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431.
Natalie J. Waleska Dr. Fabian Düll Dr. Philipp Bachmann Felix Hemauer Johann Steinhauer Dr. Christian Papp 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(68):17087-17093
The reactivity of iron nanocluster arrays on h-BN/Rh(111) was studied using in situ high-resolution X-ray photoelectron spectroscopy. The morphology and reactivity of the iron nanoclusters (Fe-NCs) were investigated by CO adsorption. On-top and hollow/edge sites were determined to be the available adsorption sites on the as-prepared Fe-NCs and CO dissociation was observed at 300 K. C- and O-precovered Fe-NCs showed no catalytic activity towards CO dissociation because the hollow/edge sites were blocked by the C and O atoms. Therefore, these adsorption sites were identified to be the most active sites of the Fe-NCs. 相似文献
432.
Natalie Schäfer Michael Bühler Lisa Heyer Dr. Merle I. S. Röhr Priv.-Doz. Dr. Florian Beuerle 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(19):6077-6085
A highly strained covalent organic cage compound was synthesized from hexahydroxy tribenzotriquinacene (TBTQ) and a meta-terphenyl-based diboronic acid with an additional benzoic acid substituent in 2’-position. Usually, a 120° bite angle in the unsubstituted ditopic linker favors the formation of a [4+6] cage assembly. Here, the introduction of the benzoic acid group is shown to lead to a perfectly preorganized circular hydrogen-bonding array in the cavity of a trigonal-bipyramidal [2+3] cage, which energetically overcompensates the additional strain energy caused by the larger mismatch in bite angles for the smaller assembly. The strained cage compound was analyzed by mass spectrometry and 1H, 13C and DOSY NMR spectroscopy. DFT calculations revealed the energetic contribution of the hydrogen-bonding template to the cage stability. Furthermore, molecular dynamics simulations on early intermediates indicate an additional kinetic effect, as hydrogen bonding also preorganizes and rigidifies small oligomers to facilitate the exclusive formation of smaller and more strained macrocycles and cages. 相似文献
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435.
Natalie A. Haverkate Euphemia Leung Lisa I. Pilkington David Barker 《Molecules (Basel, Switzerland)》2022,27(3)
3-Amino-2-arylcarboxamido-thieno[2,3-b]pyridines have been shown to have anti-proliferative activity, but are also known to have poor solubility. This has been previously proposed to be due to their extensive planarity, which allows for intermolecular stacking and crystal packing. We herein report the synthesis of fifteen novel thieno[2,3-b]pyridines that have incorporated bulky, but easily cleavable, ester and carbonate functional groups in an effort to decrease crystal packing. The addition of these ‘prodrug-like’ moieties into the thieno[2,3-b]pyridine resulted in compounds with increased activity against HCT-116 colon cancer cells and the triple-negative breast cancer cell line MDA-MB-231. 相似文献
436.
Tyler C. Beck Kendra Springs Jordan E. Morningstar Catherine Mills Andrew Stoddard Lilong Guo Kelsey Moore Cortney Gensemer Rachel Biggs Taylor Petrucci Jennie Kwon Kristina Stayer Natalie Koren Jaclyn Dunne Diana Fulmer Ayesha Vohra Le Mai Sarah Dooley Julianna Weninger Yuri Peterson Patrick Woster Thomas A. Dix Russell A. Norris 《Molecules (Basel, Switzerland)》2022,27(12)
Cancer is the second most common cause of death in the United States, accounting for 602,350 deaths in 2020. Cancer-related death rates have declined by 27% over the past two decades, partially due to the identification of novel anti-cancer drugs. Despite improvements in cancer treatment, newly approved oncology drugs are associated with increased toxicity risk. These toxicities may be mitigated by pharmacokinetic optimization and reductions in off-target interactions. As such, there is a need for early-stage implementation of pharmacokinetic (PK) prediction tools. Several PK prediction platforms exist, including pkCSM, SuperCypsPred, Pred-hERG, Similarity Ensemble Approach (SEA), and SwissADME. These tools can be used in screening hits, allowing for the selection of compounds were reduced toxicity and/or risk of attrition. In this short commentary, we used PK prediction tools in the optimization of mitogen activated extracellular signal-related kinase kinase 1 (MEK1) inhibitors. In doing so, we identified MEK1 inhibitors with retained activity and optimized predictive PK properties, devoid of hERG inhibition. These data support the use of publicly available PK prediction platforms in early-stage drug discovery to design safer drugs. 相似文献
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438.
Dr. Susan D. Wiedner Lindsey N. Anderson Natalie C. Sadler William B. Chrisler Vamsi K. Kodali Dr. Richard D. Smith Dr. Aaron T. Wright 《Angewandte Chemie (International ed. in English)》2014,53(11):2919-2922
A multimodal activity‐based probe for targeting acidic organelles was developed to measure subcellular native enzymatic activity in cells by fluorescence microscopy and mass spectrometry. A cathepsin‐reactive warhead conjugated to a weakly basic amine and a clickable alkyne, for subsequent appendage of a fluorophore or biotin reporter tag, accumulated in lysosomes as observed by structured illumination microscopy (SIM) in J774 mouse macrophage cells. Analysis of in vivo labeled J774 cells by mass spectrometry showed that the probe was very selective for cathepsins B and Z, two lysosomal cysteine proteases. Analysis of starvation‐induced autophagy, a catabolic pathway involving lysosomes, showed a large increase in the number of tagged proteins and an increase in cathepsin activity. The organelle‐targeting of activity‐based probes holds great promise for the characterization of enzyme activities in the myriad diseases linked to specific subcellular locations, particularly the lysosome. 相似文献
439.
Natalie Smirnova Anna Eremenko Olga Rusina Werner Hopp Lubomir Spanhel 《Journal of Sol-Gel Science and Technology》2001,22(1-2):109-113
Wet chemical synthesis and preliminary photocatalytical characteristics of titania and Fe(III)-containing TiO2 layers are presented. A highly stable coating colloids could be prepared under base- as well as acid-catalyzed condensation conditions. Structural properties of the as-prepared wet gels and sintered films were investigated using SEM, TEM, XRD as well as optical absorption spectroscopy, DTA-TG analysis and photomineralisation studies. X-ray amorphous wet titania gel layers start to crystallize at 500°C forming the characteristic anatase phase. In the presence of iron ions (Fe/Ti = 1), nanocrystalline FeTiO3 ilmenite phase forms. Both TiO2 and Fe-containing TiO2 films demonstrate a photocatalytic activity in the process of the photomineralization of dichloroacetic acid. 相似文献
440.
The synthesis and characterization of a seriesof 4 ‐ (4′‐ n ‐alkoxybenzylideneimino)phenyl‐mercury<?tw=97.2%>(II) dithizonates, [CnH2n+1OC6H4CHNC6H4Hg<?tw>(Hdptc)] (H2dptc = 1,5‐diphenylthiocarbazone = dithizone; n = 1, 4, 12, 14 or 18), is described. The intermediate long‐chain organomercury(II) acetates were obtained by condensation of 4‐aminophenylmercury(II) acetate with the appropriate 4‐n‐alkoxybenzaldehydes. The thermal behaviour of the complexes was studied by polarized optical microscopy and differential scanning calorimetry but revealed no mesophases. All of the complexes, however, were reversibly photochromic (yellow ⇌ blue) upon irradiation of chloroform solutions with visible light, and the half‐lives of the metastable blue forms were substantially increased relative to that of the parent mercury(II) bis(dithizonate). The compounds were not photochromic in the solid state. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献