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191.
The crystal structures of fac‐(acetonitrile‐κN)(2‐{[3,5‐bis(4‐methoxyphenyl)‐2H‐pyrrol‐2‐ylidene‐κN1]amino}‐3,5‐bis(4‐<!?tlsb=0.2pt>methoxyphenyl)‐1H‐pyrrol‐1‐ido‐κN1)tricarbonylrhenium(I)–hexane–acetonitrile (2/1/2), [Re(C36H30N3O4)(CH3CN)(CO)3]·0.5C6H14·CH3CN, (2), and fac‐(2‐{[3,5‐bis(4‐methoxyphenyl)‐2H‐pyrrol‐2‐ylidene‐κN1]amino}‐3,5‐bis(4‐methoxyphenyl)‐1H‐pyrrol‐1‐ido‐κN1)tricarbonyl(dimethyl sulfoxide‐κO)rhenium(I), [Re(C36H30N3O4)(C2H6OS)(CO)3], (3), at 150 K are reported. Both complexes display a distorted octahedral geometry, with a fac‐Re(CO)3 arrangement and one azadipyrromethene (ADPM) chelating ligand in the equatorial position. One solvent molecule completes the coordination sphere of the ReI centre in the remaining axial position. The ADPM ligand shows high flexibility upon coordination, while retaining its π‐delocalized nature. Bond length and angle analyses indicate that the differences in the geometry around the ReI centre in (2) and (3), and those found in three reported fac‐Re(CO)3–ADPM complexes, are dictated mainly by steric factors and crystal packing. Both structures display intramolecular C—H...N hydrogen bonding. Intermolecular interactions of the Csp2—H...π and Csp2—H...O(carbonyl) types link the discrete monomers into extended chains.  相似文献   
192.
193.
This work describes the synthesis and anticancer activity against kinase enzymes of newly designed thiophene and thieno[2,3-d]pyrimidine derivatives, along with their potential to activate autophagic and apoptotic cell death in cancer cells. The designed compounds were scanned for their affinity for kinases. The results were promising with affinity ranges from 46.7% to 13.3%. Molecular docking studies were performed, and the compounds were then screened for their antiproliferative effects. Interestingly, compounds 8 and 5 resulted in higher cytotoxic effects than the reference standard against MCF-7 and HepG-2. The compounds were evaluated for their induction of apoptosis and/or necrosis on HT-29 and HepG-2. Three compounds induced significant early apoptosis compared to untreated control HT-29 cells, and four derivatives were more significant compared to untreated HepG-2 cells. We further investigated the effect of four compounds on the autophagy process within HT-29, HepG-2, and MCF-7 cells with flow cytometry. Similar to the apoptosis results, compound 5 showed the highest autophagic induction among all compounds. The potential inhibitory activity of the synthesized compounds on kinases was assessed. Screened compounds showed inhibition activity ranging from 41.4% to 83.5%. Compounds recorded significant inhibition were further investigated for their specific FLT3 kinase inhibitory activity. Noticeably, Compound 5 exhibited the highest inhibitory activity against FLT3.  相似文献   
194.
Novel 1,2,3-triazolo-linked-1,5-benzodiazepinones were designed and synthesized via a Cu(I)-catalyzed 1,3-dipolar alkyne-azide coupling reaction (CuAAC). The chemical structures of these compounds were confirmed by 1H NMR, 13C NMR, HMBC, HRMS, and elemental analysis. The compounds were screened for their in vitro antibacterial and antifungal activities. Several compounds exhibited good to moderate activities compared to those of established standard drugs. Furthermore, the binding interactions of these active analogs were confirmed through molecular docking.  相似文献   
195.
This paper presents the one‐pot reaction synthesis of coordination calcium and strontium compounds [Ca(L)2(H2O)2 1 and Sr(L)2(H2O)2 2 ] with the 2‐(4‐chlorophenylamino) benzoic acid ligand ( HL  = C13H10NO2Cl). The complexes were obtained in good yields, and their structures were corroborated according to their CHN, spectroscopic (IR and UV/Vis.) and solution molar conductivity data as the latter confirmed their molecular nature. Additionally, the powder X‐ray diffraction pattern of the complexes was used to determine the cell parameters and the hkl indices together with their corresponding 2θ values. The microbial resistance against the currently available antifungal agents requires searching for new antifungal compounds. Promising fungicidal activities of these coordination complexes were determined against the Fusarium corn disease as complexes 1 and 2 at 30°C inhibited the grain pathogenicity by 70% and 66%, respectively. Moreover, 1 and 2 retarded the amylase enzymes that are responsible for the pathogenicity by 35.13% and 26.22% at 30°C.  相似文献   
196.
Because of energy crisis, the hydrogen evolution reaction (HER) limits the feasible utilization of water splitting. Herein, we report reduced graphene-oxide (rGO) with Iron-oxide (Fe3O4) nanostructures as highly active electrocatalyst for HER. As-prepared [email protected]3O4 shows superior electrochemical responses to those of corresponding its monometallic rGO and Fe3O4. The overpotential of [email protected]3O4 has been achieved as 300 mV at 10 mA/cm2 current density with a Tafel slope of 80 mV/dec. The [email protected]3O4 nanostructure has its stability for 24 h to reveal long term electrochemical performance.  相似文献   
197.
The pyrrolidinium hydrogen sulfate (PHS) was used as an excellent ionic liquid catalyst for the preparation of many imidazoles moiety, which have biologically application via one-pot multicomponent reaction. Imidazoles were afforded through the reaction of equimolar from 1,2-diphenylethane-1,2-dione, ammonium acetate, different aromatic aldehydes, and ethyl glycinate hydrochloride. This method has the advantages of giving excellent yield, shortened reaction times, and ease of establishment. Moreover, the yielded of imidazoles components can be purified and crystallized by a nonchromatographic technique, and the catalyst can be reused. These entire novel synthesized components have been identified by spectral data: IR, NMR and mass spectra. These compounds have an in vivo antioxidant activity on experimental animals (rats).  相似文献   
198.
Let {φi}i=0 be a sequence of orthonormal polynomials on the unit circle with respect to a positive Borel measure μ that is symmetric with respect to conjugation. We study asymptotic behavior of the expected number of real zeros, say En(μ), of random polynomials
Pn(z):=i=0nηiφi(z),
where η0,,ηn are i.i.d. standard Gaussian random variables. When μ is the acrlength measure such polynomials are called Kac polynomials and it was shown by Wilkins that En(|dξ|) admits an asymptotic expansion of the form
En(|dξ|)2πlog?(n+1)+p=0Ap(n+1)?p
(Kac himself obtained the leading term of this expansion). In this work we generalize the result of Wilkins to the case where μ is absolutely continuous with respect to arclength measure and its Radon–Nikodym derivative extends to a holomorphic non-vanishing function in some neighborhood of the unit circle. In this case En(μ) admits an analogous expansion with the coefficients Ap depending on the measure μ for p1 (the leading order term and A0 remain the same).  相似文献   
199.
Research on Chemical Intermediates - Increased carbon dioxide (CO2) emissions from anthropogenic activities are a contributing factor to the growing global warming worldwide. The economical method...  相似文献   
200.
For the first time, alpha‐fetoprotein (AFP) quantification as an early test for liver cancer diagnosis competing with other interfering analytes and factors based on a novel nano‐magnetic metal–organic framework (MOF) was investigated. The novel nano‐magnetic MOF was synthesized via a simple preparation method, and characterized using various techniques. The X‐ray photoelectron spectrum of the nano‐magnetic MOF shows Cu 2p, O 1s, N 1s and C 1s peaks that evidence the presence of these elements in the sample without any impurities. Scanning and transmission electron microscopy images show the nano‐magnetic MOF with average size between 22 and 43 nm. The results of a photoluminescence study show that the nano‐magnetic MOF exhibits strong emission at 418 nm after excitation at 354 nm. Moreover, a Stern–Völmer graph shows a linear calibration curve over an AFP concentration range 1.0–520 ng ml?1 with a correlation coefficient of 0.997, detection limit of 1.18 ng ml?1 and quantitation limit of 3.58 ng ml?1. According to the marked quenching of the photoluminescence intensity of the nano‐magnetic MOF using various concentrations of AFP, it was successfully used as a biosensor for AFP in serum samples collected from hepatitis patients in addition to healthy males and females. The quenching mechanism was well studied, and found to be a dynamic type. The present work offers a simple, low‐cost, room‐temperature and rapid technique, being non‐time‐consuming, highly accurate, selective and highly sensitive compared with most published methods.  相似文献   
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