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Salsolinol as an RNA m~6A methylation inducer mediates dopaminergic neuronal death by regulating YAP1 and autophagy
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作者 Jianan Wang Yuanyuan Ran +5 位作者 Zihan Li Tianyuan Zhao Fangfang Zhang Juan Wang Zongjian Liu Xuechai Chen 《Neural Regeneration Research》 SCIE CAS 2025年第3期887-899,共13页
Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environme... Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environmental toxin that causes Parkinson's disease.However,the mechanism by which Sal mediates dopaminergic neuronal death remains unclear.In this study,we found that Sal significantly enhanced the global level of N~6-methyladenosine(m~6A)RNA methylation in PC12 cells,mainly by inducing the downregulation of the expression of m~6A demethylases fat mass and obesity-associated protein(FTO)and alk B homolog 5(ALKBH5).RNA sequencing analysis showed that Sal downregulated the Hippo signaling pathway.The m~6A reader YTH domain-containing family protein 2(YTHDF2)promoted the degradation of m~6A-containing Yes-associated protein 1(YAP1)mRNA,which is a downstream key effector in the Hippo signaling pathway.Additionally,downregulation of YAP1 promoted autophagy,indicating that the mutual regulation between YAP1 and autophagy can lead to neurotoxicity.These findings reveal the role of Sal on m~6A RNA methylation and suggest that Sal may act as an RNA methylation inducer mediating dopaminergic neuronal death through YAP1 and autophagy.Our results provide greater insights into the neurotoxic effects of catechol isoquinolines compared with other studies and may be a reference for assessing the involvement of RNA methylation in the pathogenesis of Parkinson's disease. 展开更多
关键词 ALKBH5 AUTOPHAGY FTO Hippo pathway m~6A Parkinson's disease RNA methylation SALSOLINOL YAP1 YTHDF2
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Effects of Promoter Region 5’CpG Island Demethylation on the Biological Behavior of Human Colorectal Cancer RKO Cells in Vitro 被引量:1
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作者 方晓明 郑树 +4 位作者 姜朝晖 彭佳萍 孙立峰 方旭东 姚宁 《Chinese Journal of Clinical Oncology》 CSCD 2008年第1期10-15,共6页
OBJECTIVE To explore the relationship between the methylation status of the promoter 5'CpG island region and the biological behavior of human colorectal cancer RKO cells in vitro. METHODS RKO cells were treated with ... OBJECTIVE To explore the relationship between the methylation status of the promoter 5'CpG island region and the biological behavior of human colorectal cancer RKO cells in vitro. METHODS RKO cells were treated with a selective DNA methyltransferase inhibitor-5-aza-2'-deoxycytidine (5-aza-CdR) for 72 h. Methylationspecific PCR (MSP), T-A cloning and DNA sequence analysis were used to determinate the 5'CpG island methylation status of the p16/CDKN2 tumor suppressor gene. Cell growth, morphological changes and apoptosis were analyzed by the MTT assay, flow cytometry, fluorescence staining and electron microscopy. RESULTS The 5'CpG island of the p16/CDKN2 tumor suppressor gene in RKO cells was a typically hypermethylated. The DNA methyltransferase inhibitor (5-Aza-CdR) effectively reversed the hypermethylation status of the promoter region. With demethylation, RKO cell growth was suppressed, the cells doubling times were prolonged (P〈0.01) and apoptosis was induced, which showed a relationship. CONCLUSION A selective DNA methyltransferase (DNMT) inhibitor can inhibit proliferation by demethylation in 5'CpG islands, and may be a potential new therapy target for colorectal cancer. 展开更多
关键词 methylATION colorectal cancer 5-AZA-CDR PROLIFERATION apoptosis.
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下调METTL5通过Wnt/β-catenin信号通路抑制三阴乳腺癌细胞增殖、迁移与侵袭 被引量:1
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作者 吴坤琳 严乾壹 +2 位作者 王德星 缪秀英 张惠灏 《中国药理学通报》 CAS CSCD 北大核心 2024年第2期285-291,共7页
目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的s... 目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的shRNA(shRNA-METTL5)转染TNBC细胞后,用CCK-8、集落形成、伤口愈合以及Transwell实验分别检测细胞增殖活性、迁移与侵袭,Western blot检测Wnt/β-catenin信号关键蛋白的表达。构建异种移植瘤模型,验证敲降METTL5对TNBC细胞在体内生长以及Wnt/β-catenin信号活性的影响。结果METTL5在TNBC肿瘤组织和细胞系中表达上调(P<0.01)。敲降METTL5可抑制TNBC细胞的增殖、迁移和侵袭并降低了Wnt/β-catenin信号分子β-catenin、细胞周期蛋白(Cyclin)D1、基质金属蛋白酶(MMP)-2和MMP-7的表达(均P<0.01)。体内实验显示,敲降METTL5减缓了移植瘤生长和Wnt/β-catenin信号活性。结论敲降METTL5能抑制TNBC细胞的增殖、迁移与侵袭,其作用可能与抑制Wnt/β-catenin信号通路有关。 展开更多
关键词 三阴乳腺癌 甲基转移酶5 m6A甲基化 WNT/Β-CATENIN 增殖 迁移 侵袭
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蛋白精氨酸甲基转移酶5表达与非M3型急性髓系白血病疗效关系的临床观察
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作者 代萍 陈艳梅 张艳梅 《临床肿瘤学杂志》 CAS 2024年第6期566-570,共5页
目的讨论蛋白精氨酸甲基转移酶5(PRMT5)与急性髓系白血病(AML)患者低甲基化药物(HMA)治疗敏感性的关系。方法通过GEPIA和TCGA数据库分析AML患者PRMT5表达及其与AML患者生存的关系。收集2020年1月至2023年10月收治的81例AML患者,包括50例... 目的讨论蛋白精氨酸甲基转移酶5(PRMT5)与急性髓系白血病(AML)患者低甲基化药物(HMA)治疗敏感性的关系。方法通过GEPIA和TCGA数据库分析AML患者PRMT5表达及其与AML患者生存的关系。收集2020年1月至2023年10月收治的81例AML患者,包括50例非M3型患者和31例M3型患者。采用实时荧光定量PCR(qPCR)检测骨髓样本中PRMT5表达。采用全基因组重亚硫酸盐测序(WGBS)检测基因组甲基化水平。结果TCGA数据库中AML患者PRMT5表达显著高于健康对照人群(P<0.01);PRMT5高表达组患者总生存期更短(P=0.036)。进一步分析TCGA数据库,巩固期给予HMA后,PRMT5表达对无事件生存率(EFS)和OS的有明显影响(P<0.010)。81例新诊断AML患者PRMT5表达显著高于23例健康志愿者[3.25(1.69,5.16)vs.1.00(0.72,1.35),P<0.001]。非M3型AML患者PRMT5表达高于M3型患者[4.51(2.05,7.25)vs.2.01(1.53,3.35),(P<0.001)]。在非M3型AML患者中,PRMT5高表达与BM原始细胞百分率以及不良基因突变和高危患者比例更高有关(P<0.05)。与未接受HMA治疗患者比较,接受HMA治疗的PRMT5高表达非M3型AML患者CR率显著增加(P=0.003)。通过WGBS测序,PRMT5高表达组CpG岛甲基化比率以及转录起始位点、转录终止位点CpG岛甲基化比率高于PRMT5低表达组(P<0.001)。结论在非M3型AML患者中PRMT5高表达,PRMT5高表达预示着更多非M3型AML患者从HMA治疗中获益。PRMT5可能是评估肿瘤甲基化富集和预测疾病预后的潜在生物标志物。 展开更多
关键词 急性髓系白血病 蛋白精氨酸甲基转移酶5 基因组甲基化 低甲基化药物
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Methylation of GATA-4 and GATA-5 and development of sporadic gastric carcinomas 被引量:9
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作者 Yoshimitsu Akiyama 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第10期1201-1208,共8页
AIM:To understand the implication of GATA-4 and GATA-5 methylation in gastric carcinogenesis.METHODS: Methylation status of GATA-4 and GATA-5 CpG islands in human gastric mucosa samples, including normal gastric biops... AIM:To understand the implication of GATA-4 and GATA-5 methylation in gastric carcinogenesis.METHODS: Methylation status of GATA-4 and GATA-5 CpG islands in human gastric mucosa samples, including normal gastric biopsies from 45 outpatients, gastric dysplasia [low-grade gastric intraepithelial neoplasia (GIN), n = 30; indefinite, n = 77], and 80 paired spo- radic gastric carcinomas (SGC) as well as the adjacent non-neoplastic gastric tissues was analyzed by methylation specific polymerase chain reaction (MSP) and confirmed by denatured high performance liquid chromatography (DHPLC). Immunohistochemical staining was used to detect protein expression. The correlation between GATA-4 and GATA-5 methylation and clinicopathological characteristics of patients including Helicobacter pylori (H. pylori) infection was analyzed.RESULTS:GATA-4 and GATA-5 methylation was frequently observed in SGCs (53.8% and 61.3%, respectively) and their corresponding normal tissues (41.3% and 46.3%) by MSP. The result of MSP was consistent with that of DHPLC. Loss of both GATA-4 and GATA-5 proteins was associated with their methylation in SGCs (P = 0.01). Moreover, a high frequency of GATA-4 and GATA-5 methylation was found in both gastric low-grade GIN (57.1% and 69.0%) and indefinite for dysplasia (42.9% and 46.7%), respectively. However, GATA-4 and GATA-5 methylation was detected only in 4/32 (12.5%) and 3/39 (7.7%) of normal gastric biopsies. GATA-4 methylation in both normal gastric mucosa and low-grade GIN was also significantly associated with H. pylori infection (P=0.023 and 0.027, two-sides).CONCLUSION: Epigenetic inactivation of GATA-4 (and GATA-5) by methylation of CpG islands is an early freuent event during gastric carcinogenesis and is significantly correlated with H. pylori infection. 展开更多
关键词 DYSPLASIA Gastric carcinoma GATA-4 GATA-5 Helicobacter pylori methylATION
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Regulation of demethylation and re-expression of RASSF1A gene in gastric cancer cell lines by combined treatment of 5-Aza-CdR and NaB 被引量:21
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作者 Wen-Jing Shen Dong-Qiu Dai +1 位作者 Yue Teng Hong-Bo Liu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第4期595-600,共6页
AIM: To investigate the changes of methylation state and expression of RASSF1A gene in human gastric cancer cell lines SGC7901 and BGC823 which were treated in vitro with demethlylating agent 5-Aza-CdR in combination... AIM: To investigate the changes of methylation state and expression of RASSF1A gene in human gastric cancer cell lines SGC7901 and BGC823 which were treated in vitro with demethlylating agent 5-Aza-CdR in combination with histone deacetylase inhibitor NaB. METHODS: After SGC7901 and BGC823 cells were treated with 5-Aza-CdR and/or NaB, the methylation state of RASSFIA gene was detected by methylationspecific PCR, and the changes in expression of mRNA and protein level of RASSFIA gene were observed by RT-PCR and Western-blotting before and after drug treatment. RESULTS: Hypermethylation was detected in the promoter region of RASSF1A gene in both SGC7901 and BGC823 cells, and there was no expression of this gene at both mRNA and protein level. After treatment with 5-Aza-CdR, demethylation occurred in the promoter region of RASSFIA gene, which subsequently induced re-expression of this gene. The treatment with NaB alone showed no effect on the methylation state and expression of RASSFIA gene. The combined treatment of 5-Aza-CdR and NaB induced complete demethylation of RASSFIA gene, leading to a significantly higher reexpression of the mRNA and protein of RASSFIA than those treated with 5-Aza-CdR alone (P 〈 0.05). CONCLUSION: Hypermethylation in the promoter region is related to inactivation of RASSFIA gene in human gastric cancer cell lines SGC7901 and BGC823, while demethlylating agent 5-Aza-CdR can reverse the methylation state of RASSF1A gene and induce itsre-expression. Histone deacetylase inhibitor NaB had a synergistic effect with 5-Aza-CdR in both demethylation and gene transcriptional regulation. 展开更多
关键词 5-AZA-CDR NAB RASSFIA gene Gastric cancer DNA methylation
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PRMT5 regulates Golgi apparatus structure through methylation of the golgin GM130 被引量:16
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作者 Zhongwei Zhou Xiaotian Sun +10 位作者 Zhenhua Zou Litao Sun Tao Zhang Shaoshi Guo Ya Wen Lin Liu Yi Wang Jun Qin Lei Li Weimin Gong Shilai Bao 《Cell Research》 SCIE CAS CSCD 2010年第9期1023-1033,共11页
Maintenance of the Golgi apparatus (GA) structure and function depends on Golgi matrix proteins. The posttranslational modification of Golgi proteins such as phosphorylation of members of the golgin and GRASP famili... Maintenance of the Golgi apparatus (GA) structure and function depends on Golgi matrix proteins. The posttranslational modification of Golgi proteins such as phosphorylation of members of the golgin and GRASP families is important for determining Golgi architecture. Some Golgi proteins including golgin-84 are also known to be methylated, but the function of golgin methylation remains unclear. Here, we show that the protein arginine methyltransferase 5 (PRMT5) localizes to the GA and forms complexes with several components involved in GA ribbon formation and vesicle tethering. PRMT5 interacts with the golgin GM130, and depletion of PRMT5 causes defects in Golgi ribbon formation. Furthermore, PRMT5 methylates N-terminal arginines in GM130, and such arginine methylation appears critical for GA ribbon formation. Our findings reveal a molecular mechanism by which PRMT5-dependent arginine methylation of GM130 controls the maintenance of GA architecture. 展开更多
关键词 Arginine methylation GM130 Golgi structure PRMT5
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5-methyl-1H-benzotriazole as potential corrosion inhibitor for electrochemical-mechanical planarization of copper 被引量:1
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作者 边燕飞 翟文杰 朱宝全 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2431-2438,共8页
According to the electrochemical analysis, the corrosion inhibition efficiency of 5-methyl-lH-benzotriazole (m-BTA) is higher than that of benzotrizaole (BTA). The inhibition capability of the m-BTA passive film f... According to the electrochemical analysis, the corrosion inhibition efficiency of 5-methyl-lH-benzotriazole (m-BTA) is higher than that of benzotrizaole (BTA). The inhibition capability of the m-BTA passive film formed in hydroxyethylidenediphosphonic acid (HEDP) electrolyte containing both m-BTA and chloride ions is superior to that formed in m-BTA-alone electrolyte, even at a high anodic potential. The results of electrical impedance spectroscopy, nano-scratch experiments and energy dispersive analysis of X-ray (EDAX) indicate that the enhancement of m-BTA inhibition capability may be due to the increasing thickness of passive film. Furthermore, X-ray photoelectron spectrometry (XPS) analysis indicates that the increase in passive film thickness can be attributed to the incorporation of C1 into the m-BTA passive film and the formation of [Cu(I)CI(rn-BTA)], polymer film on Cu surface. Therefore, the introduction of C1- into m-BTA-containing HEDP electrolyte is effective to enhance the passivation capability of m-BTA passive film, thus extending the operating potential window. 展开更多
关键词 electrochemical-mechanical planarization 5-methyl-lH-benzotriazole corrosion inhibitor chloride ion
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Methylation of 2-Methylnaphthalene with Methanol over NH_4 F and Pt Modified HZSM-5 Catalysts 被引量:7
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作者 赵亮 郭新闻 +2 位作者 刘民 王祥生 宋春山 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第5期742-749,共8页
Shape-selective methylation of 2-methylnaphthalene (2-MN) was carried out over NH 4 F and Pt modified HZSM-5 (SiO 2 /Al 2 O 3 = 83) catalysts in a fixed-bed down-flow reactor using methanol as methylating agent and 1,... Shape-selective methylation of 2-methylnaphthalene (2-MN) was carried out over NH 4 F and Pt modified HZSM-5 (SiO 2 /Al 2 O 3 = 83) catalysts in a fixed-bed down-flow reactor using methanol as methylating agent and 1,3,5-trimethylbenzene (1,3,5-TMB) as a solvent. Pt promoted HZSM-5 catalysts showed low concentration of coke-like polycondensed aromatics, NH 4 F modification decreased non-shape-selective acid sites. After Pt and NH 4 F co-modification, both conversion of 2-MN and selectivity to 2,6-DMN were improved. 6%NH 4 F/0.5%Pt/HZSM-5 catalyst exhibited 13.8% of 2-MN conversion with 6.2% of 2,6-DMN yield after 7 h time on stream (TOS), and 2,6-/2,7-DMN ratio of 1.7 after 10 h of TOS. 展开更多
关键词 2-methylNAPHTHALENE methylATION HZSM-5 2 6-dimethylnaphthalene NH 4 F/Pt/HZSM-5
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Re-expression of RASSF1A by 5-Aza-CdR Induced Demethylation of the Promoter Region in Human Biliary Tract Carcinoma Cells 被引量:3
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作者 左石 陈勇军 +2 位作者 徐立宁 唐启彬 邹声泉 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第3期281-284,共4页
Hypermethylation of the promoter region is an important mean for the transcriptional repression of a number of cancer-associated genes, and over-expression and/or increased activity of DNA methyltransferase are consid... Hypermethylation of the promoter region is an important mean for the transcriptional repression of a number of cancer-associated genes, and over-expression and/or increased activity of DNA methyltransferase are considered to be the main cause of promoter hypermethylation. In order to further explore the epigenetic mechanism of tumor suppressor gene RASSF1A inactivation, 5-aza-2’-deoxycytidine (5-Aza-CdR), a DNA methyltransferase inhibitor, was used to treat the human biliary tract carcinoma cell line QBC-939 at the concentration of 5 μmol/L for 24 h in this study. Af- ter the chemical intervention with 5-Aza-CdR, the methylation status in the promoter region of RASSF1A gene was detected by methylation specific PCR (MS-PCR), and the expression alteration of RASSF1A mRNA and protein were observed by RT-PCR and Western Blot respectively. Following the treatment with 5-Aza-CdR, methylaiton status in the promoter region of RASSF1A gene was re- versed from methylation to unmethylation. A 280 bp DNA band which represented RASS1FA expres- sion at transcriptional level and a 40 kDa (1kDa=0.9921 ku) protein band which represented RASSF1A expression at protein level were detected by RT-PCR and Western Blot respectively in the experimental group cells and there were no corresponding bands in the control group cells. The ex- perimental results suggest that 5-Aza-CdR can induce demethylation in the promoter region of RASSF1A. It can also reverse epigenetic transcriptional silencing caused by DNA methylation and induce the re-expression of RASSF1A in QBC-939. This study also suggest that the mechanism of RASSF1A inactivation is very closely related to the methylation of the promoter region, which may provide a new epigenetic understanding for tumor related gene inactivation and the pathogenesis of biliary tract carcinoma. 展开更多
关键词 5-aza-2'-deoxycytidine RASS1A gene biliary tract carcinoma DNA methylation gene expressio
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Promoting Xylene Production in Benzene Methylation using Hierarchically Porous ZSM-5 Derived from a Modified Dry-gel Route 被引量:4
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作者 邓威 何暄 +5 位作者 张超 高云逸 朱学栋 朱卡克 霍启升 周志杰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第8期921-929,共9页
Methylation of benzene is an alternative low-cost route to produce xylenes, but selectivity to xylene remains low over conventional zeolitic catalysts. In this work, a combined dry-gel-conversion and steam-assisted- c... Methylation of benzene is an alternative low-cost route to produce xylenes, but selectivity to xylene remains low over conventional zeolitic catalysts. In this work, a combined dry-gel-conversion and steam-assisted- crystallization method is used to synthesize hierarchically porous zeolite ZSM-5 with varied Si/AI malar ratios. X-ray diffraction (XRD), N2 physisorption, NH3-temperature programmed desorption (TPD), scanning electronic microscopic (SEM) measurement and Fourier transform infrared (FT-IR) are employed to characterize the struc- ture and acidity of both hierarchically porous zeolites and their conventional counterparts. The method is found to be applicable to ZSM-5 with molar ratios of Si/A1 from 20 to 180. The ZSM-5 zeolites are used as catalysts for benzene methylation at 460 ℃ to investigate the effect of additional porosity and Si/A1 ratios. At low Si/AI ratios, the benzene conversions over conventional and hierarchical ZSM-5 are close, and selectivity to toluene is high over hierarchical ZSM-5. It is found that hierarchical porosity markedly enhances the utility of zeolite and the se- lectivity towards xylenes via improved mass transport at higher Si/Al ratios. Under an optimized hierarchical ZSM-5 catalvst, xvlene selectivity reaches 34.9% at a Si/AI ratio of 180. 展开更多
关键词 Hierarchical zeolite BENZENE METHANOL methylATION ZSM-5 Process intensification
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Effect of Acidity on Methylation of Benzene with Methanol Catalyzed by HZSM-5:A DFT Study 被引量:3
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作者 Wei Pifeng Fu Guangbin +3 位作者 Mu Shanliang Gao Jichao Wen Zhenhao Zhu Xuedong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第2期21-27,共7页
Different acidic HZSM-5 zeolites were constructed by doping with Al,Ga,or In.The effect of acidity on the adsorption of methylbenzenes and the reaction energy barriers for the methylation of benzene with methanol cata... Different acidic HZSM-5 zeolites were constructed by doping with Al,Ga,or In.The effect of acidity on the adsorption of methylbenzenes and the reaction energy barriers for the methylation of benzene with methanol catalyzed by HZSM-5 zeolite were investigated by using the density functional theory.The results show that acidity exhibits less effect in the adsorption of methylbenzenes,while linear relationships are observed between the acidity and reaction energy barriers.As the acidity increases,the reaction energy barrier decreases linearly,and the stepwise pathway becomes dominant in strong acidity environment,while weak acidity is conducive to the concerted pathway.The calculation results could contribute to understanding the relationship between the acidity and the zeolite-catalyzed alkylation reaction of methylbenzenes. 展开更多
关键词 BENZENE METHANOL methylATION ACIDITY HZSM-5
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Synthesis,Crystal Structure and Fungicidal Activity of(E)-2-[(4-tert-Butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol 被引量:2
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作者 胡艾希 曹高 +2 位作者 马颍绮 张建宇 欧晓明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1235-1239,共5页
The title compound (E)-2-[(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crys... The title compound (E)-2-[(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 5.9362(8), b = 11.5070(15), c = 29.460(4)A, β= 97.326(3)°, V = 1995.9(5) A^3, Z = 4, F(000) = 808, C22H24N2O2S, Mr= 380.49, De= 1.266 g/cm^3, S = 1.031,μ = 0.181 mm^-1, the final R = 0.0474 and wR = 0.1441 for 4327 observed reflections (I 〉 2σ(I)). Intramolecular O-H…N hydrogen bond is observed in the crystal. The preliminary bioassay showed that the title compound exhibits 95% inhibition rate against Rhizoctonia solani at the test concentration of 500 mg/L. 展开更多
关键词 crystal structure SYNTHESIS fungicidal activity (E)-2- [(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol
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Toluene methylation with syngas to para‐xylene by bifunctional ZnZrO_(x)‐HZSM‐5 catalysts 被引量:2
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作者 Xiaoqin Han Jiachang Zuo +1 位作者 Danlu Wen Youzhu Yuan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第4期1156-1164,共9页
Toluene methylation with methanol on H‐ZSM‐5(Z5)zeolite for the directional transformation of toluene to xylene has been industrialized.However,great challenges remain because of the high energy barrier of methanol ... Toluene methylation with methanol on H‐ZSM‐5(Z5)zeolite for the directional transformation of toluene to xylene has been industrialized.However,great challenges remain because of the high energy barrier of methanol deprotonation to the methoxy group,the side reaction of methanol to olefins,coke formation,and the deactivation of zeolites.Herein,we report the toluene methylation coupled with CO hydrogenation to showcase an enhancement in para‐xylene(PX)selectivity by employing a bifunctional catalyst composed of ZnZrO_(x)(ZZO)and modified Z5.The results showed that a PX selectivity of up to 81.8%in xylene and xylene selectivity of 64.8%in hydrocarbons at 10.3%toluene conversion can be realized over the bifunctional catalyst on a fixed‐bed reactor.The selectivity of gaseous hydrocarbons decreased to 10.9%,and approximately half of that was observed in methanol reagent route where the PX selectivity in xylene was 38.8%.We observed that the acid strength,the quantity ratio of Brönsted and Lewis acid sites,and the pore size of zeolites were essential for the PX selectivity.The investigation of the H_(2)/D_(2) kinetic isotope effect revealed that the newborn methyl group in xylene resulted from the hydrogenation of CO rather than toluene disproportionation.Furthermore,the catalyst showed no evident deactivation within the 100 h stability test.The findings offer a promising route for the production of value‐added PX with high selectivity via toluene methylation coupled with syngas conversion. 展开更多
关键词 Toluene methylation Syngas conversion Para‐xylene Bifunctional catalyst ZnZrO_(x)‐ZSM‐5
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Investigation of the coupled reaction of methyl acetate and n-hexane over HZSM-5 被引量:1
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作者 Kuo Yang Jinzhe Li +1 位作者 Xiao Zhang Zhongmin Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第12期1960-1970,共11页
The coupled reaction of methyl acetate and n‐hexane was carried out over a HZSM‐5 catalyst.In addition to a thermal coupling effect,systematic variations in the product distribution were also observed in the coupled... The coupled reaction of methyl acetate and n‐hexane was carried out over a HZSM‐5 catalyst.In addition to a thermal coupling effect,systematic variations in the product distribution were also observed in the coupled system.The bezene‐toluene‐xylene(BTX)selectivity was remarkably improved while the H2,CO,and CO2 selectivity decreased.Rapid deactivation of the catalyst was observed,caused by the extremely high reactivity of methyl acetate,which was alleviated after adding n‐hexane.These results indicated that a coupling effect exists in this system.A detailed pathway for the coupled system is suggested based on the analysis of the surface species,carbonaceous species deposited on the catalyst,as well as the product selectivity changes.The good match between the"hydrogen deficiency"of methyl acetate and the"hydrogen richness"of n‐hexane is consistent with the observed coupling effect. 展开更多
关键词 methyl acetate n‐Hexane Coupled reaction HZSM‐5
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Dissolution Properties of 2-(Dinitromethylene)-5-methyl-1,3-diazacyclopentane in Dimethyl Sulfoxide and N-Methyl Pyrrolidone 被引量:2
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作者 XIAO Li-bai XING Xiao-ling +4 位作者 ZHAO Feng-qi XU Kang-zheng YAO Er-gang TAN Yi HAO Hai-xia 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期743-746,共4页
The molar enthalpies of dissolution for 2-(dinitromethylene)-5-methyl-1,3-diazacyclopentane(DNMDZ) in dimethyl sulfoxide(DMSO) and N-methyl pyrrolidone(NMP) were measured using an RD496-2000 Calvet microcalori... The molar enthalpies of dissolution for 2-(dinitromethylene)-5-methyl-1,3-diazacyclopentane(DNMDZ) in dimethyl sulfoxide(DMSO) and N-methyl pyrrolidone(NMP) were measured using an RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure.Empirical formulae for the calculation of the molar enthalpies of dissolution(Δ diss H) were obtained from the experimental data of the dissolution processes of DNMDZ in DMSO or NMP.The relationships between the rate constant(k) and the molality(b) and between the reaction order(n) and the molality(b) were determined.The corresponding kinetic equations describing the two dissolution processes were dα/dt=10^-2.16(1-α) ^1.01 for the dissolution of DNMDZ in DMSO,and dα/dt=10^-2.02(1-α)^ 0.85 for the dissolution of DNMDZ in NMP,respectively. 展开更多
关键词 2-(Dinitromethylene)-5-methyl-1 3-diazacyclopentane DISSOLUTION Kinetics DImethylSULFOXIDE N-methyl pyrrolidone
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Synthesis and Crystal Structure of a Co(Ⅱ) Complex with Taurine-5-methyl-2-hydroxyisophthalaldehyde Schiff Bases [Co(C_(13)H_(16)N_2O_7S_2)(H_2O)_3]_2·H_2O 被引量:2
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作者 QIN Xiu-Ying JIANG Yi-Min +1 位作者 ZHANG Shu-Hua MO Qian-Qun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期205-209,共5页
The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the ... The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the complex belongs to the triclinic system, space group P1, with a = 11.197(4), b = 13.309(5), c = 14.486(5) ]A, a = 78.827(13),β = 70.547(11), γ = 81.058(13)°, Mr = 996.77, S = 1.08, V= 1987.2(13) A3, Z = 2, Dc = 1.666 g/cm3, F(000) = 1032,μ = 1.131 mm^-1, R = 0.0633 and wR = 0.1293. According to the structural analysis, the Co( Ⅱ ) ion adopts a slightly distorted six-coordinated octahedral geometry. One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom. Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds, thus generating an infinite chain constructed by hydrogen bonds. 展开更多
关键词 cobalt(Ⅱ) complex taurine-5-methyl-2-hydroxyisophthalaldehydes crystal structure
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Synthesis, Crystal Structure and Antitumor Activity of 2-(3-Methyl-5-(methylthio)-4H-1,2,4-triazol-4-yl)isoindoline-1,3-dione 被引量:6
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作者 赵培亮 胡孟金 +2 位作者 段安娜 孙晓敏 游文玮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期359-364,共6页
The title compound 2-(3-methyl-5-(methylthio)-4H-1,2,4-triazol-4-yl)isoindoline- 1,3-dione (C12H10NaO2S, Mr= 274.30) has been synthesized by a three-step procedure including the cyclization, hydrazinolysis and s... The title compound 2-(3-methyl-5-(methylthio)-4H-1,2,4-triazol-4-yl)isoindoline- 1,3-dione (C12H10NaO2S, Mr= 274.30) has been synthesized by a three-step procedure including the cyclization, hydrazinolysis and substitution reactions, and its crystal structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2/c with a = 12.264(3), b = 14.646(3), c = 14.349(4) A,β = 91.69(3)°,μ = 0.255 mm1, Mr = 274.30, V = 2576.2(10) A3, Z =8, Dc = 1.414 g/cm3, F(000) = 1136, R = 0.0487 and wR = 0.1329 for 4048 observed reflections with I 〉 2σ(I). In addition, the preliminary bioassay suggested that the title compound 6 exhibits relatively good antitumor activity against HT-29 and MCF-7. 展开更多
关键词 2-(3-methyl-5-(methylthio)-4H-1 2 4-triazol-4-yl)isoindoline-l 3-dione synthesis
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Extraction Behavior of Rare Earths with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 Using Solid-liquid Extraction Technique 被引量:2
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作者 高锦章 潘仲巍 +2 位作者 杜新贞 康敬万 白光弼 《Rare Metals》 SCIE EI CAS CSCD 1993年第3期198-202,共5页
The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib- rium... The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib- rium extraction constants and pH_(1/2) values of solid-liquid extraction are higher than those of normal liquid-liquid extraction.The extraction efficiency tends to maximum when the ratio of phases is 1:1.When the extraction temperature is higher than the melting point of paraffin and the extraction time is over 10 min,the extraction efficiency keeps constant.Moreover,the relationship among separation factor,equilibrium extrac- tion constant,pH_(1/2) value and atomic number was obtained.The mechanism of solid-liquid extraction is analogous to that of liquid-liquid extraction. 展开更多
关键词 Solid-liquid extraction Rare earths 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5
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The First Two-dimensional Supramolecular Network Constructed by Na(Ⅰ) with 2-Methylimidazole-4,5-dicarboxylate Building Blocks 被引量:2
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作者 涂勇刚 熊志强 +3 位作者 宋秀英 聂旭亮 温世和 刘光斌 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第12期1770-1774,共5页
The title complex [Na(H2MIA-)(H2O)](1,H3MIA = 2-methyl-1H-imidazole-4,5-dicarboxylic acid) has been synthesized by hydrothermal synthesis and structurally characterized by X-ray crystallography.Compound 1 crysta... The title complex [Na(H2MIA-)(H2O)](1,H3MIA = 2-methyl-1H-imidazole-4,5-dicarboxylic acid) has been synthesized by hydrothermal synthesis and structurally characterized by X-ray crystallography.Compound 1 crystallizes in orthorhombic,space group ibam with a = 14.4737(19),b = 17.553(2),c = 6.5285(9),V = 1658.6(4) 3,C6H7N2NaO5,Mr = 210.12,Z = 8,Dc = 1.675 g/cm3,F(000) = 864,μ = 0.188 mm-1,λ(MoKα) = 0.071073 ,R = 0.0383 and wR = 0.0987 for 1046 observed reflections(I 2σ(I)).In the structure of 1,each coordination water coordinates with two Na(I) ions at the same time and links the neighboring Na(I) ions to form a one-dimensional Na(I)-water chain.Each H2MIA-ligand links the neighboring Na(I) of Na(I)-water chain to form a novel two-dimensional supramolecular network.The 2-D network is stabilized by O-H…N hydrogen bonds and π-π interaction.The 2D network is further linked via O-H…O hydrogen bonds to yield a three-dimensional framework. 展开更多
关键词 NA 2-methyl-1H-imidazole-4 5-dicarboxylic acid hydrothermal synthesis crystal structure
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