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Dr. Ivan A. Yaremenko Dr. Paolo Coghi Parichat Prommana Congling Qiu Peter S. Radulov Yuanqing Qu Yulia Yu. Belyakova Dr. Enrico Zanforlin Dr. Vladimir A. Kokorekin Yuki Yu Jun Wu Prof. Fabrice Fleury Dr. Chairat Uthaipibull Dr. Vincent Kam Wai Wong Prof. Alexander O. Terent'ev 《ChemMedChem》2020,15(13):1118-1127
This article discloses a new horizon for the application of peroxides in medical chemistry. Stable cyclic peroxides are demonstrated to have cytotoxic activity against cancer cells; in addition a mechanism of cytotoxic action is proposed. Synthetic bridged 1,2,4,5-tetraoxanes and ozonides were effective against HepG2 cancer cells and some ozonides selectively targeted liver cancer cells (the selectivity indexes for compounds 11 b and 12 a are 8 and 5, respectively). In some cases, tetraoxanes and ozonides were more selective than paclitaxel, artemisinin, and artesunic acid. Annexin V flow-cytometry analysis revealed that the active ozonides 22 a and 23 a induced cell death of HepG2 by apoptosis. Further study showed that compounds 22 a and 23 a exhibited a strong inhibitory effect on P-glycoprotein (P-gp/ABCB5)-overexpressing HepG2 cancer cells. ABCB5 is a key player in the multidrug-resistant phenotype of liver cancer. Peroxides failed to demonstrate a direct correlation between oxidative potential and their biological activity. To our knowledge this is the first time that peroxide diastereoisomers have been found to show stereospecific antimalarial action against the chloroquine-sensitive 3D7 strain of Plasmodium falciparum. Stereoisomeric ozonide 12 b is 11 times more active than stereoisomeric ozonide 12 a (IC50=5.81 vs 65.18 μm ). Current findings mean that ozonides merit further investigation as potential therapeutic agents for drug-resistant hepatocellular carcinoma. 相似文献
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Intensified and safe ozonolysis of fatty acid methyl esters in liquid CO2 in a continuous reactor 下载免费PDF全文
Michael D. Lundin Andrew M. Danby Geoffrey R. Akien Padmesh Venkitasubramanian Kevin J. Martin Daryle H. Busch Bala Subramaniam 《American Institute of Chemical Engineers》2017,63(7):2819-2826
We demonstrate a continuous reactor for performing the ozonolysis of fatty acid methyl esters (FAMEs) using liquid CO2 as solvent. The fast reaction kinetics allows the use of small‐volume reactors to completely convert the FAMEs, forming secondary ozonides as the primary products. The short residence times also help maximize the yields of the secondary ozonides by minimizing over‐oxidation and the formation of oligomeric products. The liquid CO2 medium promotes safe reactor operation by providing an essential fraction of overall reactor cooling and by diluting the vapor phase organics. We also demonstrate a continuous stirred reactor for the safe thermal decomposition of the secondary ozonides to their corresponding acids and aldehydes. Using a lumped kinetic model for the thermal decomposition of the ozonolysis products, we estimate activation energy values of 108.6 ± 0.6 kJ mol?1 for the decomposition of secondary ozonides and 122 ± 3 kJ mol?1 for the decomposition of the undesired oligomeric species. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2819–2826, 2017 相似文献
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Martin Sterrer Thomas Berger O. Diwald Erich Knözinger Alain Allouche 《Topics in Catalysis》2007,46(1-2):111-119
The adsorption properties of oxygen radicals on the surface of polycrystalline oxides can provide relevant information about
the functionality of specific surface sites in oxidation catalysis. Using electron paramagnetic resonance spectroscopy, we
investigated O2 adsorption at MgO nanocrystal surfaces which were previously enriched with O− radicals i.e. trapped hole centers. On dehydroxylated particle surfaces, two ozonide radical types O
3
−
were isolated as adsorbates and the related energies for O2 adsorption were found to be 55 ± 5 kJ mol−1 and 100 ± 5 kJ mol−1. The respective adsorption sites are assigned to hole centers trapped on oxygen terminated corners and cation vancancies,
respectively.
In addition, O
3
−
ions were also employed as probes for electron trapping sites on partially hydroxylated sample surfaces. Five types of O− radicals emerge from surface colour centre bleaching with N2O, but only two of them adsorb O2 at room temperature. A connection between the well-characterized (H+)(e-) defect – an electron trapped in close vicinity of a nearby proton [Chiesa et al. J. Phys. Chem. B 109 (2005) 7314] – and
one ozonide type which exhibits significant magnetic coupling with an adjacent proton, was established on the basis of their
production parameter dependence. Although the g tensor of an O3
− species reflects the properties of the radical itself rather than the structure of the adsorption site, the related signatures
are proposed to serve also as spectroscopic fingerprints for catalytically relevant surface anion environments. 相似文献
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以天然产物松节油的主要成分α-蒎烯和醇为原料,二氯甲烷为溶剂,经臭氧氧化制得α-蒎烯臭氧化物,臭氧化物不加分离直接在三乙胺(TEA)催化下经乙酸酐重排(AA)裂解,一锅法合成了6种蒎酮酸酯类化合物。考察了乙酸酐用量、三乙胺用量、反应时间和反应温度等条件对蒎酮酸酯收率的影响,并通过正交试验对合成条件进行了优化。优化的实验条件为:nAA/nα-蒎烯 = 3.0∶1,nTEA/nα-蒎烯 = 0.75∶1,反应时间为60 min,反应温度为30 ℃,在该条件下合成的6种蒎酮酸酯收率均在60%以上,并采用1H NMR、13C NMR、IR、MS对6种化合物的结构进行了表征。该方法操作简便,条件温和,且收率高,是合成蒎酮酸酯类化合物的一种简易可行的方法。 相似文献
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以天然产物松节油的主要成分α-蒎烯和醇为原料,二氯甲烷为溶剂,经臭氧氧化制得α-蒎烯臭氧化物,臭氧化物不加分离直接在三乙胺(TEA)催化下经乙酸酐重排(AA)裂解,一锅法合成了6种蒎酮酸酯类化合物。考察了乙酸酐用量、三乙胺用量、反应时间和反应温度等条件对蒎酮酸酯收率的影响,并通过正交试验对合成条件进行了优化。优化的实验条件为:nAA/nα-蒎烯=3.0∶1,nTEA/nα-蒎烯=0.75∶1,反应时间为60 min,反应温度为30℃,在该条件下合成的6种蒎酮酸酯收率均在60%以上,并采用1H NMR、13C NMR、IR、MS对6种化合物的结构进行了表征。该方法操作简便,条件温和,且收率高,是合成蒎酮酸酯类化合物的一种简易可行的方法。 相似文献
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