1002/asia.202100985
In this paper, two D-π-D type compounds, C1 and C2, containing dihydrodinaphthopentacene (DHDNP) as a π-bridge, p-methoxydiphenylamine and p-methoxytriphenylamine groups as the donor groups were synthesized. The four 4-hexylphenyl groups at the sp3-carbon bridges of DHDNP were acquainted with control morphology and improving solubility. The light absorption, energy level, thermal properties, and application as hole-transporting materials in perovskite solar cells of these compounds were fully investigated. The HOMO/LUMO levels and energy gaps of these DHDNP-based molecules are suitable for use as hole-transporting materials in PSCs. The best power conversion efficiencies of the PVSCs based on the C1 and C2 are 15.96% and 12.86%, respectively. The performance of C1 is comparable to that of the reference compound spiro-OMeTAD (16.38%). Compared with spiro-OMeTAD, the C1-based PVSC device showed good stability, which was slightly decreased to 98.68% of its initial efficiency after 48h and retained 81% of its original PCE after 334h without encapsulation. These results reveal the potential usefulness of the DHDNP building block for further development of economical and highly efficient HTMs for PVSCs.