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63.
A novel series of diaryl urea derivatives bearing sulfonamide moiety have been designed and synthesized.Their in vitro antitumor effect against human cancer cell lines MX-1,A375,HepG2,Ketr3 and HT-29 was screened and evaluated by the standard MTT assay with sorafenib as the positive control.Some of the compounds showed significant inhibitory activity against multiple cell lines compared to sorafenib.In particular,2,6-dimethyl-4-{6-[3-(4-chloro-3-(trifluoromethyl)phenyl)urea]naphthalen-2-yl}sulfonyl morpholine(10d)was found to be the most potent against A375,HepG2 and Ketr3 with IC50values of 0.65–0.97mol/L,which were 5–20-fold more potent than sorafenib.Compound 10d emerged as a valuable lead for further optimization. 相似文献
64.
Xiang Wang Dr. Qian Xu Dr. Fengtao Fan Dr. Xiuli Wang Dr. Mingrun Li Prof. Zhaochi Feng Prof. Can Li 《化学:亚洲杂志》2013,8(9):2189-2195
By taking advantage of UV‐Raman spectroscopy and high‐resolution TEM (HRTEM), combined with the focused ion beam (FIB) technique, the transformation from GaOOH into α‐Ga2O3 and then into β‐Ga2O3 was followed. We found that the stepwise transformations took place from the surface region before developing into the bulk of single particles without particle agglomeration and growth. During the transformation from GaOOH into α‐Ga2O3, the elimination of water vapor through the dehydroxylation of GaOOH resulted in the formation of micropores in the single particles, whilst maintaining their particle size. For the phase transformation from α‐Ga2O3 into β‐Ga2O3, the nucleation of β‐Ga2O3 was found to occur at the surface defects and this process could be retarded by occupying these defects with a small amount of La2O3. By finely controlling the process of the phase transformation, the β‐Ga2O3 domains gradually developed from the surface into the bulk of the single particles without particle agglomeration. Therefore, the surface structure of the α‐Ga2O3 single particles can be easily tuned and a particle with an α@β core–shell phase structure has been obtained. 相似文献
65.
Dr. Meiling Guo Prof. Dr. Zhaochi Feng Dr. Jan P. Hofmann Prof. Dr. Bert M. Weckhuysen Dr. Fengtao Fan Prof. Dr. Can Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(42):14200-14204
Microporous vanadosilicates with octahedral VO6 and tetrahedral SiO4 units, better known as AM‐6, have been hydrothermally synthesized with different morphologies by controlling the Na/K molar ratio of the initial gel mixtures. The morphology of the AM‐6 materials changed from bulky cube to nanofiber aggregates as the Na/K molar ratio decreased from 1.9 to 0.2. Raman spectroscopy revealed that the VO3? intermediate species plays an important role in the formation of the nanofiber morphology. The orientation of ‐V‐O‐V‐ chains in nanofiber aggregates was examined by confocal polarized micro‐Raman spectroscopy. It was found that these aggregates are assemblies of short ‐V‐O‐V‐ chains perpendicular to the axis of nanofibers. The obtained AM‐6 nanofibers greatly increase the exposed proportion of V? O terminals, and thus improve the catalytic performance. 相似文献
66.
Nazl Turan Yücel Ümmühan Kandemir Ümide Demir
zkay
zgür Devrim Can 《Molecules (Basel, Switzerland)》2021,26(11)
Vortioxetine is a multimodal antidepressant drug that affects several brain neurochemicals and has the potential to induce various pharmacological effects on the central nervous system. Therefore, we investigated the centrally mediated analgesic efficacy of this drug and the mechanisms underlying this effect. Analgesic activity of vortioxetine (5, 10 and 20 mg/kg, p.o.) was examined by tail-clip, tail-immersion and hot-plate tests. Motor performance of animals was evaluated using Rota-rod device. Time course measurements (30–180 min) showed that vortioxetine (10 and 20 mg/kg) administrations significantly increased the response latency, percent maximum possible effect and area under the curve values in all of the nociceptive tests. These data pointed out the analgesic effect of vortioxetine on central pathways carrying acute thermal and mechanical nociceptive stimuli. Vortioxetine did not alter the motor coordination of mice indicating that the analgesic activity of this drug was specific. In mechanistic studies, pre-treatments with p-chlorophenylalanine (serotonin-synthesis inhibitor), NAN-190 (serotonin 5-HT1A receptor antagonist), α-methyl-para-tyrosine (catecholamine-synthesis inhibitor), phentolamine (non-selective α-adrenoceptor blocker), and naloxone (non-selective opioid receptor blocker) antagonised the vortioxetine-induced analgesia. Obtained findings indicated that vortioxetine-induced analgesia is mediated by 5-HT1A serotonergic, α-adrenergic and opioidergic receptors, and contributions of central serotonergic and catecholaminergic neurotransmissions are critical for this effect. 相似文献
67.
Saira Hussain Ata ur Rehman David J. Luckett Syed Muhammad Saqlan Naqvi Christopher L. Blanchard 《Molecules (Basel, Switzerland)》2021,26(7)
Valorization of vegetable oil waste residues is gaining importance due to their high protein and polyphenol contents. Protease inhibitors (PIs), proteins from these abundantly available waste residues, have recently gained importance in treating chronic diseases. This research aimed to use canola meal of genetically diverse Brassica napus genotypes, BLN-3347 and Rivette, to identify PIs with diverse functionalities in therapeutic and pharmacological applications. The canola meal PI purification steps involved: native PAGE and trypsin inhibition activity, followed by ammonium sulfate fractionation, anion exchange, gel filtration, and reverse-phase chromatography. The purified PI preparations were characterized using SDS-PAGE, isoelectric focusing (IEF), and N terminal sequencing. SDS-PAGE analysis of PI preparations under native reducing and nonreducing conditions revealed three polymorphic PIs in each genotype. The corresponding IEF of the genotype BLN-3347, exhibited three acidic isoforms with isoelectric points (pI) of 4.6, 4.0, and 3.9, while Rivette possessed three isoforms, exhibiting two basic forms of pI 8.65 and 9.9, and one acidic of pI 6.55. Purified PI preparations from both the genotypes displayed dipeptidyl peptidase-IV (DPP-IV) and angiotensin-converting enzyme (ACE) inhibition activities; the BLN-3347 PI preparation exhibited a strong inhibitory effect with lower IC50 values (DPP-IV 37.42 µg/mL; ACE 129 µg/mL) than that from Rivette (DPP-IV 67.97 µg/mL; ACE 376.2 µg/mL). In addition to potential human therapy, these highly polymorphic PIs, which can inhibit damaging serine proteases secreted by canola plant pathogens, have the potential to be used by canola plant breeders to seek qualitative trait locus (QTLs) linked to genes conferring resistance to canola diseases. 相似文献
68.
The title compound is a small molecule with many structural variations; it can illustrate a variety of internal hydrogen bonds, among other noncovalent interactions. Here we examine structures displaying hydrogen bonding between carbonyl oxygen and hydroxyl H; between carbonyl oxygen and amino H; hydroxyl H and amino N; hydroxyl O and amino H. We also consider H-bonding in its tautomer 2-oxopropanamide. By extrapolation algorithms applied to Hartree-Fock and correlation energies as estimated in HF, MP2, and CCSD calculations using the cc-pVNZ correlation-consistent basis sets (N = 2, 3, and 4) we obtain reliable relative energies of the isomeric forms. Assuming that such energy differences may be attributed to the presence of the various types of hydrogen bonding, we attempt to infer relative strengths of types of H-bonding. The Atoms in Molecules theory of Bader and the Local Vibrational Modes analysis of Cremer and Kraka are applied to this task. Hydrogen bonds are ranked by relative strength as measured by local stretching force constants, with the stronger =O…HO- > NH…O= > -OH…N well separated from a cluster > NH…O= ≈ >NH…OH ≈ CH…O= of comparable and intermediate strength. Weaker but still significant interactions are of type CH…N which is stronger than CH…OH. 相似文献
69.
Can Ren Shuyu Xiao Junzi Li Prof. Lin Ma Prof. Rui Chen Dr. Chuanxiang Ye Prof. Yang Gao Prof. Chenliang Su Prof. Tingchao He 《化学:亚洲杂志》2021,16(4):309-314
Although the production of near-infrared (NIR)-absorbing organic polymers with an excellent nonlinear optical (NLO) response is vital for various optoelectronic devices and photodynamic therapy, the molecular design and relevant photophysical investigation still remain challenging. In this work, large NLO activity is observed for an NIR-absorbing bithiophene-based polymer with a unique head-to-head linkage in the NIR region. The saturable absorption coefficient and modulation depth of the polymer are determined as ∼−3.5×105 cm GW−1 and ∼32.43%, respectively. Notably, the polymer exhibits an intrinsic nonlinear refraction index up to ∼−9.36 cm2 GW−1, which is six orders of magnitude larger than that of CS2. The maximum molar-mass normalized two-photon absorption cross-section (σ2/M) of this polymer can be up to ∼14 GM at 1200 nm. Femtosecond transient absorption measurements reveal significant spectral overlap between the 2PA and excited state absorption in the 1000–1400 nm wavelength range and an efficient triplet quantum yield of ∼36.7%. The results of this study imply that this NIR-absorbing polymer is promising for relevant applications. 相似文献
70.
为了解决现有镜面偏心测量设备存在的问题,本文研究了一种采用切换镜头和调焦相结合的方法来设计的镜面偏心测量光学系统,使用这个光学系统,既能使被测镜面的曲率半径扩展到-∞~+∞范围,又能保证测量精度。通过Lighttools软件对这个光学系统进行光线追迹,分析其杂光分布,结果表明:准直镜头内部多次反射产生的杂光强度很低,可以忽略。而当被测镜头中存在相邻球心像距的镜面时,产生的杂光强度比较大,在后续的图像处理过程中,必须增强目标图像的对比度。利用研制的镜面偏心测量设备进行测量实验,结果进一步验证了杂光分析的正确性。 相似文献