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排序方式: 共有264条查询结果,搜索用时 34 毫秒
1.
Oxana Kazakova Irina Smirnova Elena Tretyakova Ren Csuk Sophie Hoenke Lucie Fischer 《International journal of molecular sciences》2021,22(4)
Semi-synthetic triterpenoids, holding an amino substituted seven-membered A-ring (azepano-ring), which could be synthesized from triterpenic oximes through a Beckmann type rearrangement followed by a reduction of lactame fragment, are considered to be novel promising agents exhibiting anti-microbial, alpha-glucosidase, and butyrylcholinesterase inhibitory activities. In this study, in an attempt to develop new antitumor candidates, a series of A-ring azepano- and 3-amino-3,4-seco-derivatives of betulin, oleanolic, ursolic, and glycyrrhetinic acids were evaluated for their cytotoxic activity against five human cancer cell lines and non-malignant mouse fibroblasts by means of a colorimetric sulforhodamine assay. Azepanoallobetulinic acid amide derivative 11 was the most cytotoxic compound of this series but showed little selectivity between the different human tumor cell lines. Flow cytometry experiments showed compound 11 to act mainly by apoptosis (44.3%) and late apoptosis (21.4%). The compounds were further screened at the National Cancer Institute towards a panel of 60 cancer cell lines. It was found that compounds 3, 4, 7, 8, 9, 11, 15, 16, 19, and 20 showed growth inhibitory (GI50) against the most sensitive cell lines at submicromolar concentrations (0.20–0.94 μM), and their cytotoxic activity (LC50) was also high (1–6 μM). Derivatives 3, 8, 11, 15, and 16 demonstrated a certain selectivity profile at GI50 level from 5.16 to 9.56 towards K-562, CCRF-CEM, HL-60(TB), and RPMI-8226 (Leukemia), HT29 (Colon cancer), and OVCAR-4 (Ovarian cancer) cell lines. Selectivity indexes of azepanoerythrodiol 3 at TGI level ranged from 5.93 (CNS cancer cell lines SF-539, SNB-19 and SNB-75) to 14.89 for HCT-116 (colon cancer) with SI 9.56 at GI50 level for the leukemia cell line K-562. The present study highlighted the importance of A-azepano-ring in the triterpenic core for the development of novel antitumor agents, and a future aim to increase the selectivity profile will thus lie in the area of modifications of azepano-triterpenic acids at their carboxyl group. 相似文献
2.
Gavrina P. S. Soboleva O. S. Podoskin A. A. Kazakova A. E. Kapitonov V. A. Slipchenko S. O. Pikhtin N. A. 《Semiconductors》2020,54(8):882-889
Semiconductors - The spatial and temporal dynamics of the optical loss and carrier density in the heterostructure of a semiconductor laser with a segmented contact are studied using an optical... 相似文献
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Butkalyuk P. S. Butkalyuk I. L. Agapov A. A. Kupriyanov A. S. Kazakova E. V. 《Radiochemistry》2021,63(1):21-27
Radiochemistry - The solubility of radium fluoride in water was determined. Radium was purified by the chromatographic method with a BioRad AG-50×8 (NH4+) sorbent (200–400 mesh). The... 相似文献
7.
Kholdeeva Oxana A. Ivanchikova Irina D. Maksimchuk Nataliya V. Melgunov Maxim S. Chang Jong-San Guidotti Matteo Shutilov Alexei A. Zaikovskii Vladimir I. 《Topics in Catalysis》2014,57(17):1377-1384
Catalytic properties of Ti-containing porous solids were compared in the oxidation of 2,3,6-trimethylphenol (TMP) with H2O2 to produce 2,3,5-trimethyl-1,4-benzoquinone (TMBQ, vitamin E key intermediate). Mesoporous titanium–silicates with di(oligo)nuclear Ti centers, metal–organic framework MIL-125 and amorphous TiO2 demonstrated 100 % selectivity toward TMBQ. Titanium–silicates prepared by evaporation-induced self-assembly revealed superior performance in terms of product yield and catalyst reusability.
相似文献8.
High Temperature - The development of the initial stage of instability of a contact boundary of colliding metal plates has been numerically simulated. The mathematical model is based on the Euler... 相似文献
9.
Taran Oxana P. Yashnik Svetlana A. Boltenkov Vadim V. Parkhomchuk Ekaterina V. Sashkina Kseniya A. Ayusheev Artemiy B. Babushkin Dmitrii E. Parmon Valentin N. 《Topics in Catalysis》2019,62(5-6):491-507
Topics in Catalysis - The process of synthesis of formic acid via partial peroxide oxidation of methane over Fe-MFI zeolites, as well as the influence of the catalyst activation by oxalic acid on... 相似文献
10.
Stanislav R. Kurpe Sergei Yu. Grishin Alexey K. Surin Alexander V. Panfilov Mikhail V. Slizen Saikat D. Chowdhury Oxana V. Galzitskaya 《International journal of molecular sciences》2020,21(24)
At present, much attention is paid to the use of antimicrobial peptides (AMPs) of natural and artificial origin to combat pathogens. AMPs have several points that determine their biological activity. We analyzed the structural properties of AMPs, as well as described their mechanism of action and impact on pathogenic bacteria and viruses. Recently published data on the development of new AMP drugs based on a combination of molecular design and genetic engineering approaches are presented. In this article, we have focused on information on the amyloidogenic properties of AMP. This review examines AMP development strategies from the perspective of the current high prevalence of antibiotic-resistant bacteria, and the potential prospects and challenges of using AMPs against infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). 相似文献