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A Rapid and Convenient Synthesis of Acylals from Aldehydes and Acetic Anhydrides Catalyzed by SnCl_4/SiO_2 被引量:4
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作者 Yi Qun LI Li Hui CHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第7期565-568,共4页
A variety of aldehydes were converted into acylals in excellent yields with acetic anhydride in the presence of a catalytic amount of tin (IV) chloride supported on silica gel at room temperature.
关键词 acylalS tin (IV) chloride supported on silica gel
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A Mild and Efficient Method for the Synthesis of Acylals from Aromatic Aldehydes and Their Deprotections Catalyzed by Synthetic Phosphates under Solvent-Free Conditions
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作者 Fathallaah Bazi Bahija Mounir +1 位作者 Mohammed Hamza Said Sebti 《Green and Sustainable Chemistry》 2018年第4期334-344,共11页
An efficient and clean preparation of acylals from aromatic aldehydes in the presence of synthetic phosphates (flourapatite and hydroxyapatite doped with ZnCl2 and ZnBr2) and acetic anhydride was achieved easily in hi... An efficient and clean preparation of acylals from aromatic aldehydes in the presence of synthetic phosphates (flourapatite and hydroxyapatite doped with ZnCl2 and ZnBr2) and acetic anhydride was achieved easily in high yields (86% - 97%) at room temperature under solvent-free conditions. Deprotection of the resulting acylals has also been attained by using the same catalysts under microwave irradiation. This method consistently has advantage of excellent yields (82% - 96%) and a short reaction time (3 - 4 min). 展开更多
关键词 SYNTHETIC PHOSPHATES Clean Process acylalS Protection DEPROTECTION
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Microwave-assisted,facile,rapid and solvent-free one pot two-component synthesis of some special acylals 被引量:5
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作者 Yu-Heng Ma Gang Wu +3 位作者 Nan Jiang Shu-Wang Ge Qian Zhou Bai-Wang Sun 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第1期81-84,共4页
A facile, rapid and solvent-flee method for the conversion of acids and dihalomethane to the corresponding methylene diesters (acylals) using microwave as activators or assistor, is reported. This method is particul... A facile, rapid and solvent-flee method for the conversion of acids and dihalomethane to the corresponding methylene diesters (acylals) using microwave as activators or assistor, is reported. This method is particularly powerful for the diesterification of carboxylic acids, which afford methylene diesters in good to excellent yields (up to 〉99%). When the intermediate is trapped, a "double successive SN2 reactions" mechanism is proved. 展开更多
关键词 Double successive SN2 reactions acylal ANILINES Methylene diester
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Low expression of fatty acid oxidation related gene ACADM indicates poor prognosis of renal clear cell carcinoma and is related to tumor immune infltration
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作者 JIECHUAN QIU TIANMIN YANG +3 位作者 YANNING SUN KAI SUN YINGKUN XU QINGHUA XIA 《Oncology Research》 SCIE 2024年第3期545-561,共17页
This research aims to identify the key fatty acid beta-oxidation(FAO)genes that are altered in kidney renal clear cell carcinoma(KIRC)and to analyze the role of these genes in KIRC The Gene Expression Omnibus(GEO)and ... This research aims to identify the key fatty acid beta-oxidation(FAO)genes that are altered in kidney renal clear cell carcinoma(KIRC)and to analyze the role of these genes in KIRC The Gene Expression Omnibus(GEO)and FAO datasets were used to identify these key genes.Wilcoxon rank sum test was used to assess the levels of acyl-CoA dehydrogenase medium chain(ACADM)between KIRC and non cancer samples.The logistic regression and Wilcoxon rank sum test were used to explore the association between ACADM and clinical features.The diagnostic performance of ACADM for KIRC was asessed using a diagnostic receiver operating ch aracteristic(ROC)curve.The co-expressed genes of ACADM were identifed in LinkedOmics database,and their function and pathway enrichment were analyzed.The correlation between ACADM expression level and immune infitration was analyzed by Gene Set Variation Analysis(GSVA)method Additionally,the proliferation,migration,and invasion abilities of KIRC cells were assessed after overexpressing ACADM.Following differential analysis and intersection,we identifed six hub genes,induding ACADM.We found that the expression level of ACADM was decreased in KIRC tissues and had a better diagnostic efect(AUC=0.916).Survival analysis suggested that patients with decreased ACADM expression had a worse prognosis.According to correlation analysis,a variety of dinical features were associated with the expression level of ACADML By analyzing the infiltration level of immune cells,we found that ACADM may be related to the enrichment of immune cells.Finally,ACADM overexpression inhibited proliferation,migration,and invasion of KIRC cells.In conclusion,our findings suggest that reduced ACADM expression in KIRC patients is indicative of poor prognosis.These results imply that ACADM may be a diagnostic and prognostic marker for individuals with KIRC,offering a reference for dinicians in diagnosis and treatment. 展开更多
关键词 Kidney renal clear cell carcinoma Acyl CoA dehydrogenase medium chain Immune infiltration Fatty acid oxidation Prognosis
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An efficient method for synthesis of acylals from aldehydes using multi-walled carbon nanotubes functionalized with phosphonic acid(MWCNTs-C-PO_3H_2)
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作者 Farzaneh Dehghani Ali Reza Sardarian Mohammad Mehdi Doroodmand 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第12期1630-1634,共5页
MWCNTs-C-PO3H2has been used as an efficient,heterogeneous and reusable nanocatalyst for synthesis of acylals from aldehydes under solvent-free conditions at room temperature.A wide range of aldehydes was studied and c... MWCNTs-C-PO3H2has been used as an efficient,heterogeneous and reusable nanocatalyst for synthesis of acylals from aldehydes under solvent-free conditions at room temperature.A wide range of aldehydes was studied and corresponding products were obtained in good to excellent yields in short reaction times.Nanocatalyst can be easily recovered by centrifuge and reused for subsequent reactions for at least five times without deterioration in catalytic activity.The major advantages of the present method are high yields,short reaction time,recyclable catalyst and solvent-free reaction conditions at room temperature. 展开更多
关键词 acylal MWCNTs-C-PO_3H_2 Heterogeneous catalyst Reusable catalyst Solvent-free condition
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Synthesis of Phenylpropanoid Glycoside Analogs 被引量:1
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作者 李树春 周静 李中军 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期14-18,共5页
The regioselective acylation of unprotected phenylethyl glucoside withcinnamoyl chloride leads to 6-OH cin-namoylated glucoside. In this manner, thirteen phenylpropanoidglycoside analogs were designed and prepared. Th... The regioselective acylation of unprotected phenylethyl glucoside withcinnamoyl chloride leads to 6-OH cin-namoylated glucoside. In this manner, thirteen phenylpropanoidglycoside analogs were designed and prepared. Their structure was confirmed by ~1H NMR and ^(13)CNMR spectra. 展开更多
关键词 medicinal chemistry regioselective acylation phenylpropanoid glycoside glycoside analogs chemical synthesis
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Hrd1转基因小鼠的构建与验证 被引量:1
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作者 杨硕 刘磊 +5 位作者 万幸 王文丰 王娟 贺恒 雷蕾 李斌 《中华实验眼科杂志》 CAS CSCD 北大核心 2015年第2期115-117,共3页
背景 内质网应激在糖尿病视网膜病变(DR)中发挥着重要作用.羟甲基戊二酰辅酶A还原酶降解蛋白1(Hrd1,又名Syvn1)作为一种内质网相关蛋白降解(ERAD)途径中的核心蛋白,能够减少内质网应激. 目的 构建Hrd1高表达小鼠,为今后研究Hrd1... 背景 内质网应激在糖尿病视网膜病变(DR)中发挥着重要作用.羟甲基戊二酰辅酶A还原酶降解蛋白1(Hrd1,又名Syvn1)作为一种内质网相关蛋白降解(ERAD)途径中的核心蛋白,能够减少内质网应激. 目的 构建Hrd1高表达小鼠,为今后研究Hrd1在DR中的作用提供动物模型. 方法 构建Hrd1系统表达重组质粒,酶切、测序后显微注射3 p1到685枚C57BL/6小鼠受精卵中,移植到代孕母鼠,得到Hrd1转基因小鼠.利用鼠尾PCR检测法鉴定F0代小鼠的基因型.得到Hrd1基因检测阳性鼠后,使其分别与野生型鼠杂交,得到F1代Hrd1转基因小鼠,取鼠尾组织,用PCR检测法再次鉴定F1代小鼠基因型. 结果 成功构建了Hrd1重组载体,重组质粒pRP.ExBi-EF1 a-Syvn1-IRES-eGFP的全序列测定结果显示,cDNA序列均正确.接受了Hrd1-pcDNA显微注射的685枚受精卵中成活598枚.将存活的受精卵移植到代孕母鼠后共产子鼠41只,获F0代子鼠8只,生理活动均良好.PCR电泳显示339 bp处阳性条带,该基因型可以传递到子代F1.结论 成功构建了Hrd1转基因小鼠. 展开更多
关键词 羟甲基戊二酰辅酶A还原酶降解蛋白1 小鼠/转基因 内质网应激 糖尿病视网膜病变 HYDROXYMETHYL glutaric ACYL COENZYME A REDUCTASE degradation protein 1
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ACYL RADICAL CYCLISATIONS 被引量:1
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作者 陈立功 孙春光 王多禄 《Transactions of Tianjin University》 EI CAS 1996年第2期71+65-70,共7页
Several phenylselenyl esters were selected as precursors of acyl radicals and synthesised by our established method. Treatment of these phenylselenyl esters with tributyltinhydride and AIBN ge... Several phenylselenyl esters were selected as precursors of acyl radicals and synthesised by our established method. Treatment of these phenylselenyl esters with tributyltinhydride and AIBN generated the corresponding acyl radicals, which were found to proceed in 5 exo trig or 6 endo trig cyclisations to afford high yields of cyclopentanones and cyclohexanones, The substitution groups on the substrates have played an important role on the regioselectivity of cyclisations. 展开更多
关键词 phenylselenyl ester acyl radical 5 exo trig process 6 endo trig process regioselectivity
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A magnetic biocatalyst based on mussel-inspired polydopamine and its acylation of dihydromyricetin 被引量:4
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作者 邓啸 曹诗林 +4 位作者 李宁 吴虹 Thomas J.Smithd 宗敏华 娄文勇 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期584-595,共12页
A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles (PD-MNPs) was prepared and characterized. The widely used Aspetyillus niger lipase (ANL) was immobilized on the PD-MNPs (ANL... A support made of mussel-inspired polydopamine-coated magnetic iron oxide nanoparticles (PD-MNPs) was prepared and characterized. The widely used Aspetyillus niger lipase (ANL) was immobilized on the PD-MNPs (ANL@PD-MNPs) with a protein loading of 138 mg/g and an activity recovery of 83.6% under optimized conditions. For the immobilization, the pH and immobilization time were investigated. The pH and thermal and storage stability of the ANL@PD-MNPs significant- ly surpassed those of free ANL. The ANL@PD-MNPs had better solvent tolerance than free ANL. The secondary structure of free ANL and ANL@PD-MNPs was analyzed by infrared spectroscopy, A kinetic study demonstrated that the ANL@PD-MNPs had enhanced enzyme-substrate affinity and high catalytic efficiency. The ANL@PD-MNPs was applied as a biocatalyst for the regioselective acylation of dihydromyricetin (DMY) in DMSO and gave a conversion of 79.3%, which was higher than that of previous reports. The ANL@PD-MNPs retained over 55% of its initial activity after 10 cycles of reuse. The ANL@PD-MNPs were readily separated from the reaction system by a magnet. The PD-MNPs is an excellent support for ANL and the resulting ANL@PD-MNPs displayed good potential for the efficient synthesis of dihydromyricetin-3-acetate by enzymatic regioselective acylation. 展开更多
关键词 Magnetic iron oxide Nanoparticle POLYDOPAMINE Aspergillus niger lipase DIHYDROMYRICETIN ACYLATION
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法国公司推出防治母猪尿道和生殖道疾病的营养方案
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作者 邹晓文 《中国动物保健》 2005年第1期28-28,共1页
母猪尿道和生殖系统的疾病是生猪饲养当中经常发生的问题,不管从经济上还是技术上,都会导致一些饲养者无法忽视的后果。在法国,根据饲养的类型不同,这类疾病所导致的损失每百头母猪高达一千五百到两千欧元。因病症出现很晚,这类疾... 母猪尿道和生殖系统的疾病是生猪饲养当中经常发生的问题,不管从经济上还是技术上,都会导致一些饲养者无法忽视的后果。在法国,根据饲养的类型不同,这类疾病所导致的损失每百头母猪高达一千五百到两千欧元。因病症出现很晚,这类疾病又很难检测,因此提高尿液的酸性程度,能够起到限制细菌生长的作用,是一种有效的预防措施。 展开更多
关键词 法国 母猪 尿道疾病 生殖道疾病 营养方案 ACYL
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Anti-oxidant and anti-inflammatory effects of hydrogenrich water alleviate ethanol-induced fatty liver in mice 被引量:14
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作者 Ching-Pin Lin Wen-Chen Chuang +1 位作者 Fung-Jou Lu Chih-Yen Chen 《World Journal of Gastroenterology》 SCIE CAS 2017年第27期4920-4934,共15页
AIM To investigate the effects of hydrogen-rich water(HRW) treatment on prevention of ethanol(Et OH)-induced early fatty liver in mice.METHODS In vitro reduction of hydrogen peroxide by HRW was determined with a chemi... AIM To investigate the effects of hydrogen-rich water(HRW) treatment on prevention of ethanol(Et OH)-induced early fatty liver in mice.METHODS In vitro reduction of hydrogen peroxide by HRW was determined with a chemiluminescence system. Female mice were randomly divided into five groups: control,Et OH,Et OH + silymarin,Et OH + HRW and Et OH + silymarin + HRW. Each group was fed a Lieber-De Carli liquid diet containing Et OH or isocaloric maltose dextrin(control diet). Silymarin was used as a positive control to compare HRW efficacy against chronic Et OH-induced hepatotoxicity. HRW was freshly prepared and given at a dosage of 1.2 m L/mouse trice daily. Blood and liver tissue were collected after chronic-binge liquid-diet feeding for 12 wk.RESULTS The in vitro study showed that HRW directly scavenged hydrogen peroxide. The in vivo study showed that HRW increased expression of acyl ghrelin,which was correlated with food intake. HRW treatment significantly reduced Et OH-induced increases in serum alanine aminotransferase,aspartate aminotransferase,triglycerol and total cholesterol levels,hepatic lipid accumulation and inflammatory cytokines,including tumor necrosis factor-alpha(TNF-α) and interleukin(IL)-6. HRW attenuated malondialdehyde level,restored glutathione depletion and increased superoxide dismutase,glutathione peroxidase and catalase activities in the liver. Moreover,HRW reduced TNF-α and IL-6 levels but increased IL-10 and IL-22 levels.CONCLUSION HRW protects against chronic Et OH-induced liver injury,possibly by inducing acyl ghrelin to suppress the pro-inflammatory cytokines TNF-α and IL-6 and induce IL-10 and IL-22,thus activating antioxidant enzymes against oxidative stress. 展开更多
关键词 Hydrogen Chronic plus binge Et OH feeding Antioxidant Protective cytokine Acyl ghrelin Female mice
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interrelationships between ghrelin, insulin and glucose homeostasis: physiological relevance 被引量:10
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作者 FranCois Chabot Alexandre Caron +1 位作者 Mathieu Laplante David H St-Pierre 《World Journal of Diabetes》 SCIE CAS 2014年第3期328-341,共14页
Ghrelin is a 28 amino acid peptide mainly derived from the oxyntic gland of the stomach. Both acylated(AG) and unacylated(UAG) forms of ghrelin are found in the circulation. Initially, AG was considered as the only bi... Ghrelin is a 28 amino acid peptide mainly derived from the oxyntic gland of the stomach. Both acylated(AG) and unacylated(UAG) forms of ghrelin are found in the circulation. Initially, AG was considered as the only bioactive form of ghrelin. However, recent advances indicate that both AG and UAG exert distinct and common effects in organisms. Soon after its discovery, ghrelin was shown to promote appetite and adiposity in animal and human models. In response to these anabolic effects, an impressive number of elements have suggested the influence of ghrelin on the regulation of metabolic functions and the development of obesityrelated disorders. However, due to the complexity ofits biochemical nature and the physiological processes it governs, some of the effects of ghrelin are still debated in the literature. Evidence suggests that ghrelin influences glucose homeostasis through the modulation of insulin secretion and insulin receptor signaling. On the other hand, insulin was also shown to influence circulating levels of ghrelin. Here, we review the relationship between ghrelin and insulin and we describe the impact of this interaction on the modulation of glucose homeostasis. 展开更多
关键词 Acylated ghrelin Unacylated ghrelin Insulin secretion β-cell functions Insulin receptor signalling Glucose homeostasis
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Tribological Performances of Fatty Acyl Amino Acids Used as Green Additives in Lubricating Oil 被引量:9
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作者 Chen Boshui Wang Jiu +3 位作者 Fang Jianhua Huang Weijiu Sun Xia Yu Ying 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2010年第3期49-53,共5页
The friction and wear characteristics of lauroyl glutamine, lauroyl glycine and lauroyl alanine, used as green additives in HVI 350 mineral lubricating oil, were evaluated on a four-ball tribotester. The morphologies ... The friction and wear characteristics of lauroyl glutamine, lauroyl glycine and lauroyl alanine, used as green additives in HVI 350 mineral lubricating oil, were evaluated on a four-ball tribotester. The morphologies and chemical species of the worn surfaces were analyzed by scanning electron microscope (SEM) and X-ray photoelectron spectroscope (XPS), respectively. The test results indicated that the three fatty acyl amino acids could effectively improve the anti-wear and friction-reducing abilities of the HVI 350 mineral oil. The improvement in anti-wear and friction-reducing abilities of the mineral oil by the related amino acids was mainly ascribed to the formation of a composite boundary lubrication film due to the adsorption of amino acids on the friction surfaces. 展开更多
关键词 fatty acyl amino acid mineral lubricating oil friction wear
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Silica gel supported AlCl_3 catalyzed Friedel-Crafts acylation of aromatic compounds 被引量:5
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作者 Kaveh Parvanak Boroujeni 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1395-1398,共4页
Silica gel supported aluminium trichloride(SiO2-AlCl3) has been shown to be a mild,efficient,and chemoseiective heterogeneous Lewis acid catalyst for the acylation of aromatic compounds with acid chlorides.The catal... Silica gel supported aluminium trichloride(SiO2-AlCl3) has been shown to be a mild,efficient,and chemoseiective heterogeneous Lewis acid catalyst for the acylation of aromatic compounds with acid chlorides.The catalyst can be reused up to five times after simple washing with ether and is stable(as a bench top catalyst). 展开更多
关键词 ACYLATION KETONES Aluminium trichloride Silica gel
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一种高效简易的聚(4-乙烯基三溴化吡啶)催化乙醇合成乙酸盐的方法(英文) 被引量:5
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作者 Maryam HAJJAMI Arash GHORBANI-CHOGHAMARANI Masoomeh NOROUZI 《催化学报》 SCIE EI CAS CSCD 北大核心 2012年第10期1661-1664,共4页
Poly(4-vinylpyridinium tribromide) is an efficient catalyst for the conversion of various alcohols to their corresponding acetate derivatives with acetic anhydride.This method has some advantages such as mild reaction... Poly(4-vinylpyridinium tribromide) is an efficient catalyst for the conversion of various alcohols to their corresponding acetate derivatives with acetic anhydride.This method has some advantages such as mild reaction conditions,good to excellent yields,and ease of work-up. 展开更多
关键词 ACYLATION poly(4-vinylpyridinium tribromide) acetic anhydride ALCOHOL ACETATE
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Synthesis, Crystal Structure, Docking and Antifungal Activity of a New Pyrazole Acylurea Compound 被引量:6
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作者 金涛 翟志文 +3 位作者 韩亮 翁建全 谭成侠 刘幸海 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第8期1259-1264,共6页
The title compound N-((3,5-dimethylphenyl)carbamoyl)-1-methyl-3-(trifluoromethyl)-1 H-pyrazole-4-carboxamide(C(15)H(15)F3N4O2) was synthesized, and its structure was confirmed by 1 H NMR, H RMS and X-ray d... The title compound N-((3,5-dimethylphenyl)carbamoyl)-1-methyl-3-(trifluoromethyl)-1 H-pyrazole-4-carboxamide(C(15)H(15)F3N4O2) was synthesized, and its structure was confirmed by 1 H NMR, H RMS and X-ray diffraction. It crystallizes in the triclinic system, space group P1 with a = 11.7147(5), b = 11.7935(5), c = 13.6620(5) A, α = 69.755(7)°, β = 66.182(6)°, γ = 72.100(7)°, Dc = 1.423 g/cm^3, Z = 4, V = 1588.88(11) A^3, the final R = 0.0347 and wR = 0.1005 for 7171 observed reflections with I 〉 2σ(I). The preliminary biological test showed that the title compound has antifungal activities against Fusarium oxysporum, Pseudomonas syringae, Corynespora mazei and Botrytis cinerea at 100 μg/mL as 5.19%, 53.50%, 88.55% and 70.62%, respectively. The docking results indicated the hydrogen bonds formed between the compound and SHD. 展开更多
关键词 pyrazole acyl urea SYNTHESIS crystal structure fungicidal activities DOCKING
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Regioselective enzymatic acylation of troxerutin in nonaqueous medium 被引量:3
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作者 Xiao, Yong Mei Mao, Pu +2 位作者 Zhao, Zhen Yang, Liang Ru Lin, Xian Fu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期59-62,共4页
A series of monosubstituted troxerutin esters have been synthesized by enzyme-catalyzed regioselective acylation of troxerutin in nonaqueous medium.Using divinyl dicarboxylates(CH_2=CH-OOC-(CH_2)_n-COO-CH=CH_2,n = 2,3... A series of monosubstituted troxerutin esters have been synthesized by enzyme-catalyzed regioselective acylation of troxerutin in nonaqueous medium.Using divinyl dicarboxylates(CH_2=CH-OOC-(CH_2)_n-COO-CH=CH_2,n = 2,3,4,7,8,11) featuring different chain length as acyl donors and alkaline protease from Bacillus subtilis as catalyst,troxerutin was regioselective acylated at B ethoxyl group.The results indicated that the regioselectivity of the enzyme-catalyzed acylation was not affected by the chain length o... 展开更多
关键词 TROXERUTIN ACYLATION Enzymatic synthesis Regioselectivity
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Analysis of Sucrose Esters with Long Acyl Chain by Coupling of HPLC-ELSD with ESI-MS System 被引量:5
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作者 朱金丽 汤艳峰 +1 位作者 李建华 张淑芬 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期1032-1037,共6页
The analysis of sucrose esters with long acyl chain by improved high performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD) and electrospray ionization mass spectrum (ESI... The analysis of sucrose esters with long acyl chain by improved high performance liquid chromatographic method with evaporative light scattering detection (HPLC-ELSD) and electrospray ionization mass spectrum (ESI-MS) is investigated. The improved HPLC-ELSD method for the separation and quantitation of commercial and synthesized sucrose esters is described. Samples are analyzed by means of a reversed-phase (RP) HPLC using a Hypersil C8 column (250 mm× 4.6 mm, 5 μm particle size) with methanol-tetrahydrofuran (vo)ume ratio of 90 : 10) and water under gradientcondition as the mobile phase, in which the flow rate is 1.0 ml·min^-1 and the column temperature is set at 40℃. This procedure provides a complete separation and determination ot monoester, diester, triester and higher esters with different acyl chain lengths in each fraction by a single run, in combination with the ESI-MS technology. With this method, it is possible to determine the approximate compositions of monoto polyesters in one analysis and quantitate pure positional isomers precisely using an external standard method. It is found that the method of ESI-MS coupling with HPLC system for the analysis of sucrose esters is straight forward, rapid and inexpensive, and can be readily applied in synthesis, purification and structure studies. 展开更多
关键词 sucrose esters long acyl chain ANALYSIS high performance liquid chromatographic method with evaporative light scattering detection electrospray ionization mass spectrum
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Two new C-glycosylflavones from the leaves of Iris lactea var. chinensis 被引量:3
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作者 Wen Juan Shen Min Jian Qin +1 位作者 Pan Shu Chao Feng Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第7期821-824,共4页
Two new acylated C-glycosylflavones were isolated from the leaves of Iris lactea var. chinensis, and their structures were elucidated on the basis of extensive NMR experiments and mass spectrometry methods and were as... Two new acylated C-glycosylflavones were isolated from the leaves of Iris lactea var. chinensis, and their structures were elucidated on the basis of extensive NMR experiments and mass spectrometry methods and were assigned as 5-hydroxy-4'- methoxyflavone-7-O-(β-D-2''''4''''-diacetylrhamnopyranosyl)-6-C-[ O-(α-L-6'''-acetyl-glucpyranosyl)-1→2-β-D-glucopyrano- side] (irislactin A) and 5-hydroxy-4',7-dimethoxyflavone-6-C-[O-(α-L-2''',3'''-diacetylrhanmo-pyranosyl)-1→ 2-β-D-glucopyranoside] (irislactin B). 展开更多
关键词 Iris lactea IRIDACEAE Acylated C-glycosylflavone
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A mild and facile method for one pot synthesis of 2,5-di-substituted 1,3,4-oxadiazoles at room temperature 被引量:3
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作者 Shahnaz Rostamizadeh Somaye Ghamkhar 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第6期639-642,共4页
2,5-Di-substituted 1,3,4-oxadiazoles 3a-n have been synthesized as a one pot procedure from the reaction of acid hydrazide 1, acyl halides 2 and phosphorus pentoxide in acetonitrile at room temperature. High yield, sh... 2,5-Di-substituted 1,3,4-oxadiazoles 3a-n have been synthesized as a one pot procedure from the reaction of acid hydrazide 1, acyl halides 2 and phosphorus pentoxide in acetonitrile at room temperature. High yield, short reaction time (10-15 min), mild condition, and easy work-up are advantages of this methodology. 展开更多
关键词 1 3 4-OXADIAZOLE Acid hydrazide Acyl halide Phosphorus pentoxide
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