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641.
Leili Jalili‐Baleh Narges Mohammadi Mehdi Khoobi Leila Ma'mani Alireza Foroumadi Abbas Shafiee 《Helvetica chimica acta》2013,96(8):1601-1609
Various monospiro‐2‐amino‐4H‐pyran derivatives have been synthesized in high yields (via three‐component coupling of ninhydrin or different isatins with malononitrile and 1,3‐dicarbonyl compounds) in the presence of catalytic amount of propane‐1‐sulfonic acid‐modified magnetic hydroxyapatite nanoparticles in H2O. Due to easy magnetic removal of nanocatalyst and applying of H2O as solvent, this protocol enhanced product purity, and promised economic as well as environmental benefits, exemplifying a waste‐free chemistry. More importantly, the catalyst could be easily recycled for more than five times without loss of activity. 相似文献
642.
Three-component, one-pot synthesis of 4,6-diarylpyrimidin-2(1H)-ones and 9-phenyl-8-oxa-10,12-diaza-tricyclo[7.3.1.02,7]trideca-2(7),3,5-trien-11-one by condensing acetophenone derivatives, aldehydes, and urea in the presence of trimethylsilyl chloride using a catalytic amount of H6P2W18O62-18H2O under solvent-free conditions is reported. 相似文献
643.
Leonetti Paolo Miller Harry I. Wieren Leila Miller-Van 《Periodica Mathematica Hungarica》2019,78(2):152-156
Periodica Mathematica Hungarica - Let S be the set of subsequences $$(x_{n_k})$$ of a given real sequence $$(x_n)$$ which preserve the set of statistical cluster points. It has been recently shown... 相似文献
644.
A simple synthesis of 1,2,3,5-tetrasubstituted pyrrole derivatives from the reaction of enaminone withα-haloketones,under solvent-free conditions,is described. 相似文献
645.
Chia-Yen Wu Dosh Whye Lisa Glazewski Leila Choe Douglas Kerr Kelvin H Lee Robert W Mason Wenlan Wang 《BMC neuroscience》2011,12(1):25
Background
Deletion or mutation(s) of the survival motor neuron 1 (SMN1) gene causes spinal muscular atrophy (SMA), a neuromuscular disease characterized by spinal motor neuron death and muscle paralysis. Complete loss of the SMN protein is embryonically lethal, yet reduced levels of this protein result in selective death of motor neurons. Why motor neurons are specifically targeted by SMN deficiency remains to be determined. In this study, embryonic stem (ES) cells derived from a severe SMA mouse model were differentiated into motor neurons in vitro by addition of retinoic acid and sonic hedgehog agonist. Proteomic and western blot analyses were used to probe protein expression alterations in this cell-culture model of SMA that could be relevant to the disease. 相似文献646.
A rapid and efficient one-pot method for the synthesis of 4,6-diarylpyrimidin-2(1H)-ones and related heterocycles is described. The condensation of acetophenone derivatives, aldehydes and urea in the presence of sulfamic acid was employed to synthesize a variety of pyrimidinones in moderate to excellent yields. The scope and limitations of this method are described. 相似文献
647.
Leila Takahashi-Ruiz Joseph D. Morris Phillip Crews Tyler A. Johnson April L. Risinger 《Molecules (Basel, Switzerland)》2022,27(13)
Microtubule-stabilizing agents (MSAs) are a class of compounds used in the treatment of triple-negative breast cancer (TNBC), a subtype of breast cancer where chemotherapy remains the standard-of-care for patients. Taxanes like paclitaxel and docetaxel have demonstrated efficacy against TNBC in the clinic, however new classes of MSAs need to be identified due to the rise of taxane resistance in patients. (−)-Zampanolide is a covalent microtubule stabilizer that can circumvent taxane resistance in vitro but has not been evaluated for in vivo antitumor efficacy. Here, we determine that (−)-zampanolide has similar potency and efficacy to paclitaxel in TNBC cell lines, but is significantly more persistent due to its covalent binding. We also provide the first reported in vivo antitumor evaluation of (−)-zampanolide where we determine that it has potent and persistent antitumor efficacy when delivered intratumorally. Future work on zampanolide to further evaluate its pharmacophore and determine ways to improve its systemic therapeutic window would make this compound a potential candidate for clinical development through its ability to circumvent taxane-resistance mechanisms. 相似文献
648.
649.
Aiza Azam Gulzar Muhammad Muhammad Shahbaz Aslam Muhammad Mudassir Iqbal Muhammad Arshad Raza Naeem Akhtar Muhammad Ajaz Hussain Noreen Sajjad Asad Syed Ali H. Bahkali Zahid Shafiq 《应用有机金属化学》2023,37(1):e6923
The multifunctional zinc oxide nanoparticles are synthesized using a cost-effective, efficient, eco-friendly, simple, and clean synthesis approach. Herein, we reported the antibacterial and wound healing potential of zinc oxide nanoparticles (ZnO-NPs) prepared using psyllium gel (PG) as the reducing and stabilizing agent. The PG-mediated zinc oxide nanoparticles (PG-ZnO-NPs) were characterized using UV–Vis, photoluminescence (PL), FTIR, XRD, Raman, and SEM. UV–Vis spectral studies confirmed the surface plasmonic resonance (SPR) band at 364 nm. PL results demonstrated the fluorescent or emission nature of PG-ZnO-NPs. FTIR analysis confirmed characteristic peaks at 873.82 and 619.88 cm−1 due to the tetrahedral coordination of zinc and the formation of the Zn-O bond. XRD and Raman confirm the formation of PG-ZnO-NPs, whereas SEM analysis revealed PG-ZnO-NPs are rod-shaped, having hexagonal prism-like bases, and EDX exhibited the elemental composition of PG-ZnO-NPs. The as-synthesized PG-ZnO-NPs possessed prominent microbicidal potential against gram-positive (Bacillus subtilis and Bacillus licheniformis) and gram-negative (Escherichia coli and Salmonella shigella) bacterial strains in terms of zone of inhibition (ZOI), minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). In vivo biological investigations with mice show that the synthesized PG-ZnO-NPs possess outstanding biocompatibility and wound healing potential. PG-ZnO-NPs dressing significantly speeds up full-thickness wound repair by triggering a decrease in MMP-1 and MMP-2 and escalating the mRNA levels of collagen types (I & III) and fibronectin. Thus, our work validates that the inclusion of PG-ZnO-NPs in dressing shows excellent potential for acute wound management. 相似文献
650.
The reaction of 2‐thioxo‐4‐thiazolidinone ( 1a ) with phosphorus ylides 2a and 2b afforded compounds 5 and 6. On the other hand, formylmethylenetriphenylphosphorane (2c) reacts with 1a and its N‐methyl derivative 1b to give the new complicated phosphonium ylides 7a,b, respectively. Reactions of 1b with ylides 2a and 2d gave rise to the olefinic compound 8 and the new phosphorane product 9. Moreover, dialkyl phosphites 3a,b and trialkyl phosphites 4a–c react with 1a to give both the alkylated products 10a–c and the dimeric compounds 11,12. A mechanism is proposed to explain the formation of the new products.© 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 337–341, 1999 相似文献