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Zi Jie Lin Jared Bies Shanina S. Johnson John D. Gorden Jacqueline F. Strickland Monica Frazier Jonathan M. Meyers Kerri L. Shelton 《Journal of heterocyclic chemistry》2019,56(2):533-538
A series of 1,4‐N,N′‐bis‐substituted 1,2,4‐triazolium bromide salts were synthesized and tested for anti‐proliferative activity. 1,4‐Bis(naphthalen‐2‐ylmethyl)‐1,2,4‐triazolium bromide ( 2 ) showed activity against MDA‐MB‐468 breast cancer and PC‐3 prostate cancer cell lines. 相似文献
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Significant Enhancement in the Efficiency and Selectivity of Iron‐Catalyzed Oxidative Cross‐Coupling of Phenols by Fluoroalcohols 下载免费PDF全文
Eden Gaster Yulia Vainer Almog Regev Dr. Sachin Narute Dr. Kavitha Sudheendran Aviya Werbeloff Hadas Shalit Dr. Doron Pappo 《Angewandte Chemie (International ed. in English)》2015,54(14):4198-4202
Significant enhancement of both the rate and the chemoselectivity of iron‐catalyzed oxidative coupling of phenols can be achieved in fluorinated solvents, such as 1,1,1,3,3,3‐hexafluoropropan‐2‐ol (HFIP), 2,2,2‐trifluoroethanol (TFE), and 1‐phenyl‐2,2,2‐trifluoroethanol. The generality of this effect was examined for the cross‐coupling of phenols with arenes and polycyclic aromatic hydrocarbons (PAHs) and of phenol with β‐dicarbonyl compounds. The new conditions were utilized in the synthesis of 2′′′‐dehydroxycalodenin B in only four synthetic steps. 相似文献
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Immo Weber Frank W. Heinemann Panagiotis Bakatselos Ulrich Zenneck 《Helvetica chimica acta》2007,90(4):834-845
A pressure‐controlled procedure for the SN1 reaction of rac‐1‐[(dimethylamino)methyl]‐2‐(tributylstannyl)ferrocene ( 1 ) to rac‐1‐(phthalimidomethyl)‐2‐(tributylstannyl)ferrocene ( 2 ) was developed. Pd0‐Catalyzed Stille coupling of 2 with iodobenzene afforded rac‐1‐phenyl‐2‐(N‐phthalimidomethyl)ferrocene ( 5 ) in 74% yield; after trace enrichment by crystallization of the combined mother liquors, one single crystal of each, 5 , catalysis intermediate trans‐iodo(σ‐phenyl)bis(triphenylarsino)palladium(II) ( 7 ), trans‐diiodobis(triphenylarsino)palladium(II) ( 8 ), and rac‐2,2′‐bis(phthalimidomethyl)‐1,1′‐biferrocene ( 9 ) could be isolated by crystal sorting under a microscope and characterized by X‐ray crystal structure analysis. Furthermore, 5 was deprotected to amine ( 11 ), which does even survive the Birch reduction to rac‐1‐(aminomethyl)‐2‐(cyclohexa‐2,5‐dienyl)ferrocene ( 12 ). 相似文献
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Mahlako Malesele Nkogatse Motsehoa Cynthia Ramotsehoa Frederick Christofel Eloff Caradee Yael Wright 《Photochemistry and photobiology》2019,95(1):439-445
The exposure of outdoor car guards to solar ultraviolet radiation (UVR), the majority with deeply pigmented skin, to solar UVR was measured for five consecutive days during early spring (September 2017) in South Africa using electronic UVR dosimeters attached to the upper arm of each participant. The exposure of the nape of the neck, forehead, nose, cheek and hand was extrapolated from the measurements. The onsite ambient solar UVR on a flat, horizontal, unshaded surface was measured concurrently. The sun‐related knowledge, behavior and attitudes of the car guards were evaluated using questionnaires. Total personal daily solar UVR exposure as a percentage of the ambient solar UVR exposure was 24%. The exposure of car guards on several body sites was in excess of the occupational threshold limit value. Sleeved shirts and hats were the most commonly used sun protection measures (worn by 70% and 80%, respectively). Considering the high levels of solar UVR reported on most days throughout the year in South Africa, more studies quantifying the personal exposure of outdoor workers in both the informal and formal sectors are necessary. 相似文献
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Gantumur Battogtokh Oyuntuya Gotov Nithya Subrahmanyam Young Tag Ko Hamidreza Ghandehari 《Macromolecular bioscience》2019,19(7)
Photodynamic therapy (PDT) is a promising cancer treatment approach. However, the photosensitizers (PS) used for PDT are often limited by their poor solubility and selectivity for tumors. The goal of this study is to improve water solubility and delivery of the photosensitizer 2‐[1‐hexyloxyethyl]‐2‐divinyl pyropheophorbide‐a (HPPH) to breast cancer cells. An N‐(2‐hydroxypropyl)methacrylamide (HPMA) copolymer–HPPH photosensitizer conjugate is synthesized with heat shock receptor glucose‐regulated protein 78 (GRP78), targeting to GRP78 receptors of MCF‐7 cells, which are upregulated under mild hyperthermia. It is found that the uptake of the GRP78 targeted pep‐HPMA‐HPPH copolymer conjugate in MCF‐7 cells is improved through heat induction. Under mild hyperthermia the targeted copolymers are more effective compared to free HPPH. These results show potential for the utility of mild hyperthermia and copolymer delivery vehicles to enhance the efficacy of photodynamic therapy. 相似文献
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林长裕 《广东微量元素科学》2017,24(5)
目的探讨乳腺癌患者化疗效果对血清中钙(Ca)、磷(P)、镁(Mg)以及锌(Zn)含量的影响。方法选取普宁市人民医院进行化疗的乳腺癌患者80例作为化疗组,观察患者化疗前后血清中Ca、P、Mg以及Zn的水平变化,另选80例健康女性作为健康人组,检测其血清Ca、P、Mg、Zn水平,并进行对比分析。结果化疗组Ca、Mg含量明显低于健康人组(P0.05),Zn含量明显高于健康人组(P0.05),P含量与健康人组相比无统计学意义(P0.05);化疗后Ca、Mg含量显著高于化疗前(P0.05),Zn含量显著低于化疗前(P0.05),P含量略低于化疗前(P0.05)。结论血清Ca、P、Mg、Zn含量随着临床治疗效果所变化,可作为检测化疗效果的有效反应因子,在疗效判定方面具有一定的参考价值。 相似文献
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Mindaugas iau
iulis Nanna Ahlsten Alexander P. Pulis David J. Procter 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(26):8871-8875
A transition metal‐free one‐pot stereoselective approach to substituted (E,Z)‐1,3‐dienes was developed by using an interrupted Pummerer reaction/ligand‐coupling strategy. Readily available benzothiophene S‐oxides, which can be conveniently prepared by oxidation of the parent benzothiophenes, undergo Pummerer coupling with styrenes. Reaction of the resultant sulfonium salts with alkyllithium/magnesium reagents generates underexploited hypervalent sulfurane intermediates that undergo selective ligand coupling, resulting in dismantling of the benzothiophene motif and the formation of decorated (E,Z)‐1,3‐dienes. 相似文献
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Ghalamkari Safoura Khosravian Farinaz Mianesaz Hamidreza Kazemi Mohammad Behjati Mohaddeseh Hakimian Sayyed Mohammadreza Salehi Mansoor 《Applied biochemistry and biotechnology》2019,187(3):975-983
Applied Biochemistry and Biotechnology - One of the most common somatic mutations in breast cancer is found in PIK3CA with a prevalence rate of 18–45%. Different variants of this gene are... 相似文献
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Jerry D. Monroe Ermek Belekov Ali Oguz Er Michael E. Smith 《Photochemistry and photobiology》2019,95(6):1473-1481
Photodynamic therapy (PDT) is a field with many applications including chemotherapy. Graphene quantum dots (GQDs) exhibit a variety of unique properties and can be used in PDT to generate singlet oxygen that destroys pathogenic bacteria and cancer cells. The PDT agent, methylene blue (MB), like GQDs, has been successfully exploited to destroy bacteria and cancer cells by increasing reactive oxygen species generation. Recently, combinations of GQDs and MB have been shown to destroy pathogenic bacteria via increased singlet oxygen generation. Here, we performed a spectrophotometric assay to detect and measure the uptake of GQDs, MB and several GQD‐MB combinations in MCF‐7 breast cancer cells. Then, we used a cell counting method to evaluate the cytotoxicity of GQDs, MB and a 1:1 GQD:MB preparation. Singlet oxygen generation in cells was then detected and measured using singlet oxygen sensor green. The dye, H2DCFDA, was used to measure reactive oxygen species production. We found that GQD and MB uptake into MCF‐7 cells occurred, but that MB, followed by 1:1 GQD:MB, caused superior cytotoxicity and singlet oxygen and reactive oxygen species generation. Our results suggest that methylene blue's effect against MCF‐7 cells is not potentiated by GQDs, either in light or dark conditions. 相似文献
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Yi‐Hung Chen Mai Sun Paul Knochel 《Angewandte Chemie (International ed. in English)》2009,48(12):2236-2239
Sensitive functional groups such as COR, CHO, or CH2OH can be present in benzylic indium reagents prepared by the direct insertion of indium in the presence of LiCl. These reagents undergo palladium‐catalyzed cross‐coupling reactions in the presence of a protic cosolvent after activation with iPrMgCl⋅LiCl (see scheme). Remarkable chemoselectivities are achieved by using various electrophiles containing NH or OH groups.
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Sunghun Lee Dr. Juneho In Jung‐Won Chang Dr. Kwanyong Seo Prof. Myung‐Hwa Jung Dr. Jinhee Kim Prof. Bongsoo Kim 《化学:亚洲杂志》2012,7(2):406-411
We report unconventional magnetotransport properties of an individual Fe1?xCoxSi nanowire. We have studied the dependence of the resistivity on the angle between the directions of the magnetization and electrical current below the Curie temperature (TC). The observed anisotropic magnetoresistance (MR) ratio is negative, thereby indicating that the conduction electrons in a minority spin band of the Fe1?xCoxSi nanowire dominantly contribute to the transport. Unlike typical ferromagnets, positive MR is observed in the overall temperature range. MR curves are linear below TC and show a quadratic form above TC, which can be explained by the change of density of states that arises as the band structures of the Fe1?xCoxSi nanowire shift under a magnetic field. The temperature dependence of the resistivity curve is sufficiently explained by the Kondo effect. The Kondo temperature of the Fe1?xCoxSi nanowire is lower than that of the bulk state due to suppression of the Kondo effect. The high single crystallinity of Fe1?xCoxSi nanowires allowed us to observe and interpret quite subtle variations in the prominent intrinsic transport properties. 相似文献
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Liu Liu Shuangyan Zhang Dr. Hu Chen Ye Lv Dr. Jun Zhu Prof. Dr. Yufen Zhao 《化学:亚洲杂志》2013,8(11):2592-2595
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Summary: Specific temperature‐responsive biodegradable hydrogels were synthesized and characterized in terms of their regulation of enzymatic accessibility based on the physical properties of the temperature‐responsive polymers. The hydrogels consist of glycidyl methacrylate‐modified dextran grafted with the poly(N‐isopropylacrylamide) (PNIPAAm) homopolymer, and cross‐linked by co‐polymerization with NIPAAm and N,N‐dimethylacrylamide (DMAAm). The coil‐globule change in the grafted poly(NIPAAm) chains and only a slight dehydration of the poly(NIPAAm‐co‐DMAAm) cross‐linkers are effective in controlling the enzymatic degradation over a specific temperature range.
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Wen Bo Han Dr. Yang Sun Ye Guo Dr. Qi Wu Dr. Hui Ming Ge Dr. Yong Chun Song Prof. Dr. Seik Weng Ng Prof. Dr. Qiang Xu Prof. Dr. Ren Xiang Tan 《化学:亚洲杂志》2013,8(12):3101-3107
The limited selection of immunosuppressants in the clinic hampers the efficient management of immune disorders such as rejections after organ transplantations. However, the search for new immunosuppressive compounds remains random and creates inevitably financial and laborious wastes. Herein, we present an immunity‐inspired discovery strategy that rationally allows an efficient identification of immunosuppressive compounds from the endophyte culture, as exemplified by the new peptide trichomide A. This compound exerts its immunosuppressive action more selectively than cyclosporin A. It was found that trichomide A decreases the expression of Bcl‐2, increases the expression of Bax, and has a small or negligible effect on the expressions of p‐Akt, CD25, and CD69. Our study strengthens the idea that the cross‐kingdom similarity in immunity among living things could provide a shorter route towards the identification of natural products valuable for the development of new immunosuppressants. 相似文献
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Murali Mohan Yallapu Meena Jaggi Subhash C. Chauhan 《Macromolecular bioscience》2010,10(10):1141-1151
A novel PCD/CUR self‐assembly approach for improved curcumin delivery to prostate cancer cells is described. The formation of PCD/CUR was confirmed using FTIR, DSC, TGA, and SEM/TEM, and their stability and solubility under physiological conditions was demonstrated. A mechanism for self‐assembly is proposed. Intracellular uptake of the self‐assemblies was studied by flow cytometry and immunofluorescence microscopy. The therapeutic efficacy was determined by cell proliferation and colony formation assays using C4‐2, DU145 and PC3 prostate cancer cells. The results suggest that the PCD/CUR formulation could be a useful system for improving curcumin delivery and its therapeutic efficacy in prostate cancer.
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A Comparative Study of Cellular Uptake and Subcellular Localization of Doxorubicin Loaded in Self‐Assemblies of Amphiphilic Copolymers with Pendant Dendron by MDA‐MB‐231 Human Breast Cancer Cells 下载免费PDF全文
Geetha Viswanathan Yu‐Hsuan Hsu Siew Hui Voon Toyoko Imae Ampornphan Siriviriyanun Hong Boon Lee Lik Voon Kiew Lip Yong Chung Shin‐ichi Yusa 《Macromolecular bioscience》2016,16(6):882-895
Previously synthesized amphiphilic diblock copolymers with pendant dendron moieties have been investigated for their potential use as drug carriers to improve the delivery of an anticancer drug to human breast cancer cells. Diblock copolymer (P71D3)‐based micelles effectively encapsulate the doxorubicin (DOX) with a high drug‐loading capacity (≈95%, 104 DOX molecules per micelle), which is approximately double the amount of drug loaded into the diblock copolymer (P296D1) vesicles. DOX released from the resultant P71D3/DOX micelles is approximately 1.3‐fold more abundant, at a tumoral acidic pH of 5.5 compared with a pH of 7.4. The P71D3/DOX micelles also enhance drug potency in breast cancer MDA‐MB‐231 cells due to their higher intracellular uptake, by approximately twofold, compared with the vesicular nanocarrier, and free DOX. Micellar nanocarriers are taken up by lysosomes via energy‐dependent processes, followed by the release of DOX into the cytoplasm and subsequent translocation into the nucleus, where it exert its cytotoxic effect.