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Isolation and Expression Analysis of Two Genes Encoding Cinnamate 4-Hydroxylase from Cotton(Gossypium hirsutum) 被引量:4
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作者 NI Zhi-yong LI Bo +2 位作者 Neumann M Peter Lü Meng FAN Ling 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2102-2112,共11页
Two genes (GhC4H1 and GhC4H2) that encode putative cotton cinnamate 4-hydroxylases that catalyze the second step in the phenylpropanoid pathway were isolated from developing cotton fibers. GhC4H1 and GhC4H2 each con... Two genes (GhC4H1 and GhC4H2) that encode putative cotton cinnamate 4-hydroxylases that catalyze the second step in the phenylpropanoid pathway were isolated from developing cotton fibers. GhC4H1 and GhC4H2 each contain open reading frames of 1 518 base pairs (bp) in length and both encode proteins consisting of 505 amino acid residues. They are 90.89% identical to each other at the amino acid sequence level and belong to class I of plant C4Hs. GhC4H1 and GhC4H2 genomic DNA are 2 247 and 2 161 bp long, respectively, and contain two introns located at conserved positions relative to the coding sequence. GhC4HI and GhC4H2 promoters were isolated and found to contain many cis-elements (boxes P, L and AC-1 element) previously identified in the promoters of other phenylpropanoid pathway genes. Histochemical staining showed GUS expression driven by the GhC4H1 and GhC4H2 promoters in ovules and fibers tissues. GhC4H1 and GhC4H2 were also widely expressed in other cotton tissues. GhC4H2 expression reached its highest level during the elongation stage of fiber development, whereas GhC4H1 expression increased during the secondary wall development period in cotton fibers. Our results contribute to a better understanding of the biochemical role of GhC4H1 and GhC4H2 in cotton fiber development. 展开更多
关键词 cinnamate 4-hydroxylase Gossypium hirsutum promoter analysis phenylpropanoid pathway
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New Process for the Synthesis of A Sun-screening Agent Isooctyl P-methoxy Cinnamate
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作者 Meng Juguang Li Fang +3 位作者 Li Jian Mo Linfeng Tan Yiping Xu Linshou 《China Detergent & Cosmetics》 2018年第3期49-51,共3页
A sun-screening agent isooctyl p-methoxy cinnamate was prepared by reaction of p-methoxyl benzaldehyde with isooctyl acetate using titanium tetrachloride as catalyst. The optimum conditions are as follows: molar rati... A sun-screening agent isooctyl p-methoxy cinnamate was prepared by reaction of p-methoxyl benzaldehyde with isooctyl acetate using titanium tetrachloride as catalyst. The optimum conditions are as follows: molar ratio of p-methoxyl benzaldehyde to isooctyl acetate and titanium tetrachloride is 1 : 1.1 : 0.5; reaction temperature is 30℃; and reaction time is 6 h. The yield of isooctyl p-methoxy cinnamate can reach 98%. The method of the synthesis of isooctyl p-methoxy cinnamate is efficient and economical. 展开更多
关键词 sun-screening agent isooctyl p-methoxy cinnamate SYNTHESIS
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HPLC Determination of Harpagoside and Cinnamic Acid in Radix Scrophulariae 被引量:5
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作者 谢丽华 刘洪宇 +4 位作者 徐秉玖 王璇 王建华 徐风 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期148-151,共4页
A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active... A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active constituent (harpagoside) for qualified Radix Scrophulariae. The experimental conditions were as follows: Ultrasphere ODS column (250 mm 4.6 mm, 5 mm), mobile phase: acetonitrile-water (containing 1.0% acetic acid) (20:8050:50) (20 min), flow-rate 1 mLmin-1, room temperature, detection wavelength 278 nm. Twenty-eight samples of Xuan-shen (Radix Scrophulariae) from different districts of China were analyzed and the contents of harpagoside and cinnamic acid in Xuan-shen were 0.041~0.244% and 0.012~0.068% respectively. The recoveries (RSD)% were 97.13(0.80)% for harpagoside and 99.38(0.51)% for cinnamic acid. The method is simple and accurate. It can be used for the quality control of Radix Scrophulariae. We propose that the content of harpagoside in qualified Radix Scrophularia should be no less than 0.05%. 展开更多
关键词 Scrophularia ningpoensis HARPAGOSIDE cinnamic acid HPLC
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Determination of Plasma Concentration of Cinnamic Acid by High-Performance Liquid Chromatography and Its Pharmacokinetics in Rats after Oral Administration of Zi-Shen Pill 被引量:5
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作者 戴荣华 宋宗华 +1 位作者 鞠涛 毕开顺 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第2期130-133,共4页
Aim To develop a simple and sensitive high-performance liquid chromatographicmethod for determination of plasma concentration of cinnamic acid and pharmacokinetic study in ratsafter a single oral dose of traditional C... Aim To develop a simple and sensitive high-performance liquid chromatographicmethod for determination of plasma concentration of cinnamic acid and pharmacokinetic study in ratsafter a single oral dose of traditional Chinese medicinal preparation Zi-Shen pill. Method Plasmasamples were acidified with hydrochloric acid and extracted with ethyl acetate . Cinnamic acid wasdetermined by HPLC using a G_(18) column. A mobile phase ofmethanbl-acetonitrile-water-triethyl-amine (7:22:73 = 0.2, V/V), with the pH adjusted to 4.0 withphosphoric acid, and with a UV detector set at 340 nm. Results The standard curve was linear overthe range of 1.92- 192.0 μg·mL^(-1). The LLOQ was 1.92 μg·mL^(-1) . The RSDs of within-day andbetween-day precision were < 8%. The mean recovery was 82.0% . Conclusion After validation, themethpd has been used to investigate the pharmacokinetic profiles of the traditional Chinesemedicinal preparation Zi-Shen pill. 展开更多
关键词 cinnamic acid Zi-shen pill PHARMACOKINETICS HPLC
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Anticancer Activities of Substituted Cinnamic Acid Phenethyl Esters on Human Cancer Cell Lines 被引量:4
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作者 李树春 李辉 +2 位作者 张法 李中军 崔景荣 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第4期184-187,共4页
Caffeic acid phenethyl ester (CAPE) and sixteen substituted cinnamic acid phenethyl esters were prepared via conventional procedures in order to test their in vitro anticancer activities by either MTT assay or SRB... Caffeic acid phenethyl ester (CAPE) and sixteen substituted cinnamic acid phenethyl esters were prepared via conventional procedures in order to test their in vitro anticancer activities by either MTT assay or SRB assay on six different human cancer cell lines. The results indicated that in the concentration of 10 μmol·L -1 the lead compound CAPE possessed anticancer activities against human HL 60, Bel 7402, and Hela cell lines, and two other compounds possessed potent anticancer activities against Bel 7402 and Hela cell lines. 展开更多
关键词 medicinal chemistry cinnamic acid phenethyl esters chemical synthesis anticancer activity
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茉莉酸甲酯复合肉桂酸钾处理对芒果采后抗病性及品质的影响
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作者 陈叶珍 胡美姣 +3 位作者 李敏 高兆银 潘永贵 弓德强 《保鲜与加工》 北大核心 2025年第2期54-61,共8页
为探讨茉莉酸甲酯(MeJA)复合肉桂酸钾(PC)处理对芒果果实采后抗病性和内在品质的影响,以‘贵妃’芒果果实为试材,采用10μmol/L的MeJA复合PC(25、50、100 mmol/L)溶液浸泡芒果10 min,以清水处理为对照(CK),各处理组随机选取部分果实接... 为探讨茉莉酸甲酯(MeJA)复合肉桂酸钾(PC)处理对芒果果实采后抗病性和内在品质的影响,以‘贵妃’芒果果实为试材,采用10μmol/L的MeJA复合PC(25、50、100 mmol/L)溶液浸泡芒果10 min,以清水处理为对照(CK),各处理组随机选取部分果实接种炭疽菌,处理后的果实在室温(25±1)℃下贮藏12 d,并定期(每3 d)测定接种炭疽菌果实的病斑直径和未接菌果实的病情指数、果皮防御相关酶活性及果肉可溶性固形物、VC、有机酸含量等指标。结果表明,与CK相比,MeJA复合PC处理显著降低了芒果果实的病斑直径和病情指数,其中10μmol/L MeJA复合50 mmol/L PC处理效果最好,在12 d时,病斑直径和病情指数分别降低了43.56%和52.94%,并且该复合处理显著提高了接菌芒果果皮中苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、过氧化物酶(POD)和β-1,3-葡聚糖酶(GLU)4种与抗病性相关防御酶的活性,其中在9 d时,与CK相比分别提高了19.22%、31.35%、57.28%和13.72%。另外,该复合处理也有效提高了芒果常温贮藏后期果肉中可溶性固形物含量,延缓了VC、柠檬酸、莽草酸和奎宁酸的降解,并提高了苹果酸含量,从而较好地保持果实的品质。因此,MeJA复合PC处理可有效提高芒果采后抗病性,并保持果实品质。研究结果可为芒果采后保鲜提供一定的理论依据和技术指导。 展开更多
关键词 芒果 茉莉酸甲酯 肉桂酸钾 抗病性 采后品质
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β-卡巴林-肉桂酸骨架化合物B4的合成、含量测定和稳定性研究
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作者 关丽 陈嘉欣 +4 位作者 宋鹏飞 赵惠茹 夏焱鑫 张胜杰 李伟泽 《中国新药杂志》 北大核心 2025年第7期771-777,共7页
目的:合成β-卡巴林-肉桂酸骨架化合物B4,对其进行含量测定、人工胃肠液稳定性研究及溶血性评价。方法:以5-甲氧基色胺为原料,通过Pictet-spengler反应合成卡巴林,并与4-氯肉桂酸缩合反应形成目标化合物;利用HPLC法对化合物B4进行定性... 目的:合成β-卡巴林-肉桂酸骨架化合物B4,对其进行含量测定、人工胃肠液稳定性研究及溶血性评价。方法:以5-甲氧基色胺为原料,通过Pictet-spengler反应合成卡巴林,并与4-氯肉桂酸缩合反应形成目标化合物;利用HPLC法对化合物B4进行定性定量分析,优化色谱条件,并进行方法学验证,利用该检测方法对其在模拟人工肠胃液中的稳定性进行考察;并对该化合物B4进行溶血性评价。结果:化合物B4通过^(1)H-NMR,^(13)C-NMR和ESI-MS确定其结构,最佳色谱条件为色谱柱YMC-Pack ODS-A色谱柱(250 mm×4.6 mm,5μm),甲醇∶水=90∶10,等度洗脱,流速1.0 mL·min^(-1),检测波长278 nm。该方法线性范围为1~100μg·mL^(-1),线性方程为y=126.96x+199.85(R^(2)=0.9994),平均回收率为104%。该化合物甲醇溶液在25℃下24 h内保持稳定;在酸性的人工胃液中不稳定,在0 min被迅速降解至消失,而在人工肠液中相对稳定,缓慢降解,直至150 min后降解完全。同时化合物B4在溶血性试验中显示无肉眼可见溶血及凝集现象,符合《中华人民共和国药典》相关规定。结论:建立了化合物B4的完整含量测定方法,其作为一种新合成的创新小分子在碱性溶液比在酸性溶液中稳定。 展开更多
关键词 β-卡巴林-肉桂酸骨架化合物 合成 含量测定 HPLC法 人工胃肠液 溶血试验
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富马酸和肉桂醛及其联合添加对断奶仔猪生长性能、血清生化和抗氧化指标以及肠道炎症反应的影响
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作者 刘禹彤 杨冠华 +3 位作者 王璐瑶 马欣怡 乔家运 李海花 《动物营养学报》 北大核心 2025年第3期1575-1584,共10页
本试验旨在探究富马酸和肉桂醛及其联合添加对断奶仔猪生长性能、血清生化和抗氧化指标以及肠道炎症反应的影响。选用初始体重为(7.79±0.48)kg的28日龄“杜×长×大”杂交断奶仔猪72头(公母各占1/2),随机分为4组,每组6个重... 本试验旨在探究富马酸和肉桂醛及其联合添加对断奶仔猪生长性能、血清生化和抗氧化指标以及肠道炎症反应的影响。选用初始体重为(7.79±0.48)kg的28日龄“杜×长×大”杂交断奶仔猪72头(公母各占1/2),随机分为4组,每组6个重复,每个重复3头猪,单栏饲养。对照组(CON组)饲喂基础饲粮,试验组分别饲喂在基础饲粮的基础上添加600 mg/kg富马酸(富马酸组,FA组)、400 mg/kg肉桂醛(肉桂醛组,CA组)和600 mg/kg富马酸+400 mg/kg肉桂醛(联合添加组,FC组)的饲粮。试验期28 d。试验结束当天08:00,每组抽取6头仔猪腹腔内注射200μg/kg BW脂多糖(LPS)。结果表明:1)与CON组相比,各试验组断奶仔猪末重、平均日增重(ADG)和平均日采食量(ADFI)均显著提高(P<0.05),料重比(F/G)均显著降低(P<0.05)。同时,FA组和FC组末重和ADG显著高于CA组(P<0.05)。2)与CON组相比,CA组和FC组断奶仔猪血清丙二醛(MDA)含量显著降低(P<0.05),血清过氧化氢酶(CAT)活性显著提高(P<0.05)。同时,FC组血清MDA含量显著低于FA组和CA组(P<0.05),血清CAT活性显著高于FA组和CA组(P<0.05)。3)与CON组相比,各试验组断奶仔猪血清肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)含量均显著降低(P<0.05)。同时,CA组和FC组血清TNF-α含量显著低于FA组(P<0.05)。4)与CON+LPS组相比,各试验组断奶仔猪空肠TNF-α和IL-6含量均显著降低(P<0.05),空肠白细胞介素-10(IL-10)含量均显著提高(P<0.05);FA+LPS组空肠转化生长因子-β(TGF-β)含量显著提高(P<0.05)。同时,FC+LPS组空肠TNF-α和IL-6含量显著低于FA+LPS组和CA+LPS组(P<0.05)。5)与CON+LPS组相比,各试验组断奶仔猪空肠Toll样受体4(TLR4)、核因子-κB(NF-κB)、TNF-α和IL-6 mRNA相对表达量均显著降低(P<0.05),空肠TGF-β和IL-10 mRNA相对表达量均显著提高(P<0.05)。综上所述,饲粮单独添加富马酸和肉桂醛或两者联合添加可以提高断奶仔猪生长性能、抗氧化功能和抗炎能力,且联合添加具有协同增效作用。 展开更多
关键词 富马酸 肉桂醛 断奶仔猪 生长性能 抗氧化 炎症反应
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一测多评法同时测定蒙药孟根·沃斯-18丸中10种化学成分
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作者 苏都那布其 荷叶 +3 位作者 莫日根 郝俊生 海金 王秀兰 《中国新药杂志》 北大核心 2025年第4期419-425,共7页
目的:建立HPLC一测多评法(quantitative analysis of multi-components by single marker,QAMS)同时测定蒙药孟根·沃斯-18丸中没食子酸、表儿茶素、鞣花酸、杨梅素、肉桂酸、丁香酚、橙黄决明素、甘松新酮、α-细辛脑和大黄酚等10... 目的:建立HPLC一测多评法(quantitative analysis of multi-components by single marker,QAMS)同时测定蒙药孟根·沃斯-18丸中没食子酸、表儿茶素、鞣花酸、杨梅素、肉桂酸、丁香酚、橙黄决明素、甘松新酮、α-细辛脑和大黄酚等10种成分,并验证该方法在蒙药孟根·沃斯-18丸质量分析中应用的可行性。方法:采用Agilent Eclipse Plus C_(18)色谱柱(250 mm×4.6 mm,5μm),流动相为乙腈(A)-0.2%磷酸溶液(B),梯度洗脱(0~60 min,5%A→25%A,波长210 nm;60~80 min,25%A→36%A,波长280 nm;80~145 min,36%A→75%A,波长250 nm),流速为1.0 mL·min^(-1);柱温为40℃。以鞣花酸为内参物,建立与其他9种待测成分的相对校正因子(f_(s/i)),采用f_(s/i)计算各成分的质量分数,同时用外标法(external standard method,ESM)测定,比较2种方法测定结果,评价QAMS在蒙药孟根·沃斯-18丸中应用的准确性。结果:蒙药孟根·沃斯-18丸中没食子酸、表儿茶素、杨梅素、肉桂酸、丁香酚、橙黄决明素、甘松新酮、α-细辛脑和大黄酚9种成分的fs/i重现性良好,分别为0.2422,0.2315,0.3199,0.2565,1.9699,1.2089,1.2602,0.5605和1.2132,QAMS,ESM所得结果接近。结论:该方法简便、稳定、重复性良好,可用于孟根·沃斯-18丸的质量控制。 展开更多
关键词 孟根·沃斯-18丸 相对校正因子 一测多评法 没食子酸 表儿茶素 鞣花酸 杨梅素 肉桂酸 丁香酚 橙黄决明素 甘松新酮 Α-细辛脑 大黄酚
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Effects of Cinnamic Acid on Bacterial Community Diversity in Rhizosphere Soil of Cucumber Seedlings Under Salt Stress 被引量:9
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作者 LIU Jing WU Feng-zhi YANG Yang 《Agricultural Sciences in China》 CAS CSCD 2010年第2期266-274,共9页
To investigate the effects of a plant autotoxin, cinnamic acid, on bacterial communities in the rhizosphere soil of cucumber seedlings under salt stress, we used cucumber as the experimental material, cinnamic acid as... To investigate the effects of a plant autotoxin, cinnamic acid, on bacterial communities in the rhizosphere soil of cucumber seedlings under salt stress, we used cucumber as the experimental material, cinnamic acid as the autotoxin, and NaCl to apply salt stress. Bacterial communities in the rhizosphere soil were analyzed using polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), and clone sequencing. Salt stress decreased the diversity of bacterial species in rhizosphere soil of cucumber seedlings at several growth stages. Cinnamic acid exacerbated the effects of salt stress at high concentrations, but alleviated its effects at low concentrations. Cloning and sequencing results indicated that DGGE bands amplified from soil samples showed high homology to uncultured bacterial species. Cinnamic acid at 50 mg kg^-1 soil improved cucumber growth and was the most effective treatment to alleviate the effects of salt stress on bacterial communities. 展开更多
关键词 BACTERIA cinnamic acid CUCUMBER salt stress PCR-DGGE
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Synthesis and Crystal Structure of (E)-4-(Benzyloxy)-2-(cinnamoyloxy)-N,N,N-trimethyl-4-oxobutan-1-aminium Chloride as a Double-prodrug 被引量:6
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作者 GONG Xiao-Wei LI Xun +3 位作者 LI Wei-Lu GAO Xu XU Wen-Fang ZHAI Hai-Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期177-182,共6页
A novel hydrochloride quaternary ammonium salt (E)-4-(benzyloxy)-2-(cinnamo- yloxy)-N,N,N-trimethyl-4-oxobutan-l-aminium chloride (Cz3HzgNO4Cl2, Mr = 454.37) has been synthesized via the sequence of acetylatio... A novel hydrochloride quaternary ammonium salt (E)-4-(benzyloxy)-2-(cinnamo- yloxy)-N,N,N-trimethyl-4-oxobutan-l-aminium chloride (Cz3HzgNO4Cl2, Mr = 454.37) has been synthesized via the sequence of acetylation and esterification by using L-carnitine (L-4-N-trimethy- lammonium-3-hydroxybutyric acid, LC) and cinnamic acid as the starting materials, and its crystal structure was determined by single-crystal X-ray diffraction method. The crystal belongs to monoclinic, space group P212121 with a = 10.1670(4), b = 10.4488(4), c = 22.9795(11)A, V = 2441.18(18)A3, Z = 4, Dc = 1.236 g/cm3,μ(MoKa) = 0.293 mm-1, F(000) = 960, Flack factor = -0.01(11), the final R = 0.0489 and wR = 0.1550 for 3350 observed reflections (I 〉 2σ(/)) and R = 0.0953 for all 5648 unique reflections. The crystal structure involves a conjugated system which shows a reverse olefin structure. 展开更多
关键词 L-caruitine cinnamic acid SYNTHESIS crystal structure
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RP-HPLC Determination and Pharmacokinetic Comparison of Cinnamic Acid in Rat Plasma After Administration of Di-Gu-Pi Decoction and Pure Cinnamic Acid 被引量:6
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作者 LI Kang BI Kai-shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第1期56-60,共5页
A sensitive, simple, and accurate method was developed for the determination and pharmacokinetic comparison of cinnamic acid in rat plasma after the administration of a Traditional Chinese Medicinal preparation, Di-Gu... A sensitive, simple, and accurate method was developed for the determination and pharmacokinetic comparison of cinnamic acid in rat plasma after the administration of a Traditional Chinese Medicinal preparation, Di-Gu-Pi decoction, and pure cinnamic acid using RP-HPLC. Di-Gu-Pi was extracted with 5% aqueous sodium bicarbonate, which was followed by purification with ion exchange column chromatography. The plasma samples taken from rats were deproteinized with methanol. The reversed-phase (HPLC) system with a Diamonsil C18 column and methanol-acetonitfile-water (8: 32: 60, volume ratio) (adjusted to pH = 3.0 with glacial acetic acid) as the mobile phase was employed for the separation of cinnamic acid in the plasma samples. The detection was set at 272 nm and 3-(p-fluoro-phenyl)-2-propenoic acid was chosen as the internal standard. The calibration curve was linear in a range from 0. 10 to 25.0μg/mL (R2 = 0. 9988, n = 9). The precision was 3.42%-10. 10%; the between-day precision was 2. 84%-8.91% ; the accuracy was - 1.51%-1.26% ; the mean recovery was 99. 9%. The method was found to be sensitive, simple, accurate and appropriate for the determination of cinnamic acid. 展开更多
关键词 Di-Gu-Pi decoction cinnamic Acid Pharmacokinetics RP-HPLC
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Efficient one-pot synthesis of n-butyl levulinate from carbohydrates catalyzed by Fe_2(SO_4)_3 被引量:8
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作者 Ran An Guizhuan Xu +2 位作者 Chun Chang Jing Bai Shuqi Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第3期556-563,共8页
Butyl levulinate(BL) is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the cat... Butyl levulinate(BL) is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the catalysis of metal sulfates was developed. The catalytic activity of a series of metal sulfates for the synthesis of BL from fructose was investigated. Among various metal sulfates, ferric sulfate Fe(SO)was found to be the most efficient catalyst, which gave a remarkably high BL yield of 62.8 mol% under the conditions of 463 K, 3 h, a catalyst dosage of 5.0 g/L, and fructose concentration of 25 g/L. Different carbohydrates including glucose, cellulose, inulin and sucrose were also used for one-pot synthesis of BL with the catalysis of Fe(SO), showing the yields of 39.6, 30.5, 56.6 and 50.1 mol%, respectively. In addition,the recycling and reuse of Fe(SO)was studied by characterizing them using powder X-ray diffraction(XRD), scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS). A plausible reaction pathway for the one-pot synthesis of BL from fructose was proposed. This study provides a facile and feasible way for the synthesis of BL from biomass. 展开更多
关键词 ONE-POT n-butyl levulinate Metal sulfate Carbohydrates
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Prevalence of gastric varices and results of sclerotherapy with N-butyl 2 cyanoacrylate for controlling acute gastric variceal bleeding 被引量:11
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作者 Khalid Mumtaz Shahid Majid +4 位作者 Hasnain A Shah Kashif Hameed Ashfaq Ahmed Saeed Hamid Wasim Jafri 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第8期1247-1251,共5页
AIM: To study the prevalence, predictors and control of bleeding following N-butyl 2 cyanoacrylate (NBC) sclerotherapy of gastric varix (GV). METHODS: We analyzed case records of 1436 patients with portal hypert... AIM: To study the prevalence, predictors and control of bleeding following N-butyl 2 cyanoacrylate (NBC) sclerotherapy of gastric varix (GV). METHODS: We analyzed case records of 1436 patients with portal hypertension, who underwent endoscopy during the past five years for variceal screening or upper gastrointestinal (GI) bleeding. Fifty patients with bleeding GV underwent sclerotherapy with a mean of 2 mL NBC for control of bleeding. Outcome parameters were primary hemostasis (bleeding control within the first 48 h), recurrent bleeding (after 48 h of esophagogastro-duodenoscopy) and in-hospital mortality were analyzed. RESULTS: The prevalence of GV in patients with portal hypertension was 15% (220/1436) and the incidence of bleeding was 22.7% (50/220). Out of the 50 bleeding GV patients, isolated gastric varices (IGV-Ⅰ) were seen in 22 (44%), gastro-oesophageal varices (GOV) on lesser curvature (GOV-Ⅰ) in 16 (32%), and GOV on greater curvature (GOV-Ⅱ) in 15 (30%). IGV-Ⅰ was seen in 44% (22/50) patients who had bleeding as compared to 23% (39/170) who did not have bleeding (P 〈 0.003). Primary hernostasis was achieved with NBC in all patients. Re-bleeding occurred in 7 (14%) patients after 48 h of initial sclerotherapy. Secondary hemostasis was achieved with repeat NBC sclerotherapy in 4/7 (57%). Three patients died after repeat sclerotherapy, one during transjugular intrahepatic portosystemic stem shunt (TIPSS), one during surgery and one due to uncontrolled bleeding. Treatment failure-related mortality rate was 6% (3/50). CONCLUSION: GV can be seen in 15% of patients with portal hypertension and the incidence of bleeding is 22.7%. NBC is highly effective in controlling GV bleeding. In hospital mortality of patients with bleeding GV is 6%. 展开更多
关键词 Gastric varices Portal hypertension n-butyl cyanoacrylate BLEEDING SCLEROTHERAPY
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Preparation,Characterization of Dawson-type Heteropoly Acid Cerium(Ⅲ) Salt and Its Catalytic Performance on the Synthesis of n-Butyl Acetate 被引量:9
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作者 曹小华 任杰 +3 位作者 徐常龙 张康华 占昌朝 蓝健 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第5期500-506,共7页
A novel cerium(Ⅲ) salt of Dawson type tungstophosphoric acid(Ce2P2W18O62·16H2O) was prepared by doping cerous nitrate in H6P2W18O62·13H2O powder and characterized by thermogravimetry and differential therma... A novel cerium(Ⅲ) salt of Dawson type tungstophosphoric acid(Ce2P2W18O62·16H2O) was prepared by doping cerous nitrate in H6P2W18O62·13H2O powder and characterized by thermogravimetry and differential thermal analyses(TG/DTA),Fourier transform infrared spectroscopy(FT-IR),X-ray powder diffraction(XRD),pyridine infrared spectroscopy(Py-IR) and scanning electron microscopy(SEM).Its catalytic activity was evaluated by the probe reaction of synthesis of n-butyl acetate with acetic acid and n-butanol.The effects of various parameters such as molar ratio of n-butanol to acetic acid,reaction temperature,reaction time,and catalyst amount have been studied by single factor experiment.The results show that Ce2P2W18O62·16H2O behaved as an excellent heterogeneous catalyst in the synthesis of n-butyl acetate.The optimum synthetic conditions were determined as follows︰molar ratio of n-butanol to acetic acid at 2.0︰1.0,mass of the catalyst being 1.44% of the total reaction mixture,reaction temperature of 120 ℃ and reaction time of 150 min.Under above conditions,the conversion of acetic acid was above 97.8%.The selectivity of n-butyl acetate based on acetic acid was,in all cases,nearly 100%.The catalysts could be recycled and still exhibited high catalytic activity with 90.4% conversion after five cycles of reaction.It was found by means of TG-DTA and Py-IR that the catalyst deactivation was due to the adsorption of a complex of by-product on the active sites on catalysts surface or the catalyst loss in its separation from the products.Compared with using sulfuric acid as catalyst,the present procedure with Ce2P2W18O62·16H2O is a green productive technology due to simple process,higher yield,catalyst recycling and no corrosion for the production facilities. 展开更多
关键词 cerous phosphotungstate Dawson structure CATALYST ESTERIFICATION n-butyl acetate
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Esterification of levulinic acid to n-butyl levulinate over heteropolyacid supported on acid-treated clay 被引量:11
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作者 S. Dharne V. V. Bokade 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第1期18-24,共7页
Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesi... Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesis of n-butyl levulinate by esterification of levulinic acid with n-butanol using heteropolyacid (HPA) supported on acid-treated clay montmorillonite (K10). 20% (w/w) dodecatungestophosphoric acid (DTPA) supported on K10 was found to be the most efficient catalyst with 97% levulinic acid conversion and 100% selectivity towards n-butyl levulinate. Effects of various process parameters were studied to examine the efficacy of 20% (w/w) DTPA/K10 for optimization of the activity. 展开更多
关键词 levulinic acid N-BUTANOL dodectungestophosphoric acid K10 n-butyl levulinate
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n-Butyl Pyridinium Nitrate as a Reusable Ionic Liquid Medium for Knoevenagel Condensation 被引量:10
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作者 Yi Qun LI Xin Ming XU Mei Yun ZHOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第5期448-450,共3页
The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in mo... The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in moderate yields. 展开更多
关键词 n-butyl pyridinium nitrate ionic liquid Knoevenagel condensation.
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Effects of Exogenous Cinnamic Acids on the Growth and Physiological Characteristics of Cucumber Seedlings 被引量:2
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作者 CHEN Li-xin WU Feng-zhi MA Feng-ming 《Agricultural Sciences in China》 CAS CSCD 2005年第10期747-751,共5页
In order to study the effects of exogenous cinnamic acids on plant growth, contents of photosynthetic pigment, root activities and ATPase activities of root membrane at cucumber seedling stage, the seedlings of Shando... In order to study the effects of exogenous cinnamic acids on plant growth, contents of photosynthetic pigment, root activities and ATPase activities of root membrane at cucumber seedling stage, the seedlings of Shandong Mici cucumber were tested. The results showed that seedlings growth, contents of photosynthetic pigment, root activities and ATPase activities of root membrane were inhibited by cinnamic acids. The growth and root activities of seedlings were significantly (P〈0.05) lower in the soil amended with 100 mg kg^-1 cinnamic acids compared to the control. The contents of chlorophyll a, chlorophyll a+b and carotenoid of seedlings significantly (P〈0.05) decreased in the soil amended with 200 mg kg^-1 cinnamic acids, whereas ATPase activities exhibited a higher sensitivity and greatly decreased in the soil amended with 50 mg kg^-1 cinnamic acids. These results suggested that cinnamic acids could induce a stress condition, and the stress intensities increased with enhanced cinnamic acid concentration. 展开更多
关键词 CUCUMBER cinnamic acids Photosynthetic pigment Root activities ATPASE
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Synthesis and Characterization of Rare Earth Tesnary Complexes with Cinnamic Acid and O-Phenanthroline 被引量:2
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作者 赵永亮 赵凤英 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期318-320,共3页
Thirteen solid rare earth tesnary complexes with cinnamic acid C 6H 5CH=CHCOOH, HL and o phenanthroline (phen), RE(phen)L 3 were synthesized. Their IR absorption spectra, molar conductance, TG DTA, X ray power d... Thirteen solid rare earth tesnary complexes with cinnamic acid C 6H 5CH=CHCOOH, HL and o phenanthroline (phen), RE(phen)L 3 were synthesized. Their IR absorption spectra, molar conductance, TG DTA, X ray power diffraction analysis and fluorescence spectra were studied. The results show that all coordination compounds are oxidized and decomposed around 400 ℃ to 540 ℃. They are all crystalline material. The fluorescence spectra indicate that the fluorescence emission intensity of Eu(phen)L 3 is the highest among them. 展开更多
关键词 rare earths cinnamic acid o phenanthroline IR spectra fluorescence spectra
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Reactive Distillation for Producing n-Butyl Acetate:Experiment and Simulation 被引量:5
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作者 田晖 黄智贤 +2 位作者 邱挺 王晓达 吴燕翔 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第5期980-987,共8页
In this paper, a reactive distillation (RD) column was applied for synthesis n-butyl acetate from n-butanol and acetic acid. The Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model and an equilibrium stage model f... In this paper, a reactive distillation (RD) column was applied for synthesis n-butyl acetate from n-butanol and acetic acid. The Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model and an equilibrium stage model for separation were employed to study the RD process. The results obtained from the equilibrium stage model agreed well with the experiments. The effects of operating variables on the n-butanol conversion and n-butyl acetate purity were further investigated. The optimal column configuration for the production of n-butyl acetate was designed with 5 rectifying stages, 8 reaction stages and 13 stripping stages by the simulation study. According to the simulation results, n-butanol conversion and n-butyl acetate purity all reached greater than 96%. 展开更多
关键词 reactive distillation ESTERIFICATION n-butyl acetate SIMULATION
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