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At present, the polysaccharide antitumor research is focused on how to further improve the antitumor activity of polysaccharides. The structural modification of polysaccharides can enhance their antitumor activity to a certain ext...
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At present, the polysaccharide antitumor research is focused on how to further improve the antitumor activity of polysaccharides. The structural modification of polysaccharides can enhance their antitumor activity to a certain extent. The antitumor mechanisms of polysaccharide derivatives mainly contain the inducing apoptosis of tumor cells, effecting on the cycle of tumor cells, enhancing the antioxidant activity of organism, activating the body's immune response and inhibiting the tumor angiogenesis. Herein, the common methods of polysaccharide modification, such as sulfation, carboxymethylation, phosphorylation and acetylation, were summarized. At the same time, the effects of chemical modification of polysaccharides on their antitumor mechanisms and activity were analyzed and discussed.
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Artemisinin is one of the most widely prescribed drugs against malaria and has recently received increased attention because of its other potential biological effects. The aim of this review is to summarize recent discoveries of
Artemisinin is one of the most widely prescribed drugs against malaria and has recently received increased attention because of its other potential biological effects. The aim of this review is to summarize recent discoveries of the pharmaceutical effects of artemisinin in basic science along with its mechanistic action, as well as the intriguing results of recent clinical studies, with a focus on its antitumor activity. Scientific evidence indicates that artemisinin exerts its biological activity by generating reactive oxygen species that damage the DNA, mitochondrial depolarization, and cell death. In the present article review, scientific evidence suggests that artemisinin is a potential therapeutic agent for various diseases. Thus, this review is expected to encourage interested scientists to conduct further preclinical and clinical studies to evaluate these biological activities.
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Data on the antitumor activities of ferrocene compounds and the results concerning the mechanisms of their action published between 1995 and 2010 are discussed. The biomedical aspects of the study of ferrocene derivatives are briefly analyzed.
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A short synthesis of 6,6,6-trifluoro-L-acosamine 15 and 6,6,6- trifluoro-L-daunosamine 19 has been accomplished. The pyranose ring system of these carbohydrate analogues was formed by a hetero- Diels - Alder reaction of vinylogous...
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A short synthesis of 6,6,6-trifluoro-L-acosamine 15 and 6,6,6- trifluoro-L-daunosamine 19 has been accomplished. The pyranose ring system of these carbohydrate analogues was formed by a hetero- Diels - Alder reaction of vinylogous imide 11 and ethyl vinyl ether which gave adduct 12a in 40% yield. Hydroboration gave 13 and subsequent hydrogenolytic removal of the ( R)- 2-phenylethyl chiral auxiliary gave ethyl 6,6,6- trifluoro-L-acosaminide 14. Acid hydrolysis furnished target 15. Glycoside 13 was N-trifluoroacetylated to give 16, the structure was confirmed by single crystal X-ray diffraction. The C-4 stereochemistry of 16 was inverted by Swern oxidation of the 4-OH group, and subsequent borohydride reduction to give 17. Hydrogenolytic removal of the auxiliary gave ethyl-6,6,6-trifluoro-L-daunosaminide 18. Acid hydrolysis provided 19.
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Certain 17 beta-aminoderivatives of 5 alpha-steroids based on tigogenin were synthesized and their antitumor activity was studied. The structures of the synthesized compounds were confirmed by NMR and IR spectroscopy and mass spectrometry.
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Tricrozarin B (1) was isolated from bulbs of Tritonia crocosmaeflora Lemoine (Iridaceae) [1]. It, lomazarin (2) [2, 3], and tricrozarin A [4] are rare examples of polymethoxynaphthazarins isolated from higher plants. Tricrozarin B...
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Tricrozarin B (1) was isolated from bulbs of Tritonia crocosmaeflora Lemoine (Iridaceae) [1]. It, lomazarin (2) [2, 3], and tricrozarin A [4] are rare examples of polymethoxynaphthazarins isolated from higher plants. Tricrozarin B exhibited cytotoxic activity in vitro against Hela-S_3 cells and antitumor activity in vivo against murine sarcoma S-180 [1] and melanoma B-16 [5].
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Perifosine, a.k.a. KRX-0401 [octadecyl-(1,1-dimethylpiperidinio- 4-yl)-phoshate] is a synthetic novel alkylphospholipid, member of a new class of antitumor agents which target cell membranes, inhibit Akt activation and induce apop...
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Perifosine, a.k.a. KRX-0401 [octadecyl-(1,1-dimethylpiperidinio- 4-yl)-phoshate] is a synthetic novel alkylphospholipid, member of a new class of antitumor agents which target cell membranes, inhibit Akt activation and induce apoptosis. Perifosine inhibits Akt activation regardless of the interaction ligand/receptor tyrosine kinase because it is able to exert its effects directly on the activated form of Akt; furthermore, Perifosine does not directly affect activity of PI3-K or phosphoinositide-dependent kinase 1 (PDK1) and induces p21cip1 expression leading to G2/M phase cell accumulation. p21cip1 induction is due to activation of Erk signalling pathway by Perifosine, since Erk activation promotes the phosphorylation of Sp1 in known Erk threonine residues (Thr 453/739), thereby leading to increased Sp1 binding and enhanced p21cip1 transcription.
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Biological effects of different anthraquinones and particularlyanthracenetetraone are related to various substitutions and compounds with lower anti-proliferative activity tended to show higher anti-tumor activity [1,2]. So confor...
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Biological effects of different anthraquinones and particularlyanthracenetetraone are related to various substitutions and compounds with lower anti-proliferative activity tended to show higher anti-tumor activity [1,2]. So conformational uniqueness of each derivative may provoke or diminish biological activity of the molecule. In the present study, relative energies, dipole moments, HOMO–LUMO energies, kmax values, and charge densities of anthracentetraone and its eight structural isomers were calculated by the ab initio molecular orbital calculations using the GAUSSIAN 98 program [3]. Initial geometry optimizations and density functional theory were carried out at the B3LYP/6- 31G* and B3LYP/6-311+G** levels, and zero-point energies, obtained at these levels, were scaled by a factor of 0.9135. HOMO–LUMO energies are obtained for fully optimized geometries, therefore, kmax values are obtained by the following equation
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Oleanolic acid has previously been shown to possess PI3K inhibitory activity, thus, the purpose of this work was to generate a series of derivatives that improve the potency. Twenty rationally designed oleanolic acid derivatives w...
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Oleanolic acid has previously been shown to possess PI3K inhibitory activity, thus, the purpose of this work was to generate a series of derivatives that improve the potency. Twenty rationally designed oleanolic acid derivatives were synthesized and tested the cytotoxicity and PI3K inhibitory activity. The results suggested that attachment of additional structural elements such as association of thiazole group to A ring and insertion of phenylurea group was important for increasing activities. The most active derivative was compound II2, which exhibited PI3K inhibitory activity (IC50 = 58.42 nmol/l) and improved interaction with activity site of PI3K according with docking studies.
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Six organotin(IV) carboxylates of the type R_2SnL_2 [R = CH_3 (1), n-C_4H_9 (2), n-C_8H_(17) (3)] and R_3SnL [R = CH_3 (4), n-C_4H_9 (5), C_6H_5 (6), where L = 2-(4-ethoxybenzylidene) butanoic acid, have been synthesized and chara...
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Six organotin(IV) carboxylates of the type R_2SnL_2 [R = CH_3 (1), n-C_4H_9 (2), n-C_8H_(17) (3)] and R_3SnL [R = CH_3 (4), n-C_4H_9 (5), C_6H_5 (6), where L = 2-(4-ethoxybenzylidene) butanoic acid, have been synthesized and characterized by elemental analysis, FT-IR and NMR (~1H, ~(13)C). The complex (1) was also analyzed by single crystal X-ray analysis. The complexes were screened for antimicrobial, cytotoxic and anti-tumor activities. The results showed significant activity in each area of the activity with few exceptions. DNA interactions studies of ligand HL and representative complex 2 were investigated by UV-Visible absorption spectroscopy and viscosity measurements. The results showed that both ligand HL and complex 2 interact with SS-DNA via intercalation as well as minor groove binding.
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