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超高效液相色谱—串联质谱法测定动物源性食品中百菌清及其代谢物4-羟基百菌清残留量
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作者 刘小芳 李政 +2 位作者 何浩 蒋军杰 陈媛媛 《食品与机械》 CSCD 北大核心 2024年第9期66-72,共7页
[目的]建立超高效液相色谱—串联质谱法同时测定动物源性食品中百菌清及其代谢物4-羟基百菌清残留的检测方法。[方法]样品经1%乙酸—乙腈溶液振荡提取,正己烷脱脂,基质分散固相萃取剂(PSA、无水硫酸镁)净化,通过Waters BEH C18色谱柱分... [目的]建立超高效液相色谱—串联质谱法同时测定动物源性食品中百菌清及其代谢物4-羟基百菌清残留的检测方法。[方法]样品经1%乙酸—乙腈溶液振荡提取,正己烷脱脂,基质分散固相萃取剂(PSA、无水硫酸镁)净化,通过Waters BEH C18色谱柱分离,以乙腈—0.1%甲酸水溶液为流动相进行梯度洗脱,采用大气压化学电离源(APCI)负离子多反应监测模式(MRM)进行测定,基质匹配外标法定量。[结果]百菌清及4-羟基百菌清在5~500μg/L范围内线性关系良好,定量限均为0.005 mg/kg,平均回收率分别为69.3%~111.0%和65.3%~117.9%,相对标准偏差分别为1.6%~10.8%和1.1%~9.0%。[结论]该方法前处理简单快速,灵敏度高,准确可靠,可用于动物源性食品中百菌清及其代谢物4-羟基百菌清的同时测定。 展开更多
关键词 超高效液相色谱—串联质谱 百菌清 4-羟基百菌清 动物源性食品
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Synthesis and antibacterial activity of brominated 2′(4′)-nitro-3-hydroxy diphenyl ethers 被引量:1
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作者 Xue Tang Min Xie +3 位作者 Yong Xue Sun Jian Hua Li Zhi Cheng Zhong Yu Liang Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第4期435-438,共4页
Eight new brominated 2'(4')-nitro-3-hydroxy diphenyl ethers have been designed and synthesized. The structures of new compounds were confirmed by ^1H NMR, IR and HRMS. The bioactivity tests showed that these compo... Eight new brominated 2'(4')-nitro-3-hydroxy diphenyl ethers have been designed and synthesized. The structures of new compounds were confirmed by ^1H NMR, IR and HRMS. The bioactivity tests showed that these compounds possessed antibacterial activities against the tested bacteria. These new compounds cannot be transformed into dioxins when they were manufactured and used. 展开更多
关键词 Brominated 2'(4')-nitro-3-hydroxy diphenyl ether SYNTHESIS Antibacterial activity
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SO<sub>4</sub><sup>2-</sup>/SnO<sub>2</sub>-Catalyzed C3-alkylation of 4-hydroxycoumarin with secondary benzyl alcohols and <i>O</i>-alkylation with <i>O</i>-acetyl compounds 被引量:2
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作者 Venugopalarao Narayana Ravi Varala Pudukulathan Zubaidha 《International Journal of Organic Chemistry》 2012年第3期287-294,共8页
Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respecti... Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respectively, in acetic acid under reflux conditions with good yield of products. 展开更多
关键词 C-C and C-O bond formations Sulfated tin oxide (STO) reusability 4-hydroxy coumarin SECONDARY BENZYL alcohol SECONDARY BENZYL O-acetate
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Detection of NO_2 Based on 4-Carboxyl-4′-hydroxy Azobenzene and Its Cu(II) Complex
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作者 李建 龚云 +1 位作者 秦建波 林建华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第2期252-260,共9页
An organic ligand and its Cu(II) complex formulated as (C13HloN203)·5H2O (H2L·5H2O, 1) and Cu(HL)2(phen)·0.125H2O (2, H2L = 4-carboxyl-4′-hydroxy azobenzene, phen = 1,10-phenanthroline) hav... An organic ligand and its Cu(II) complex formulated as (C13HloN203)·5H2O (H2L·5H2O, 1) and Cu(HL)2(phen)·0.125H2O (2, H2L = 4-carboxyl-4′-hydroxy azobenzene, phen = 1,10-phenanthroline) have been synthesized and structurally characterized by single-crystal X-ray diffraction. In the two compounds, H2L and HL exhibit a trans-conformation. Complex 2 shows a mononuclear Cu(Ⅱ) structure with the hydroxyl group of HL uncoordinated. Complex 2 is assembled into a three-dimensional (3D) supramolecular architecture by hydrogen bonds and π-π stacking interactions. H2L and compound 2 can detect NO2 via reversible and irreversible color changes, respectively. The mechanism for the color changes is investigated. 展开更多
关键词 4-carboxyl-4-hydroxy azobenzene COMPLEX SYNTHESIS structure color change
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Synthesis and activities of new 4-hydroxybenzoxazolone derivatives
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作者 Tang, Li Ban, Shu Rong +2 位作者 Feng, Xiu E. Lin, Wen Han Li, Qing Shan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期63-66,共4页
A series of new 4-substituted benzoxazolone derivatives were synthesized according to a convenient method,their anti-inflammatory and analgesic activities in vivo were evaluated.All of them were new compounds,the stru... A series of new 4-substituted benzoxazolone derivatives were synthesized according to a convenient method,their anti-inflammatory and analgesic activities in vivo were evaluated.All of them were new compounds,the structures of all the synthesized compounds were confirmed by ~1H NMR,^(13)C NMR,ESI-MS and HR-MS.Most of the compounds exhibited anti-inflammatory activity. 展开更多
关键词 SYNTHESIS 4-hydroxy benzoxazolone derivatives Anti-inflammatory activity
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STUDIES ON THE SYNTHESIS OF DIMETHYI,4-HYDROXY -4'-METHOXY-5,6,5',6'-BISMETHYLENEDIOXYBIPHENYL-2,2'-DICAPBOXYLATE——AN ESSENTIAL METABOLITE OF DDB
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作者 Shu Li ZHAN Chun Zhen ZHANG Institute of Materia Medica,Chinese Academy of Medical Sciences Beijing 100050 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第1期29-32,共4页
This paper reports the total synthesis of dimethyl 4-hydroxy-4’-methoxy-5,6,5’,6’-bismethylenedioxybiphenyl-2,2’-dicarboxylate(Ⅱ). Various conditions for bromination were tried to find the best one for synthesis ... This paper reports the total synthesis of dimethyl 4-hydroxy-4’-methoxy-5,6,5’,6’-bismethylenedioxybiphenyl-2,2’-dicarboxylate(Ⅱ). Various conditions for bromination were tried to find the best one for synthesis of the key intermediate compd 6.After Lllmann condensation of 6 with 8 and hydrogenolysis, the title compd Ⅱ was obtained.It was proved to be identical with the isolated metabolite of DDB by spectral data. 展开更多
关键词 AN ESSENTIAL METABOLITE OF DDB BISMETHYLENEDIOXYBIPHENYL-2 2 DICAPBOXYLATE METHOXY-5 6 5 STUDIES ON THE SYNTHESIS OF DIMETHYI 4-hydroxy
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Facile Resolution of Racemic 4-Phenyl-2-hydroxy Butyrate via Enzymatic Esterification and Transesterification
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作者 Jin wang Xu Zu yi Li 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第12期927-928,共2页
The optically active R-4-phenyl-2-hydroxy butyrates were prepared by esterification of the racemic acid or transesterification of the racemic ester catalyzed by lipase from Candida cyclindra (CCL) in organic media.
关键词 Res Facile Resolution of Racemic 4-Phenyl-2-hydroxy Butyrate via Enzymatic Esterification and Transesterification
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Synthesis and Evaluation of 4-Hydroxy Quinolinone Derivatives as Antioxidants of Lubricating Grease
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作者 Modather F. Hussein Mostafa A. Ismail Refaat A. El-Adly 《International Journal of Organic Chemistry》 CAS 2016年第4期207-219,共13页
3-(5-(2.4-dichlorophyenyl)-4.5-dihydro-1H-pyrazol-3-yl)-4hydroxy-1-methylquinolin(1H)-one, 5-((4-hydroxy-8-methyl-2-oxo-1.2-dihydroquinolin-3-yl)methylene)-1-phenyl-2-hioxodihydropyrimidine-4.6(1H.5H)-dione, and 1-but... 3-(5-(2.4-dichlorophyenyl)-4.5-dihydro-1H-pyrazol-3-yl)-4hydroxy-1-methylquinolin(1H)-one, 5-((4-hydroxy-8-methyl-2-oxo-1.2-dihydroquinolin-3-yl)methylene)-1-phenyl-2-hioxodihydropyrimidine-4.6(1H.5H)-dione, and 1-butyl-4-hydroxy-3-(5-styryl-4.5-dihydro-1H-pyrazol-3yl)quinolin-2(1H)-one were synthesized and characterized by spectroscopy analysis. These compounds are designated I, II and III, respectively. The antioxidants efficiency of the synthesized compounds in lubricating greases had been investigated using ASTM d-942 and ASTM d-664. The obtained data showed that the total acid number and oxygen pressure drop of these compounds in lubricating greases decrease in the order: Comp.III. < Comp.I. < Comp.II. The antioxidant efficiency of the prepared quinolinones derivatives was discussed. Acceptable correlations were obtained between the obtained oxidation inhibition and the calculated quantum chemical parameters. 展开更多
关键词 Lubricating Greases ANTIOXIDANTS 4-hydroxy Quinolinone Quantum Chemical Calculation
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百菌清及其代谢物4-羟基百菌清在三七上的残留行为及膳食风险评估 被引量:12
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作者 李文希 浦恩堂 +2 位作者 代雪芳 黄丽 张雪燕 《农药学学报》 CAS CSCD 北大核心 2020年第3期510-520,共11页
为保证百菌清的安全使用,明确百菌清及其代谢物4-羟基百菌清在三七上的残留行为,2017年在云南三七主产区丘北、广南、弥勒和石林4地进行了百菌清在三七上的规范残留试验,建立了气相色谱(GC-ECD)测定三七中百菌清和超高效液相色谱-串联质... 为保证百菌清的安全使用,明确百菌清及其代谢物4-羟基百菌清在三七上的残留行为,2017年在云南三七主产区丘北、广南、弥勒和石林4地进行了百菌清在三七上的规范残留试验,建立了气相色谱(GC-ECD)测定三七中百菌清和超高效液相色谱-串联质谱(UPLCMS/MS)测定4-羟基百菌清残留的分析方法。样品中百菌清用V(乙酸乙酯):V(正己烷)=2:8混合溶液提取,硅胶固相萃取柱净化,GC-ECD检测;4-羟基百菌清用乙腈提取,N-丙基乙二胺(PSA)分散固相萃取净化,UPLC-MS/MS检测,外标法定量。结果表明:百菌清在三七块根和须根中的添加回收率为93%~98%,相对标准偏差(RSD)为3%~6%,定量限(LOQ)为0.05 mg/kg;4-羟基百菌清在三七块根和须根中的添加回收率为75%~94%,RSD为3%~9%,LOQ为0.02 mg/kg。丘北和广南的消解动态试验结果显示:百菌清在三七植株上的半衰期为8.4~8.5 d,4-羟基百菌清为16.5~17.3 d;百菌清和4-羟基百菌清在三七地下部分根系中的消解不符合一级动力学反应模型,在施药后45 d内,百菌清呈波动性缓慢下降,4-羟基百菌清呈波动性缓慢上升的趋势。4地的最终残留试验结果表明:采用40%百菌清悬浮剂,分别按其有效成分2400和3600 g/hm2的剂量喷雾施药3~4次,每次施药间隔为7 d,于末次施药后21 d采样测定,三七块根中百菌清的残留量为<0.05~3.14 mg/kg,4-羟基百菌清为0.19~1.54 mg/kg;三七须根中百菌清的残留量为0.085~0.760 mg/kg,4-羟基百菌清为0.46~4.48 mg/kg。膳食摄入风险评估结果显示,百菌清的国家估算每日摄入量(NEDI)为0.967 mg,风险概率(RQ%)为76.8%,4-羟基百菌清的NEDI为0.012 mg,RQ%为2.4%,对一般人群健康不会产生不可接受的风险。 展开更多
关键词 百菌清 4-羟基百菌清 三七 残留 膳食风险评估
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以甘油为碳源发酵高产反式-4-羟脯氨酸菌株的选育及营养优化
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作者 王金霞 黄建华 +3 位作者 于林 张震宇 岳春 孙付保 《食品与发酵工业》 CAS CSCD 北大核心 2016年第7期40-47,共8页
以低品级甘油为碳源进行微生物发酵合成反式-4-羟脯氨酸(Trans-4-hydroxy proline,Hyp)的探索。从实验室构建的重组菌E.coli BL21(DE3)/p UC19-ptrp2-Hyp出发,通过易错PCR随机突变和常压室温等离子体复合诱变处理,利用单菌落琼脂块和氨... 以低品级甘油为碳源进行微生物发酵合成反式-4-羟脯氨酸(Trans-4-hydroxy proline,Hyp)的探索。从实验室构建的重组菌E.coli BL21(DE3)/p UC19-ptrp2-Hyp出发,通过易错PCR随机突变和常压室温等离子体复合诱变处理,利用单菌落琼脂块和氨基酸显色相结合高通量筛选出1株以甘油为唯一碳源的Hyp高产菌P71。与葡萄糖培养基相比,该菌株更适合在甘油上生长并转化L-脯氨酸合成Hyp,发酵20 h产Hyp高达1.20g/L,比生长在葡萄糖培养基上高70%以上;比其出发菌株在葡萄糖培养基上产量提高了1倍以上。通过培养基成分系统优化,发现胰蛋白胨、Fe SO4和L-脯氨酸是3大主要影响因素,最适加量分别为7.01 g/L、11.51 g/L和1.41 mmol/L;在该条件下突变菌株摇瓶发酵12 h产Hyp达1.61 g/L,比优化前提高了50%。 展开更多
关键词 低品级甘油 重组大肠杆菌 反式-4-羟脯氨酸(Traas-4-hydroxy—L-proline Hyp) 复合突变 营养优化
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百菌清及其代谢产物(4-羟基百菌清)在油麦菜及土壤中的残留降解研究 被引量:9
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作者 姚芳 陈小微 +2 位作者 梁赤周 张寒 虞淼 《食品安全质量检测学报》 CAS 2018年第1期155-160,共6页
目的建立气相色谱法(gas chromatography,GC)和液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)测定油麦菜及土壤中百菌清及4-羟基百菌清残留的方法,同时研究油麦菜及土壤中百菌清及4-羟基百菌清的残留... 目的建立气相色谱法(gas chromatography,GC)和液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)测定油麦菜及土壤中百菌清及4-羟基百菌清残留的方法,同时研究油麦菜及土壤中百菌清及4-羟基百菌清的残留降解规律。方法油麦菜和土壤中的百菌清分别采用乙腈溶液匀浆提取和振荡提取,使用固相萃取柱净化,气相色谱法带电子捕获检测器测定;油麦菜和土壤中的4-羟基百菌清分别采用乙腈溶液匀浆提取和振荡提取,氮吹至近干用甲醇复溶后过0.2μm滤膜净化,进LC-MS/MS测定分析。结果在0.01~5 mg/L范围内,百菌清及4-羟基百菌清均线性良好;在添加量均为0.01~1 mg/kg时,百菌清在油麦菜和土中的添加平均回收率分别为78.5%~79.8%、79.2%~82.4%,相对标准偏差(relative standard deviation,RSD)分别为3.01%~7.21%、5.06%~5.95%。4-羟基百菌清在油麦菜和土中的添加平均回收率分别为96.2%~116.7%、102.1%~113.9%,RSD分别为4.57%~6.22%、2.99%~4.57%。百菌清及4-羟基百菌清在油麦菜及土壤中的消解动态均符合方程C_t=C_(0e)^(-kt):百菌清在油麦菜中的半衰期为1.7 d,在土壤中半衰期为7.5 d,4-羟基百菌清在油麦菜中的半衰期为2.0 d,在土壤中半衰期为7.5 d。结论该方法简单快速,可同时测定百菌清及其代谢物,上述结果可为今后安全、合理、高效使用百菌清提供一定的参考价值。 展开更多
关键词 百菌清 4-羟基百菌清 液相色谱-串联质谱法 气相色谱法 残留降解
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披针新月蕨中的两个新黄烷苷 被引量:4
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作者 赵钟祥 金晶 +2 位作者 阮金兰 蔡亚玲 祝晨蔯 《药学学报》 CAS CSCD 北大核心 2008年第4期392-395,共4页
为了研究披针新月蕨的化学成分,采用不同色谱方法进行分离纯化,从披针新月蕨地上部分的正丁醇萃取部位分离得到2个化合物,根据光谱数据和理化性质进行结构鉴定,分别鉴定为4-′hydroxy pneum atopterin B(I)和6″-O-acetyl triphyllin A(... 为了研究披针新月蕨的化学成分,采用不同色谱方法进行分离纯化,从披针新月蕨地上部分的正丁醇萃取部位分离得到2个化合物,根据光谱数据和理化性质进行结构鉴定,分别鉴定为4-′hydroxy pneum atopterin B(I)和6″-O-acetyl triphyllin A(II)。化合物I和II为新化合物。 展开更多
关键词 披针新月蕨 黄烷苷 4-hydroxy pneumatopterin B:6″-O-acetyl triphyllin A
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鸡胗中百菌清及其代谢物残留量检测 被引量:2
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作者 陈美君 左海根 +4 位作者 刘小玉 张德继 王和雨 杜永琴 黄英杰 《安徽农业科学》 CAS 2022年第3期201-203,258,共4页
[目的]建立一种能同时检测鸡胗中百菌清及其代谢物4-羟基百菌清残留量的测定方法。[方法]鸡胗试样与无水硫酸钠混合后充分研磨,乙腈提取,浓缩定容后采用液相色谱仪测定。[结果]百菌清及其代谢物4-羟基百菌清在该色谱条件下得到很好的分... [目的]建立一种能同时检测鸡胗中百菌清及其代谢物4-羟基百菌清残留量的测定方法。[方法]鸡胗试样与无水硫酸钠混合后充分研磨,乙腈提取,浓缩定容后采用液相色谱仪测定。[结果]百菌清及其代谢物4-羟基百菌清在该色谱条件下得到很好的分离,百菌清和4-羟基百菌清浓度在0.05~1.00 mg/L呈较好的线性(R^(2)>0.999)。添加水平为0.02~0.08 mg/kg时添加回收率为74%~106%,相对标准偏差为1.6%~16.3%,方法定量限均为0.02 mg/kg。[结论]该方法具有样品前处理简单快速、灵敏度高、检测成本低的特点,可应用于鸡胗中百菌清及其代谢物4-羟基百菌清残留量的检测。 展开更多
关键词 百菌清 4-羟基百菌清 代谢物 残留 液相色谱仪
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改进的QuEChERS-高效液相色谱-串联质谱法同时测定蔬菜水果中百菌清及其代谢物残留 被引量:2
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作者 毕瑞锋 邓锁成 +2 位作者 付萌 张伟伟 张义霞 《农药学学报》 CAS CSCD 北大核心 2022年第2期429-434,共6页
建立了同时检测蔬菜水果中百菌清及其代谢物4-羟基百菌清的高效液相色谱-串联质谱分析方法。样品经酸化乙腈提取后,采用配备大气压化学电离源的三重四极杆串联质谱仪测定。结果表明:百菌清及其代谢物4-羟基百菌清在0.005~0.2 mg/L范围... 建立了同时检测蔬菜水果中百菌清及其代谢物4-羟基百菌清的高效液相色谱-串联质谱分析方法。样品经酸化乙腈提取后,采用配备大气压化学电离源的三重四极杆串联质谱仪测定。结果表明:百菌清及其代谢物4-羟基百菌清在0.005~0.2 mg/L范围内峰面积与质量浓度的线性关系良好,决定系数(R^(2))大于0.99;方法定量限为0.01 mg/kg。在0.01、0.05和0.2 mg/kg 3个添加水平下,百菌清及其代谢物4-羟基百菌清在结球甘蓝、黄瓜、葡萄和苹果4种基质空白样品中的平均回收率为83%~104%,相对标准偏差(RSD)为0.73%~7.7%(n=6)。该方法简单快速、准确可靠,适合蔬菜水果中百菌清及其代谢物4-羟基百菌清的定量测定。 展开更多
关键词 QUECHERS 高效液相色谱-串联质谱 大气压化学电离源(APCI) 百菌清 4-羟基百菌清 蔬菜水果
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MICROBIAL TRANSFORMATION OF 19-HYDROXY-CHOLESTEROL ACETATE OR 19-HYDROXY-β-SITOSTEROL ACETATE TO △~4-19-HYDROXY ANDROST-3, 17-DIONE
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作者 周维善 殷芝华 王敬一 《Chinese Science Bulletin》 SCIE EI CAS 1991年第16期1386-1387,共2页
The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or... The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or indirect synthesis via estrone of this class of compound. 展开更多
关键词 microbial transform ation 19-hydroxycholesterol ACETATE 19-hydroxy-β-sitosterol ACETATE △~4-19-hydroxy androst-3 17-dione.
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Palladium (0) Nanoparticles: A Novel and Reusable Catalyst for the Synthesis of Various Pyran Derivatives
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作者 Mithu Saha Amarta Kumar Pal 《Advances in Nanoparticles》 2012年第3期61-70,共10页
A ligand free, Palladium nanoparticles catalyzed synthesis of pyran derivatives using C-H activated compound, malononitrile and aryl aldehyde via Knoevenagel condensation followed by Michael addition reaction using Pa... A ligand free, Palladium nanoparticles catalyzed synthesis of pyran derivatives using C-H activated compound, malononitrile and aryl aldehyde via Knoevenagel condensation followed by Michael addition reaction using Palladium nanoparticles as catalyst in one-pot is described herein. The advantages of this method lie in its simplicity, low catalyst loading, cost effectiveness and easy to handle. The Palladium Nanoparticles can be reused without loss of activity even after recycling four times. The palladium nanoparticles were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM). The present method also allows us to synthesize highly functionalized title compounds from simple and readily available inputs. 展开更多
关键词 PALLADIUM NANOPARTICLES MULTI-COMPONENT Reaction PYRAN Derivatives DIMEDONE 4-hydroxy COUMARIN Pyranazolone
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Synthesis of a New Polymer-supported Reagent──Poly{[4- hydroxy(tosyloxy)iodo]styrene} and Its Application to the Synthesis of 2-Amino-4-arylthiazoles
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作者 黄宪 朱勍 张继振 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2002年第11期1411-1414,1133,共5页
A new polymer-supported reagent--poly{[4-hydroxy(tosyloxy)iodo]styrene} has good reactivity in the formation of 2-amino-4-arylthiazoles, and the procedure of regeneration and cycle are also described.
关键词 amino-4-arylthiazoles polymer supported reagents poly{[4-hydroxy(tosyloxy)iodo]styrene}
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