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一锅法制备1-吡啶基-3-哌啶-4-甲酸的合成研究
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作者 陈艳君 杨伟群 董海仟 《化工设计通讯》 2024年第1期117-119,共3页
N杂环类分子是一类重要的医药切块分子,多用作多肽类医药分子的合成原料中间体。报道了一种N杂环类分子1-吡啶基-3-哌啶-4-甲酸新的合成方法。高压反应釜依次加入3-溴吡啶、4-哌啶甲酸乙酯、碳酸钾、N-甲基吡咯烷酮,反应釜密封好,升温至... N杂环类分子是一类重要的医药切块分子,多用作多肽类医药分子的合成原料中间体。报道了一种N杂环类分子1-吡啶基-3-哌啶-4-甲酸新的合成方法。高压反应釜依次加入3-溴吡啶、4-哌啶甲酸乙酯、碳酸钾、N-甲基吡咯烷酮,反应釜密封好,升温至180℃,压力保持0.5MPa,液质监测反应,反应72h,原料反应完毕。将反应体系冷却至室温后抽滤,滤饼用甲醇打浆后再次抽滤,将滤液浓缩后再甲醇重结晶得黄色粉末,产率最高可达46%。该合成方法,碱性高压条件,一锅法得到目标化合物,极大地降低了工业成本,且后处理方法简单且收率高,具有工业化生产前景。 展开更多
关键词 3-溴吡啶 4-哌啶甲酸乙酯 碳酸钾 N-甲基吡咯烷酮 甲醇
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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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稀土修饰对Cu/Al_(2)O_(3)催化乙酰丙酸乙酯加氢性能的影响
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作者 商宗玲 张弨 赵凤玉 《应用化学》 CAS CSCD 北大核心 2024年第3期340-348,共9页
生物质催化转化制大宗化学品符合低碳战略的重要研究方向,将纤维素衍生物乙酰丙酸乙酯转化为1,4-戊二醇是最具前景的技术路线之一。非贵金属铜基催化剂在该反应中表现出较好的活性,Cu/Al_(2)O_(3)在160℃、4 MPa H_(2)条件下催化乙酰丙... 生物质催化转化制大宗化学品符合低碳战略的重要研究方向,将纤维素衍生物乙酰丙酸乙酯转化为1,4-戊二醇是最具前景的技术路线之一。非贵金属铜基催化剂在该反应中表现出较好的活性,Cu/Al_(2)O_(3)在160℃、4 MPa H_(2)条件下催化乙酰丙酸乙酯氢解制1,4-戊二醇收率为50.8%,经稀土改性后催化剂的活性和选择性显著提升,其中CuNd0.25/Al_(2)O_(3)催化剂上获得1,4-戊二醇的收率高达92.7%。通过对催化剂性能以及X射线衍射(XRD)、透射电子显微镜(TEM)、氢气程序升温还原(H_(2)-TPR)、氢气程序升温脱附(NH3-TPD)和CO红外吸附(CO-DRIFT)等表征结果的分析发现,稀土元素的存在不仅改变了Cu活性中心的还原性质、分散度和电子结构,还改变了催化剂表面酸、碱性位点的分布。稀土元素的修饰既促进了催化剂表面反应物的吸附与活化,又抑制了目标产物1,4-戊二醇的脱水副反应,从而提高了活性和选择性。 展开更多
关键词 Cu/Al_(2)O_(3)催化剂 稀土修饰 1 4-戊二醇 乙酰丙酸乙酯 氢解
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Synthesis and Antitumor Activity of 3-[2-(4-Hydroxy-Phenyl)-Ethyl]-Benzo[d] Isoxazole-4,6-Diol
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作者 Li Wang 《International Journal of Organic Chemistry》 CAS 2023年第1期1-6,共6页
A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characteriz... A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characterized by 1H NMR, 13C NMR and HR-MS. The phloretin, compound 1, resveratrol and acetylated resveratrol were determined by comparing them with paclitaxel. Anti-tumor activity of alcohol on SPC-A1, EC109, A549, MCF-7 and MDA-MB-231 cell lines. Compound 1 showed better antitumor activity than docetaxel against A549 tumor cells. 展开更多
关键词 3-[2-(4-Hydroxy-Phenyl)-ethyl]-Benzo[d] Isoxazole-4 6-Diol SYNTHESIS Antitumor Activity
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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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Preparation of Ni(HCO_3)_2 and its catalytic performance in synthesis of benzoin ethyl ether 被引量:1
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作者 吴旭 安霞 谢鲜梅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1440-1445,共6页
Ni(HCO3)2 with unique phase and high crystallinity was synthesized with urea hydrolysis. The as-prepared samples were well characterized in detail. N2 adsorption and desorption result manifests a high surface area o... Ni(HCO3)2 with unique phase and high crystallinity was synthesized with urea hydrolysis. The as-prepared samples were well characterized in detail. N2 adsorption and desorption result manifests a high surface area of 99.03 m2/g with a pore size of 7.8 nm. Scanning electron microscopy (SEM) and particle size distribution reveal that the diameters of the formed pellets are uniform. Thermogravimetry (TG) analysis result shows that 500 ℃ could be the appropriate temperature for converting Ni(HCO3)2 precursors into NiO via a thermal decomposition process. CO2 and NH3 temperature-programmed desorption results show that Ni(HCO3)2 has explicit acid-base sites. Transmission electron microscopy (TEM) results vividly indicate that the pellets are aggregated by hexagonal platelets and possess porous structures. Ni(HCO3)2 can efficiently catalyze the one-step synthesis of benzoin ethyl ether from benzaldehyde and ethanol, with the conversion ofbenzaldehyde up to 57.5% and nearly 100% selectivity of benzoin ethyl ether. 展开更多
关键词 Ni(HCO3)2 CATALYSIS green synthesis benzoin ethyl ether
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Synthesis and in vitro-Anti-hepatitis B Virus Activities of Several Ethyl 5-Hydroxy-1H-indole-3-carboxylates 被引量:16
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作者 ZHAO Chun-shen ZHAO Yan-fang CHAI Hui-fang GONG Ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第5期577-583,共7页
A series of ethyl 5-hydroxyindole-3-earboxylates 6a-10r was designed and synthesized. The structures of all the compounds were confirmed by IR, ^1H NMR, and MS and their anti-hepatitis B virus (HBV) activities were ... A series of ethyl 5-hydroxyindole-3-earboxylates 6a-10r was designed and synthesized. The structures of all the compounds were confirmed by IR, ^1H NMR, and MS and their anti-hepatitis B virus (HBV) activities were evaluated in 2.2.15 cells. Among them, compound 7g { ethyl 5-hydroxy-2- [ ( 3-methoxyphenylsulfinyl ) methyl ] -1-methyl-4- [ (4-methylpiperazin-1-yl) methyl ]-1H-indole-3-carboxylate} displays a significant anti-HBV activity, which is more potent than the positive control lamivudine. 展开更多
关键词 ethyl 5-hydroxy-1H-indole-3-carboxylates SYNTHESIS Anti-hepatitis B virus activity
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Synthesis and biological evaluation of ethyl 6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylates against Eimeria tenella 被引量:5
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作者 Zhang, Yuan Yuan Zeng, Xing Yan +3 位作者 Nie, Kui Zhong, Zhi Cheng Wang, Yu Liang Wang, Yu Zhong 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第4期426-428,共3页
A series of ethyl 6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylates were designed and synthesized.Their structures were confirmed by ~1H NMR,^(13)C NMR,IR and HRMS.The biological activities were primarily evaluated ... A series of ethyl 6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylates were designed and synthesized.Their structures were confirmed by ~1H NMR,^(13)C NMR,IR and HRMS.The biological activities were primarily evaluated against Eimeria tenella according to Anticoccidial Index(ACI) method in vivo.The results showed that compounds 5e,5f and 5i exhibited anticoccidial activities against E.tenella at 27 mg kg^(-1). 展开更多
关键词 ethyl 6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylate Synthesis Anticoccidial activity Eimeria tenella
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Synthesis, Bioactivity, and Crystal Structure Analysis of 2-(3-Oxobenzo[d]isothiazol-2(3H)-yl)ethyl Benzoates 被引量:3
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作者 王向辉 游诚航 林强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第8期1123-1130,共8页
Fifteen novel 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl benzoates were synthesi- zed by the condensation of 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one with substituted benzoic acids in dichloromethane. All... Fifteen novel 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl benzoates were synthesi- zed by the condensation of 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one with substituted benzoic acids in dichloromethane. All the compounds were characterized by elemental analysis, IR, ESI-MS and 1H NMR. The crystal structures for 2-(2-hydroxyethyl)benzo[d]isothiazol-3(2H)-one (2) and 2-(3-oxobenzo[d]isothiazol-2(3H)-yl)ethyl 2-methoxybenzoate (30) have been determined by X-ray crystal structure analysis. Compound 2 (C9H9NO2S) crystallizes in the monoclinic system, space group Pn with a = 10.552(3), b = 7.849(2), c = 10.765(4) A, β = 103.128(4)°, V= 868.3(5) A3, Mr = 195.24, Dc = 1.493 Mg.m-3, μ = 0.33 mm-1, F(000) = 408, Z = 4, R= 0.0314 and wR= 0.0628. Compound 30 (C17H15NO4S) crystallizes in the triclinic system, space group P1 with a = 8.028(2), b = 9.300(2), c = 10.430(3)A, V= 752.1(3)A3, Mr = 329.36, D,= 1.454 Mg.m-3, p = 0.24 mm-1, F(000) = 344, Z = 2, R = 0.0377 and wR = 0.0904. The preliminary biological test indicated that the title compounds show better growth inhibitory activity against the gram-positive bacteria than the gram-negative bacteria. 展开更多
关键词 2-(3-oxobenzo[d]isothiazoi-2(3H)-yl)ethyl benzoates synthesis crystal structure hydrogen bonds
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Efficient Synthesis of 2-Ethyl-A-ring Analogues of 19-Nor-1α,25-dihydroxy Vitamin D_3 被引量:1
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作者 WangQiu-an ZHAOYu-rui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期165-173,共9页
The novel 19 nor l α ,25 dihydroxy vitamin D 3 analogues possessing an ethyl at the 2 position(4 and 5), were synthesized by coupling 25 hydroxy Windaus Grundmann ketone derivative 20 with A ring syntho... The novel 19 nor l α ,25 dihydroxy vitamin D 3 analogues possessing an ethyl at the 2 position(4 and 5), were synthesized by coupling 25 hydroxy Windaus Grundmann ketone derivative 20 with A ring synthons(15 and 19) respectively. The enantioselective synthesis of substituted bicyclic hexanes structure A ring synthons, started from all cis 3,5 dihydroxy 4 ethyl 1 (methoxycarbonyl)cyclohexane via lipase catalyzd asymmetrization, was demonstrated. 展开更多
关键词 ethyl 19 nor 1 α 25 dihydroxy vitamin D 3 Synthesis Lipase catalyzed Asymmetrization
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Synthesis and Crystal Structure of a Novel Ethyl 5-(4-(2-Phenylacetamido)phenyl)-1H-pyrazole-3-carboxylate as an Acrosin Inhibitor 被引量:2
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作者 祁晶晶 周有骏 +5 位作者 刘雪飞 丁莉莉 郑灿辉 盛春泉 吕加国 朱驹 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1604-1608,共5页
The title compound (ethyl5-(4-(2-phenylacetamido)phenyl)-lH-pyrazole-3-carboxylate, C20H19N3O3) was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was ch... The title compound (ethyl5-(4-(2-phenylacetamido)phenyl)-lH-pyrazole-3-carboxylate, C20H19N3O3) was synthesized by the reaction of Claisen condensation, cyclization, reduction and acylation. The structure was characterized by X-ray diffraction, MS, NMR and IR. It belongs to the monoclinic system, space group C2/c with a = 22.723(9), b = 9.324(4), c = 18.890(8) A, β = 114.259(6)°, V = 3649(3) A^3, Dc = 1.272 Mg·m^3, Z = 8, Mr = 349.38, p = 0.087 mm^-1, F(000) = 1472, the final R = 0.0615 and wR = 0.1643. The biological test shows that the title compound has a moderate acrosin inhibition activity. 展开更多
关键词 ethyl 5-(4-(2-phenylacetamido)phenyl)-1H-pyrazole-3-carboxylate crystal structure acrosin inhibitor
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Synthesis, Crystal Structure and Antitumor Activities of N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline 被引量:1
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作者 贺殿 杨竹青 侯猛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第12期1784-1788,共5页
The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, I... The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, IR, H RMS(ESI) and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group I2/c with a = 15.0212(10), b = 9.4911(6), c = 20.3075(13) A, β = 100.776(7)o, V = 2844.1(3)A3, Z = 8, Dc = 1.314 g/cm3, F(000) = 1184.0, μ = 0.089 mm-1, the final R = 0.0574 and w R = 0.1688 for 1701 observed reflections(I 】 2σ(I)). X-ray analysis indicates three major N(2)–H(2)···O(2), C(13)–H(13)···O(2), N(2)–H(2)···N(3) hydrogen bonds and π-π stacking interactions in the crystal structure. The preliminary biological test shows that the title compound has a good antitumor activity against A549 in vitro with the IC50 value of 35 μmol/L. 展开更多
关键词 crystal structure SYNTHESIS N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline biological activity
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Synthesis and Crystal Structure of Ethyl 3-(4-Chlorophenyl)-3,4-dihydro-6-methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate 被引量:2
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作者 胡扬根 徐靖 丁明武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第6期689-692,共4页
The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined... The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit. 展开更多
关键词 crystal structure ethyl 3-(4-ehlorophenyl)-3 4-dihydro-6-methyl-4-oxo-2- (pyrrolidin-1-yl)furo[2 3-d]pyrimidine-5-earboxylate aza-Wittig reaction synthesis
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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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Long-term and combined effects of N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide and fumaric acid on methane production,rumen fermentation, and lactation performance in dairy goats 被引量:1
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作者 Zongjun Li Xinjian Lei +3 位作者 Xiaoxu Chen Qingyan Yin Jing Shen Junhu Yao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第3期852-863,共12页
Background:In recent years,nitrooxy compounds have been identified as promising inhibitors of methanogenesis in ruminants.However,when animals receive a nitrooxy compound,a high portion of the spared hydrogen is eruct... Background:In recent years,nitrooxy compounds have been identified as promising inhibitors of methanogenesis in ruminants.However,when animals receive a nitrooxy compound,a high portion of the spared hydrogen is eructated as gas,which partly offsets the energy savings of CH4mitigation.The objective of the present study was to evaluate the long-term and combined effects of supplementation with N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide(NPD),a methanogenesis inhibitor,and fumaric acid(FUM),a hydrogen sink,on enteric CH4production,rumen fermentation,bacterial populations,apparent nutrient digestibility,and lactation performance of dairy goats.Results:Twenty-four primiparous dairy goats were used in a randomized complete block design with a 2×2factorial arrangement of treatments:supplementation without or with FUM(32 g/d)or NPD(0.5 g/d).All samples were collected every 3 weeks during a 12-week feeding experiment.Both FUM and NPD supplementation persistently inhibited CH4yield(L/kg DMI,by 18.8%and 18.1%,respectively)without negative influence on DMI or apparent nutrient digestibility.When supplemented in combination,no additive CH4suppression was observed.FUM showed greater responses in increasing the molar proportion of propionate when supplemented with NPD than supplemented alone(by 10.2%vs.4.4%).The rumen microbiota structure in the animals receiving FUM was different from that of the other animals,particularly changed the structure of phylum Firmicutes.Daily milk production and serum total antioxidant capacity were improved by NPD,but the contents of milk fat and protein were decreased,probably due to the bioactivity of absorbed NPD on body metabolism.Conclusions:Supplementing NPD and FUM in combination is a promising way to persistently inhibit CH4emissions with a higher rumen propionate proportion.However,the side effects of this nitrooxy compound on animals and its residues in animal products need further evaluation before it can be used as an animal feed additive. 展开更多
关键词 Bacterial populations Dairy goat Fumaric acid Lactation performance Methane emissions N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide Rumen fermentation
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DFT Study on the Structure of Ionic Liquid 1-Ethyl-3-methylimidazolium Hexafluorophosphate 被引量:1
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作者 刘坤辉 蒲敏 陈标华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第5期576-580,492,共6页
This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) metho... This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) methods are respectively used to obtain the stable structure of the gas phase ion pair at the 6-311++G(d, p) basis set level. The theoretical IR spectra of [EMIM]+[PF6]- were obtained from the calculated vibrational frequencies and intensities. The changes of atomic charge population have been investigated using Natural Bond Orbital (NBO) analysis. The computational results show that there may exist hydrogen bonds between the cation and the anion. After ZPE and BSSE corrections, the interaction energy between the cation and the anion is –314.44 kJ?mol-1. 展开更多
关键词 ionic liquids 1-ethyl-3-methylimidazolium hexafluorophosphate DFT
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N-乙基咔唑-3-甲醛席夫碱荧光探针的合成及其检测Cu^(2+)性质 被引量:1
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作者 董智云 郭昌晟 +3 位作者 高琳 顼兴宇 刘成琪 席福贵 《无机化学学报》 SCIE CAS CSCD 北大核心 2023年第5期859-866,共8页
以咔唑为原料,经过两步反应制备得到N-乙基咔唑-3-甲醛,其结构经X射线单晶衍射测定属于单斜晶系,空间群为P2_(1)/n。再以N-乙基咔唑-3-甲醛与1,3-二氨-2-丙醇为原料,设计、合成了一种新型双席夫碱荧光探针分子CMP。借助荧光光谱在体积比... 以咔唑为原料,经过两步反应制备得到N-乙基咔唑-3-甲醛,其结构经X射线单晶衍射测定属于单斜晶系,空间群为P2_(1)/n。再以N-乙基咔唑-3-甲醛与1,3-二氨-2-丙醇为原料,设计、合成了一种新型双席夫碱荧光探针分子CMP。借助荧光光谱在体积比为6∶4的DMSO/H_(2)O缓冲溶液(Tris-HCl,pH=7.0)中研究了探针CMP对Cu^(2+)的选择性识别。研究结果表明,探针CMP与Cu^(2+)以1∶2的比例配位,结合常数为1.52×10^(5) L·mol^(-1),检出限为0.205μmol·L^(-1)。回收实验表明,探针分子CMP可应用于环境水样中Cu^(2+)的检测。 展开更多
关键词 N-乙基咔唑-3-甲醛 席夫碱 荧光探针 Cu^(2+) 荧光猝灭
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Ab Initio Calculation of Room Temperature Ionic Liquid 1-Ethyl-3-Methyl-Imidazolium Chlorocuprate (Ⅰ) 被引量:1
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作者 Renqing Lue Hejin Tangbo Zuogang Cao 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第1期70-77,共8页
The Hartree-Fock method has been employed to investigate the electronic structures of EMIM^+(1-ethyl-3-methyl-imidazolium^+), CuCl2^-, Cu2Cl3^-, CuCl3^2-, EMIM+^-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- pa... The Hartree-Fock method has been employed to investigate the electronic structures of EMIM^+(1-ethyl-3-methyl-imidazolium^+), CuCl2^-, Cu2Cl3^-, CuCl3^2-, EMIM+^-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- pairs. Full optimization and frequency analyses of EMIM^+, CuCl2^-, Cu2Cl3^-, CuC13^-, eight initial EMIM^+-CuCl2^-, six EMIM^+-Cu2Cl3^-, and four EMIM^+-CuCl3^2- geometries have been carried out using Gaussian-94 soft-package at 6-31+G(d,p) basis set level for hydrogen, carbon, nitrogen, chlorine atoms and Hay-Wadt effective core potential for copper atom. The electronic structures of lowest energy of EMIM^+-CuCl2^-, EMIM+-Cu2Cl3^-, EMIM^+-CuCl3^2-, single EMIM^+, CuCl2^-, Cu2Cl3^-, and CuCl3^2- have been comparatively studied. The calculated results showed that EMIM^+-CuCl2^- pair conformer of lowest energy was five ring parallel to Cl-Cu-Cl with 3.2A distance, EMIM^+-CuCl3^2- pair conformer of lowest energy was five ring parallel to CuCl3^2-plane with 3.4A distance, and the optimized EMIM^+-Cu2Cl3^- pair conformer of lowest energy was five ring perpendicular to Cl-Cu-Cl-Cu-Cl plane with 3.0A distance between the terminal Cl atoms and the 5-ring of EMIM^+. The cohesion between cations and anions is brought about by C-H. C1 hydrogen bonds that are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum because of no appearing of imaginary frequency. The assigned frequencies were in agreement with the experimental report. The low energy of interaction because of the bulkyasymmetry of EMIM+ and the charge dispersion of cation and anion leads to the low melting point of the ionic liquids, EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2-. The interaction energy of EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^-, and EMIM^+-CuCl3^2- is 309.0 kJ/mol, 316.8 kJ/mol, and 320.2 kJ/mol, respectively. The relationship of interaction energy via distance between cations and anions was also investigated by single point energy scan. 展开更多
关键词 ionic liquid HARTREE-FOCK 1-ethyl-3-methyl-imidazolium chlorocuprate (I)
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Synthesis and Crystal Structure of Tri(4-(3-hydroxy2-ethyl-4-pyridinone-1-yl)-aniline Condensation Salicylaldehydato) Monohydratotricopper(II)Dimethylformamide Monohydrate Solvate 被引量:2
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作者 LUZai-Sheng NIUDe-Zhong +1 位作者 TUShu-Jiang CHENJiu-Tong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第6期681-686,共6页
The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H1... The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H15N2O3)3(H2O)]DMFH2O. The coordi- nation sphere about each copper ion in the complex consists of two oxygen atoms from hydroxylpyridinone moiety of one ligand and one oxygen and one nitrogen atoms from salicyladehyde Schiff-base moiety of another ligand arranged in a slightly distorted square planar geometry. Among the three copper ions, one (Cu(2)) is coordinated by the other oxygen atom of water molecule on the fifth coordinate position to form a distorted square pyramid geometry. The crystal is of monoclinic, space group P21/c with a = 12.9202(5), b = 27.197(1), c = 17.0116(7) ? b = 100.588(1), V = 5875.9(4) 3, Z = 4, C63H57N7O12Cu3, Mr = 1294.78, Dc = 1.464 g/cm3, m = 1.146 mm-1, F(000) = 2668, R = 0.0784 and wR = 0.1546 for 6926 observed reflections with I > 2s(I). The differences of coordinate bond lengths are observed between anhydrous and hydrous units: in the former unit, the average bond lengths are 1.978 ?for CuN (azomethine), 1.883 ?for CuO (phenolic) in Schiff-base moiety, 1.959 ?for CuO (keto), and 1.919 ?for CuO (hydroxy) in hydroxypyridinone moiety; while those in the latter are longer with the following corresponding values: 1.985(5), 1.908(5), 1.993(5) and 1.919(4) ? respectively. The Cu(2)O (water) bond length is 2.375(6) ? 展开更多
关键词 copper(II) complex 4-(3-hydroxy-2-ethyl-4-pyridinone-1-yl)-aniline salicylaldehyde Schiff-base crystal structure
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Epoxide Hydrolase-catalyzed Resolution of Ethyl 3-Phenylglycidate
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作者 CongFaLI QiaoLIU +3 位作者 HongJieCUI DiDING AiGuoJI YinBoQU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1133-1134,共2页
Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value o... Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value of 94.6 % was obtained from the racemic mixture. 展开更多
关键词 Epoxide hydrolase ethyl 3-phenylglycidate RESOLUTION asymmetric hydrolysis.
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