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A Spectrophotometric Study on the Host-Guest Complexation of β-Cyclodextrin with 3-Indolyl Acetate in Dilute Aqueous Solution by Determining Solubility of Guest Substance
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作者 De Zhi SUN Jian CHENI Wei Min LU and Xiao Ming ZHENG(Institute of Catalysis. Xixi Xiaoqu. Zhejiang University. Hangzho 310028Department of Chemistry, Liaocheng Teachers College. Liaocheng, 252000 Shandong.Department of Chemistry, Zhejiang Normal Univers 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第5期411-414,共4页
3-Indolyl acetate can be soluhilized in dilute aqueous solution of beta cy clodextrin. dueto the formation of host-guest complex through hydrophobic interaction between the indolyl groupand the inside cave of the cycl... 3-Indolyl acetate can be soluhilized in dilute aqueous solution of beta cy clodextrin. dueto the formation of host-guest complex through hydrophobic interaction between the indolyl groupand the inside cave of the cyclodextrin molecule. The thermodynamic pararneters of thecomplexing process can be estimated utilizing the spectrophotometric data. 展开更多
关键词 Β-CYCLODEXTRIN 3-indolyl acetate host-guest complex
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Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries
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作者 Yaqing Zhou Fan Sun +4 位作者 Gunahua Lin Sandrine Zanna Antoine Seyeux Philippe Marcus Jolanta´Swiatowska 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期825-839,共15页
Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environ... Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and cost-effectiveness.However,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low utilization.Thus,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is reported.The resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid addition.The thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries. 展开更多
关键词 acetic acid additive in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film Surface characterization Hydrogen evolution
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Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction
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作者 Cheng-Jin Ai Ling-Juan Chen +2 位作者 Li-Xuan Guo Ya-Ping Wang Zi-Yi Zhao 《World Journal of Stem Cells》 SCIE 2024年第4期444-458,共15页
BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against... BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against conventional therapies.Gossypol acetic acid(GAA),which is extracted from the seeds of cotton plants,exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2.AIM To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism.METHODS In this study,LSCs were magnetically sorted from AML cell lines and the CD34+CD38-population was obtained.The expression of leucine-rich pentatricopeptide repeat-containing protein(LRPPRC)and forkhead box M1(FOXM1)was evaluated in LSCs,and the effects of GAA on malignancies and mitochondrial RESULTS LRPPRC was found to be upregulated,and GAA inhibited cell proliferation by degrading LRPPRC.GAA induced LRPPRC degradation and inhibited the activation of interleukin 6(IL-6)/janus kinase(JAK)1/signal transducer and activator of transcription(STAT)3 signaling,enhancing chemosensitivity in LSCs against conventional chemotherapies,including L-Asparaginase,Dexamethasone,and cytarabine.GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC.Furthermore,GAA induced reactive oxygen species accumulation,disturbed mitochondrial homeostasis,and caused mitochondrial dysfunction.By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC,GAA resulted in the elimination of LSCs.Meanwhile,GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage.CONCLUSION Taken together,the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML. 展开更多
关键词 Leukemia stem cells Gossypol acetic acid Reactive oxygen species Mitochondrial dysfunction Interleukin 6/janus kinase 1/signal transducer and activator of transcription 3 signaling
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Diurnal emission of herbivore-induced(Z)-3-hexenyl acetate and allo-ocimene activates sweet potato defense responses to sweet potato weevils
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作者 XIAO Yang-yang QIAN Jia-jia +4 位作者 HOU Xing-liang ZENG Lan-ting LIU Xu MEI Guo-guo LIAO Yin-yin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第6期1782-1796,共15页
The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However,... The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However, no safe and effective methods have been found to protect sweet potato from this pest. Herbivore-induced plant volatiles(HIPVs)promote various defensive bioactivities, but their formation and the defense mechanisms in sweet potato have not been investigated. To identify the defensive HIPVs in sweet potato, the release dynamics of volatiles was monitored.The biosynthetic pathways and regulatory factors of the candidate HIPVs were revealed via stable isotope tracing and analyses at the transcriptional and metabolic levels. Finally, the anti-insect activities and the defense mechanisms of the gaseous candidates were evaluated. The production of(Z)-3-hexenyl acetate(z3HAC) and allo-ocimene was induced by sweet potato weevil feeding, with a distinct circadian rhythm. Ipomoea batatas ocimene synthase(IbOS) is first reported here as a key gene in allo-ocimene synthesis. Insect-induced wounding promoted the production of the substrate,(Z)-3-hexenol, and upregulated the expression of IbOS, which resulted in higher contents of z3HAC and allo-ocimene,respectively. Gaseous z3HAC and allo-ocimene primed nearby plants to defend themselves against sweet potato weevils. These results provide important data regarding the formation, regulation, and signal transduction mechanisms of defensive volatiles in sweet potato, with potential implications for improving sweet potato weevil management strategies. 展开更多
关键词 sweet potato (Z)-3-hexenyl acetate allo-ocimene defense signaling
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Scale-up of biomass conversion using 1-ethyl-3-methylimidazolium acetate as the solvent 被引量:3
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作者 Ling Liang Jipeng Yan +4 位作者 Qian He Tina Luong Todd R.Pray Blake A.Simmons Ning Sun 《Green Energy & Environment》 SCIE CSCD 2019年第4期432-438,共7页
This scale-up study demonstrated the feasibility of an ionic liquid(IL)pretreatment process at 40 kg scale,using the IL 1-ethyl-3-methylimidazolium acetate([C2C1Im][OAc])as the solvent.The pretreatment was followed by... This scale-up study demonstrated the feasibility of an ionic liquid(IL)pretreatment process at 40 kg scale,using the IL 1-ethyl-3-methylimidazolium acetate([C2C1Im][OAc])as the solvent.The pretreatment was followed by enzymatic hydrolysis through which the process efficiency for biomass conversion to monomeric sugars was determined.The results show that 43 wt%of switchgrass was dissolved in IL after 2 h of pretreatment at 160℃ with 15 wt%solid loading.A 120 h enzymatic hydrolysis of the pretreated switchgrass results in 96%glucan and 98%xylan conversion.[C2C1Im][OAc]pretreatment has been successfully scaled up to 40 kg with improved sugar titers and yields relative to bench scale(6 kg).The mass flow of the overall process was established and the major scale-up challenges of the process were identified. 展开更多
关键词 IONIC liquid 1-Ethyl-3-methylimidazolium acetate PRETREATMENT Scale up ENZYME
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Al_(2)(SO_(4))_(3)催化热解油转化生产酯类燃料
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作者 罗丹 夏淑倩 +4 位作者 郭丽潇 韩建荣 蒋可为 郝全爱 李娇 《河北科技大学学报》 CAS 北大核心 2024年第3期283-289,共7页
酸类、糖类等不稳定组分的存在是制约热解油直接用作生物燃料的主要因素。为了解决此问题,提出采用Al_(2)(SO_(4))_(3)催化剂将这些不稳定成分酯化为燃料类化合物的途径。首先,分别以单模型化合物左旋葡萄糖或乙酸为原料,考察各种金属... 酸类、糖类等不稳定组分的存在是制约热解油直接用作生物燃料的主要因素。为了解决此问题,提出采用Al_(2)(SO_(4))_(3)催化剂将这些不稳定成分酯化为燃料类化合物的途径。首先,分别以单模型化合物左旋葡萄糖或乙酸为原料,考察各种金属硫酸盐催化其转化制备乙酰丙酸乙酯或乙酸乙酯的能力,筛选出催化性能最好的催化剂;其次,以左旋葡萄糖和乙酸的模型混合物为原料,探究Al_(2)(SO_(4))_(3)催化同时转化制备酯类的最佳反应条件;最后,以真实热解油为原料,验证Al_(2)(SO_(4))_(3)在最佳反应条件下催化酯化的可行性。结果表明,酯化后热解油中大部分酸、糖、醛消失,同时产生大量的酯和缩醛,酯类和缩醛类占改性热解油总色谱面积的39.5%。Al_(2)(SO_(4))_(3)能有效将热解油中的酸类、糖类等不稳定组分酯化为燃料类化合物,可为热解油转化制备生物燃料提供借鉴。 展开更多
关键词 催化化学 热解油 乙酰丙酸乙酯 乙酸乙酯 Al_(2)(SO_(4))_(3)
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Alisol B acetate induces apoptosis of SGC7901 cells via mitochondrial and phosphatidylinositol 3-kinases/Akt signaling pathways 被引量:6
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作者 Yong-Hong Xu Li-Jie Zhao Yan Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第23期2870-2877,共8页
AIM: To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action. METHODS: The cytotoxic effect of alisol B acetate on SGC7901 cells was measu... AIM: To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action. METHODS: The cytotoxic effect of alisol B acetate on SGC7901 cells was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Phase-contrast and electron microscopy were used to observe the morphological changes. Cell cycle and mitochondrial transmembrane potential (△Ψm) were determined by flow cytometry. Western blotting was used to detect the expression of apoptosis-regulated gene Bcl-2, Bax, Apaf-1, caspase-3, caspase-9, Akt, P-Akt and phosphatidylinositol 3-kinases (PI3K). RESULTS: Alisol B acetate inhibited the proliferation of SGC7901 cell line in a time-and dose-dependent manner. PI staining showed that alisol B acetate can change the cell cycle distribution of SGC7901, increase the proportion of cells in G0-G1 phase and decrease the proportion of S phase cells and G2-M phase cells. Alisol B acetate at a concentration of 30 μmol/L induced apoptosis after 24, 48 and 72 h incubation, with occurrence rates of apoptotic cells of 4.36%, 14.42% and 21.16%, respectively. Phase-contrast and electron microscopy revealed that the nuclear fragmentation and chromosomal condensed, cells shrank and attachment loss appeared in the SGC7901 treated with alisol B acetate. Apoptosis of SGC7901cells was associated with cell cycle arrest, caspase-3 and caspase-9 activation, loss of mitochondrial membrane potential and up-regulation of the ratio of Bax/Bcl-2 and inhibition of the PI3K/Akt. CONCLUSION: Alisol B acetate exhibits an antiproliferative effect in SGC7901 cells by inducing apoptosis. Apoptosis of SGC7901 cells involves mitochondria-caspase and PI3K/Akt dependent pathways. 展开更多
关键词 信号通路 线粒体 乙酸酯 磷脂 细胞 诱导 泽泻
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乙酸改性γ-Al_(2)O_(3)高效去除痕量PCl_(3)的研究
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作者 黄鹏兵 袁威 +3 位作者 王雪莹 王悦 张建树 邓人攀 《石河子大学学报(自然科学版)》 CAS 北大核心 2024年第2期133-139,共7页
在多晶硅生产过程中,为了不影响产品性能,必须将杂质PCl_(3)的含量降低到ppb的水平,然而,这目前仍旧是一个巨大的挑战。本研究提出了一种可高效去除痕量PC13的方法,即利用乙酸改性γ-Al_(2)O_(3)作为吸附剂,其可去除ppb级别的PCl_(3),... 在多晶硅生产过程中,为了不影响产品性能,必须将杂质PCl_(3)的含量降低到ppb的水平,然而,这目前仍旧是一个巨大的挑战。本研究提出了一种可高效去除痕量PC13的方法,即利用乙酸改性γ-Al_(2)O_(3)作为吸附剂,其可去除ppb级别的PCl_(3),去除率高达84.2%。Boehm滴定实验表明,改性后的γ-Al_(2)O_(3)表面羧基含量大幅增加,从而增加了吸附PCl_(3)的活性位点,使其对PCl_(3)的吸附性能显著提升。表征分析和DFT模拟计算表明,乙酸与γ-Al_(2)O_(3)主要是通过γ-Al_(2)O_(3)中的羟基H和乙酸中的羰基O形成氢键而相互作用的;除了物理吸附外,γ-Al_(2)O_(3)中的Al与PCl_(3)中的Cl,以及乙酸中的羰基O与PCl_(3)中的P之间还可通过电荷转移相互作用。连续五次循环实验表明,该吸附剂在低温下具有优异的再生性能。本研究开发的吸附剂由于其高效、易于再生和低成本等特点,在去除痕量PCl_(3)方面具有潜在的应用前景。 展开更多
关键词 γ-Al_(2)O_(3) 乙酸 吸附 痕量PCl_(3) 多晶硅
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顺-3-己烯醇乙酸酯对大蜡螟的驱避作用
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作者 连雅琴 付童 +4 位作者 李一然 刘巧 周令霞 门丽娜 张志伟 《山西农业科学》 2024年第1期131-136,共6页
利用植物挥发物监测和调控害虫行为已逐渐成为害虫绿色防控的重要途径。顺-3-己烯醇乙酸酯广泛存在于瓜果及绿色植物的叶片中,具有环境友好、无残留的优点。大蜡螟是养蜂产业中常见的害虫,严重影响蜂产业和蜜蜂资源保护。为生产中应用顺... 利用植物挥发物监测和调控害虫行为已逐渐成为害虫绿色防控的重要途径。顺-3-己烯醇乙酸酯广泛存在于瓜果及绿色植物的叶片中,具有环境友好、无残留的优点。大蜡螟是养蜂产业中常见的害虫,严重影响蜂产业和蜜蜂资源保护。为生产中应用顺-3-己烯醇乙酸酯调控大蜡螟的行为控制其对蜂群的危害提供依据,为开发新型昆虫行为调控剂以及大蜡螟的绿色防控提供支持,利用Y-型嗅觉仪研究大蜡螟不同虫态的个体对不同浓度、同一浓度不同剂量顺-3-己烯醇乙酸酯的行为趋性。结果表明,大蜡螟幼虫对顺-3-己烯醇乙酸酯表现出显著的负趋性,浓度为0.5 mol/L时,大蜡螟幼虫总选择率为79.33%,并表现为极显著的负趋性;雄成虫对顺-3-己烯醇乙酸酯的选择率为8.33%,具有显著的负趋性;不同剂量的顺-3-己烯醇乙酸酯对大蜡螟成虫的选择行为影响不显著,但对幼虫均具有明显的驱避效果。 展开更多
关键词 顺-3-己烯醇乙酸酯 行为趋性 Y-型嗅觉仪 大蜡螟 驱避
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Optimization of technological conditions for one-pot synthesis of (S)-α-cyano-3-phenoxybenzyl acetate in organic media 被引量:1
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作者 章亭洲 杨立荣 朱自强 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第3期175-181,共7页
Optically active form of α-cyano-3-phenoxybenzyl (CPB) alcohol, building block of pyrethroid insecticides, was synthesized as its acetate by the combination of anion-exchange resin (D301)-catalyzed transcyanation bet... Optically active form of α-cyano-3-phenoxybenzyl (CPB) alcohol, building block of pyrethroid insecticides, was synthesized as its acetate by the combination of anion-exchange resin (D301)-catalyzed transcyanation between m-phenoxybenzaldehyde (m-PBA) and acetone cyanohydrin (AC), and lipase (from Alcaligenes sp.)-catalyzed enantioselective transesterification of the resulting cyanohydrin with vinyl acetate. Through optimizing technological conditions, the catalyzing efficiency was improved considerably compared to methods previously reported. Concentrations of CPB acetate were determined by gas chromatograph. The enantio excess (e.e.) values of CPB acetate were measured by NMR (nuclear magnetic resonance) method. Effects of solvents and temperatures on this reaction were studied. Cyclohexane was shown to be the best solvent among the three tested solvents. 55 °C was the optimal temperature for higher degree of conversion. External diffusion limitation was excluded by raising the rotational speed to 220 r/min. However, internal diffusion could not be ignored, since the catalyst (lipase) was an immobilized enzyme and its particle dimension was not made small enough. The reaction rate was substantially accelerated when the reactant (m-PBA) concentration was as high as 249 mmol/L, but decreased when the initial concentration of m-PBA reached to 277 mmol/L. It was also found that the catalyzing capability of recovered lipase was high enough to use several batches. Study of the mole ratio of AC to m-PBA showed that 2:1 was the best choice. The strategy of adding base catalyst D301 was found to be an important factor in improving the degree of conversion of the reaction from 20% to 80%. The highest degree of conversion of the reaction has reached up to 80%. 展开更多
关键词 有机物 生物合成法 (S)-α-氰基-3-苯氧基苯甲基醋酸盐 氰醇 化学结构
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新型醛糖还原酶抑制1-乙酰基-1H-吲哚-3-乙酸酯的合成及其抑制活性
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作者 李卓玲 杨威龙 +4 位作者 赵珊 王淑红 李臣 王志兵 修志明 《合成化学》 CAS 2024年第2期124-127,共4页
醛糖还原酶抑制剂(ARIs)抑制多元醇途径的醛糖还原酶是治疗糖尿病并发症的重要策略。以2-氯苯甲酸为起始原料,在碱性条件下经铜催化,与甘氨酸反应生成氯代邻羧基苯基甘氨酸,再与乙酸酐反应,生成N-乙酰基邻羧基苯甲酸。然后在吡啶催化下... 醛糖还原酶抑制剂(ARIs)抑制多元醇途径的醛糖还原酶是治疗糖尿病并发症的重要策略。以2-氯苯甲酸为起始原料,在碱性条件下经铜催化,与甘氨酸反应生成氯代邻羧基苯基甘氨酸,再与乙酸酐反应,生成N-乙酰基邻羧基苯甲酸。然后在吡啶催化下合环,生成1-乙酰基-^(1)H-吲哚-3-乙酸酯(AIA),总收率为79.0%,纯度为99.0%。通过^(1)H NMR、^(13)C NMR和MS(ESI)对其结构进行表征,并对该化合物的的醛糖还原酶抑制活性进行测定,IC 50=9.4×10^(-2)μM。 展开更多
关键词 糖尿病并发症 醛糖还原酶抑制剂 合成 抑制活性 1-乙酰基-1 H-吲哚-3-乙酸酯
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Theoretical Studies on the Aminolysis of Ester: Effects of the Catalysis and Substituent to the Reaction of Methyl Indole-3-acetate with Ammonia 被引量:1
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作者 张亮 陈容 梁国明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第6期855-866,共12页
A comprehensive exploration of the aminolysis mechanism for methyl indole-3-acetate with ammonia is carried out by employing the B3 LYP/6-311++G(d,p), M06-2 X/6-311++G(d,p) and MP2/6-311++G(d,p)//M06-2 X/6-311++G(d,p)... A comprehensive exploration of the aminolysis mechanism for methyl indole-3-acetate with ammonia is carried out by employing the B3 LYP/6-311++G(d,p), M06-2 X/6-311++G(d,p) and MP2/6-311++G(d,p)//M06-2 X/6-311++G(d,p) levels. Two alterative reaction channels of the concerted and addition/elimination stepwise processes including the uncatalyzed, base-catalyzed reactions are taken into consideration. Subsequently, the substituent effects and solvent effects in methanol are also evaluated at the M06-2 X/6-311++G(d,p) level. The calculated results indicate that the calculated values of M06-2 X level are quite close to those of MP2, the stepwise pathway has more advantages to the concerted one for all of the reaction processes and the catalyst facilitates the proton migration and decreases the energy barriers as well. It is shown that the most preferred mechanism is the based-catalyzed stepwise process, the substituent of NH2 group slightly accelerates all the aminolysis reaction processes, and the solvent effect does not remarkably change the mechanism of the reaction. 展开更多
关键词 AMINOLYSIS METHYL indole-3-acetate mechanism catalytic EFFECT SUBSTITUENT EFFECT
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蜂胶黄酮Pinobanksin-3-acetate对人胃癌SGC-7901细胞中HSPA6、GEM、FOS、RGS2、GADD45G基因表达的影响 被引量:1
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作者 阿依努尔.玉苏普 胡尼其古丽.阿巴克 +2 位作者 其曼古丽.吐尔洪 吾热娅提.克维尔 依米提.热合慢 《天然产物研究与开发》 CAS CSCD 北大核心 2017年第3期477-481,共5页
考察蜂胶黄酮Pinobanksin-3-acetate(PB3A)对人胃癌SGC-7901细胞中相关基因表达的影响,用不同浓度(0、40、80μg/mL)的PB3A处理胃癌SGC-7901细胞24 h后提取总RNA,采用实时荧光定量PCR技术检测GEM、GADD45G、HSPA6、RGS2及FOS基因mRNA表... 考察蜂胶黄酮Pinobanksin-3-acetate(PB3A)对人胃癌SGC-7901细胞中相关基因表达的影响,用不同浓度(0、40、80μg/mL)的PB3A处理胃癌SGC-7901细胞24 h后提取总RNA,采用实时荧光定量PCR技术检测GEM、GADD45G、HSPA6、RGS2及FOS基因mRNA表达量,各个基因的DMSO对照组与40、80μg/mLPB3A处理组的ΔCt值进行比较。结果显示40μg/mLPB3A处理组与对照组比较HSPA6、GEM、FOS基因mRNA表达量明显提高(P<0.05),差异倍数分别为0.12(HSPA6)、2.17(GEM)、2.1(FOS),反而GADD45G、RGS2基因ΔCt无显著变化(P>0.05);80μg/mLPB3A处理组与对照组比较HSPA6基因mRNA表达量明显提高(P<0.05),其差异倍数为0.5,而其他基因mRNA表达水平无显著变化(P>0.05)。上述试验结果说明40μg/mLPB3A对人胃癌SGC-7901细胞中基因表达的影响比较明显;PB3A可能通过上调HSPA6、GEM、FOS基因表达而影响人胃癌SGC-7901细胞增殖。该研究结果为PB3A肿瘤治疗中的分子调控机制提供基础资料。 展开更多
关键词 PB3A 胃癌SGC-7901细胞 基因表达
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KBrO_3/MoO_3:An efficient reagent system for the oxidative deprotection of semicarbazones,1,1-diacetates and acetals
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作者 Farhad Shirini Zahra Neyestani Masoumeh Abedini 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期514-518,共5页
Semicarbazones, 1,1-diacetates and acetals are efficiently converted to their corresponding carbonyl compounds using synergistic effect between KBrO3 and MoO3 in refluxing CH3CN-H2O in good to high yields.
关键词 SEMICARBAZONES 1 1-Diacetates acetALS KBRO3 MOO3
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Antioxidant and anti-caspase 3 effect of chitosan-Pinus merkusii extract nanoparticle against lead acetate-induced testicular toxicity in rat
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作者 Sri Agus Sudjarwo Chairul Anwar +2 位作者 Giftania Wardani Koerniasari Eraiko Koerniasari 《Asian pacific Journal of Reproduction》 2019年第1期13-19,共7页
Objective: To investigate the antioxidant and anti-caspase 3 effect of chitosan-Pinus merkusii extract nanoparticle on lead acetate-induced toxicity in rat testis. Methods: Chitosan-Pinus merkusii nanoparticles were i... Objective: To investigate the antioxidant and anti-caspase 3 effect of chitosan-Pinus merkusii extract nanoparticle on lead acetate-induced toxicity in rat testis. Methods: Chitosan-Pinus merkusii nanoparticles were identified by dynamic light scattering and scanning electron microscope. The male rats were divided into control group (rats were given with distilled water);lead acetate group [rats were injected with lead acetate 20 mg/kg body weight (BW) i.p.], and the treatment group (rats were given the chitosan-Pinus merkusii nanoparticle 150 mg;300 mg;600 mg/kg BW orally and were injected with lead acetate 20 mg/kg BW). The testis tissues were collected to evaluate the malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), histological evaluations of testis damage, and the caspase 3 mRNA expression was measured by reverse transcription-polymerase chain reaction. Results: The dynamic light scattering showed that the size of chitosan-Pinus merkusii nanoparticle was (530.2±38.2) nm. The scanning electron microscope images of the chitosan-Pinus merkusii nanoparticles showed an irregular shape, and the morphology surface showed the rough surface. The treatment with lead acetate resulted in significantly increasing MDA level and caspase 3 mRNA expression, and significantly decreasing level of SOD and GPx when compared with control group. The treatment with the chitosan-Pinus merkusii nanoparticle 600 mg/kg BW but not 150 and 300 mg/kg BW significantly decreased the MDA levels, caspase 3 mRNA expression, and also increased level of SOD and GPx when compared with lead acetate group. The lead acetate induced loss of the normal structure of testicular cells and necrosis, whereas treatment with chitosan-Pinus merkusii nanoparticle inhibited testicular cell necrosis. Conclusions: It can be concluded that chitosan-Pinus merkusii nanoparticle protects rat testis from oxidative damage and apoptosis caused by lead acetate, through increasing antioxidant and inhibiting caspase 3 expression. 展开更多
关键词 Chitosan-Pinus merkusii NANOPARTICLE Lead acetate ANTIOXIDANT CASPASE 3
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Synthesis,Characterization,X-ray Crystal Structure and Safener Activity of Chiral 2-(3-Methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)-2-oxoethyl Acetate
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作者 叶非 程阳 +2 位作者 吴世龙 孙长迎 付颖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第11期1694-1699,共6页
The new title compound, chiral 2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)- 2-oxoethyl acetate, has been synthesized via reduction, cyclization and acylation reaction. The structure of the product has been conf... The new title compound, chiral 2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)- 2-oxoethyl acetate, has been synthesized via reduction, cyclization and acylation reaction. The structure of the product has been confirmed by IR, 1H NMR, 13C NMR, LC-MS (ESI) and single-crystal X-ray diffraction. (R)-2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)-2-oxoethyl acetate crystallizes in monoclinic, space group P21/c with a = 11.867(2), b = 8.4087(2), c = 14.325(6) A^°, β = 117.59(2)°, Z = 4, V = 1266.9(6) A^°3, Dc = 1.307 g/cm^3, F(000) = 528, μ(MoKα) = 0.097 mm-1, R = 0.0453 and wR = 0.1237; (S)-2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)-2-oxoethyl acetate belongs to the triclinic system, space group P with a = 8.2647(17), b = 8.7034(17), c = 9.5479(19) A^°, α = 105.33(3), β = 100.95(3), γ = 105.14(3)°, Z = 2, V = 614.1(2) A^°3, Dc = 1.348 g/cm^3, F(000) = 264, μ(MoKα) = 0.10 mm-1, R = 0.0613 and wR = 0.1037. Both of the molecules prefer to form crystal packing through C–H…O hydrogen bonds. 展开更多
关键词 synthesis single crystal CHIRAL 2-(3-methyl-2 3-dihydrobenzo[b][1 4]oxazin-4-yl)-2-oxoethyl acetate
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活体检测吲哚-3-乙酸的电化学传感器研究
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作者 闫路程 李爱学 吴瑞刚 《传感器与微系统》 CSCD 北大核心 2024年第5期47-50,54,共5页
吲哚-3-乙酸(IAA)作为一种重要的植物激素,在植物生长发育的整个过程中起着至关重要的作用。本文根据植物活体检测的实际需要,发展了适合植物茎秆活体检测的四阵列电极及用于植物果实活体检测的六阵列电极,通过一步法在铂(Pt)丝工作电... 吲哚-3-乙酸(IAA)作为一种重要的植物激素,在植物生长发育的整个过程中起着至关重要的作用。本文根据植物活体检测的实际需要,发展了适合植物茎秆活体检测的四阵列电极及用于植物果实活体检测的六阵列电极,通过一步法在铂(Pt)丝工作电极上沉积铂纳米颗粒(PtNPs)和还原氧化石墨烯(rGO)纳米复合膜,从而增强催化效果,提高生物传感器的灵敏度。实验结果表明,所研制的传感器在IAA浓度0.1~200μmol/L范围内,具有良好的线性关系,相关系数为R~2=0.986,检测限为0.01μmol/L(S/N=3)。进一步利用所制备的传感器活体检测了黄瓜茎秆和黄瓜果实(CF)内的IAA含量,表明该传感器在植物生理状态的活体检测中具有重要应用前景。 展开更多
关键词 活体 吲哚-3-乙酸 电化学 传感器
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Impact of Ionic Liquid 1-Ethyl-3-Methylimidazolium Acetate Mediated Extraction on Lignin Features
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作者 Idi Guga Audu Isabelle Ziegler-Devin +5 位作者 Heiko Winter Martina Bremer Anton Hoffmann Steffen Fischer Marie-Pierre Laborie Nicolas Brosse 《Green and Sustainable Chemistry》 2017年第2期114-140,共27页
This study aims at investigating the impact of ionic liquid extraction on lignin structure by studying the mechanism of lignin depolymerization in 1-ethyl-3-methylimidazolium acetate EMIM[OAc]) and comparing it with t... This study aims at investigating the impact of ionic liquid extraction on lignin structure by studying the mechanism of lignin depolymerization in 1-ethyl-3-methylimidazolium acetate EMIM[OAc]) and comparing it with that of organosolv and milled wood methods. Ionic liquid mediated lignin (ILL) using EMIM[OAc]), ethanol organosolv lignin (EOL) and milled wood lignin (MWL) were isolated from Typha capensis (TC) and subjected to several analytical characterizations. Experimental data shows that ILL exhibited a relatively lower degree of condensation, lower aromatic C-C structures and a higher aliphatic OH with values of 0.42/Ar, 1.94/Ar and 1.33/Ar moieties compared with EOL values of 0.92/Ar, 2.22/Ar and 0.51/Ar moieties respectively. The ILL was depolymerized under mild conditions giving relatively higher β-aryl ether linkages content, higher molecular mass, and exhibited closer structures and reactivity to native lignin than EOL. These insights on TC lignin depolymerization in EMIM[OAc]) acetate may contribute to better value-addition of lignocellulosic biomass. 展开更多
关键词 1-Ethyl-3-Methylimidazolium acetate IONIC Liquid LIGNIN Ethanol ORGANOSOLV LIGNIN LIGNIN DEPOLYMERIZATION Milled Wood LIGNIN
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Anti-tumor Activities of Novel Estrogen Compound 17aα-D-Homo-Ethynylestradiol-3-Acetate
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作者 周则卫 唐卫生 +3 位作者 沈秀 韩英 王晓雪 张良安 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2008年第1期17-20,共4页
Objective: To study the anti-tumor activities of novel estrogen compound 17a α-D-homo-ethynylestradiol-3-acetate in vitro and in vivo. Methods: In vitro anti-tumor activity was assayed in adenoma cells A549 and hum... Objective: To study the anti-tumor activities of novel estrogen compound 17a α-D-homo-ethynylestradiol-3-acetate in vitro and in vivo. Methods: In vitro anti-tumor activity was assayed in adenoma cells A549 and human liver cancer cells Bel-7402 using MTT method, and half-inhibitory concentration (IC50) were observed. In vivo the pulmonary adenoma LA795 cells was selected and the conventional assay method of anti-tumor activity was employed. 5, 7.5, 10 mg/kg of 17a α-D-homo-ethynylestradiol-3-acetate was administered by i.p., and tumor-inhibitory rate, thymus and spleen indexes, bone marrow cells (BMC) were observed. Results: IC50 of 17a α-D-homo-ethynylestradiol-3-acetate in vitro for A549 and Bel-7402 cells were 12.28 μg/ml and 17.79 μg/ml, respectively. In vivo the highest tumor-inhibitory rates for LA795 was 60.0% (P〈0.01). The drug had hardly any side-effect in spleen indexes, thymus indexes, and BMC compared with control mice. Nevertheless, compared with the positive control drug cyclophosphamide (CY), thymus and spleen indexes, BMC showed obvious differences (P〈0.01). Conclusion: 17a α-D-homo-ethynylestradiol-3-acetate has obvious anti-tumor activities in vitro and in vivo with low side-effect, thus worth further investigation. 展开更多
关键词 17a α-D-homo-ethynylestradioi-3-acetate ESTROGEN ANTI-TUMOR PHARMACOLOGY
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小红参乙酸乙酯提取物调控PI3K/AKT/GSK3-β通路对心肌缺血再灌注损伤大鼠雌激素的影响
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作者 张国庆 周艳华 +1 位作者 王仙琪 王佳佳 《河北医药》 CAS 2024年第4期501-505,共5页
目的研究小红参乙酸乙酯提取物通过调控磷脂酰肌醇3-激酶(phosphatidylinositol-3-OH kinase,PI3K)/蛋白激酶B(protein kinase B,Akt)/糖原合成酶激酶3-β(glycogen synthase kinase 3-β,GSK3-β)通路对心肌缺血再灌注损伤大鼠雌激素... 目的研究小红参乙酸乙酯提取物通过调控磷脂酰肌醇3-激酶(phosphatidylinositol-3-OH kinase,PI3K)/蛋白激酶B(protein kinase B,Akt)/糖原合成酶激酶3-β(glycogen synthase kinase 3-β,GSK3-β)通路对心肌缺血再灌注损伤大鼠雌激素的影响。方法选取SPF级SD雌性大鼠50只,空白组10只,建模中死亡10只,随机分为模型组、低剂量组、高剂量组,每组10只。对照组不做任何处理,模型组、低剂量组、高剂量组进行心肌缺血再灌注损伤模型建模,建模成功后模型组不做任何处理,低剂量组、高剂量组分别给予小红参乙酸乙酯提取物灌胃,其剂量分别为56.7 mg/kg、280 mg/kg。观察大鼠心肌损伤[肌钙蛋白I(CTnI)、肌酸激酶同工酶(CK-MB)]、氧化应激[丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)]、一氧化氮(NO)、内皮-氧化氮合酶(eNOS)含量、性激素、PI3K/AKT/GSK3-β信号通路表达量情况。结果与空白组比较,模型组、低剂量组、高剂量组cTnI、CK-MB、MDA、E2水平均升高(P<0.05),SOD、GSH-Px、NO、eNOS水平、PI3K、AKT、GSK3-β表达均降低(P<0.05);与模型组比较,低剂量组、高剂量组cTnI、CK-MB、MDA、E2水平均降低(P<0.05),SOD、GSH-PxNO、eNOS水平、PI3K、AKT、GSK3-β表达均升高(P<0.05);与低剂量组比较,高剂量组cTnI、CK-MBE2水平均降低(P<0.05),SOD、GSH-PxNO、eNOS水平、PI3K、AKT、GSK3-β表达均升高(P<0.05)。结论小红参乙酸乙酯提取物能对心肌缺血再灌注损伤大鼠能心肌损伤情况进行改善,抑制氧化应激状态,恢复雌激素水平,通过调节PI3K/AKT/GSK3-β通路能够反映出对心肌缺血再灌注损伤的干预效果。 展开更多
关键词 心肌缺血再灌注 小红参乙酸乙酯 雌激素 磷脂酰肌醇3-激酶/蛋白激酶B/糖原合成酶激酶3
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