共查询到18条相似文献,搜索用时 491 毫秒
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通过以2-对羟基苯基-2-噁唑啉为中间体,可以成功地从对羟基苯甲酸甲酯或对羟基苯甲酸乙酯出发合成一种新型的功能性助剂—2-(4-环氧丙氧基苯基)-2-噁唑啉,其结构经1H NMR及13C NMR检测为所设计的目标结构。该结构具有110℃的熔点。 相似文献
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采用新方法合成了紫外线吸收剂苯基-(3,5-二叔丁基-4-羟基苄基)丙二酸二(1,2,2,6,6-五甲基-4-哌啶)酯。苯基丙二酸二乙酯和N-甲基-2,2,6,6-四甲基-4-哌啶醇在甲苯中微纳米碳酸钾催化下反应,得到苯基丙二酸二(1,2,2,6,6-五甲基哌啶醇)酯,然后在乙醇中与 4-羟基-3,5-二叔丁基苄基氯反应,得到目标产物,总收率为80%。化合物的结构通过1H NMR和13C NMR进行了表征。 相似文献
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为精确表征六烯丙基六氮杂异伍兹烷(HAIW)的化学结构,在氘代氯仿(CDCl3)及氘代丙酮(acetone-d6)中研究了HAIW的核磁谱图特征。采用一维及二维1 H、13 C、15 N NMR技术对HAIW的NMR信号进行了全归属,利用核磁模拟软件NMR-SIM对氢谱图进行计算机拟合。结果表明,HAIW在丙酮溶液中的1 H NMR的分辨率较好,谱图中存在两类异伍兹烷信号(环内与桥头)及两类烯丙基碳氢信号,其中五元环所连4个烯丙基不能自由旋转导致亚甲基氢不对称出现2组峰,而六元环所连2个烯丙基则能自由旋转使得该亚甲基氢对称重合;两类烯丙基存在的多种偶合使得氢谱谱线较为复杂;由拟合氢谱化学位移及偶合常数获得的1 H NMR谱图与实际图谱完全一致。表明二维核磁共振技术与核磁模拟技术相结合,可用于对复杂谱的精确分析。 相似文献
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本文从氨基蔥醌出发设计合成了苯基取代蔥醌衍生物,并运用^1H NMR,^13C NMR以及MS进行表征。 相似文献
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设计了以无水苯为溶剂,双标记尿素-(~(13)C,~(15)N_2)和丙炔酸为原料进行环化反应,粗品经脱色和重结晶后得到双标记尿嘧啶-(~(13)C,~(15)N_2)。在Ar气氛下,双标记尿嘧啶-(~(13)C,~(15)N_2)和1-乙酰氧基-2,3,5-三苯甲酰氧基-β-D-呋喃核糖反应,经处理后得到的中间体1-(2,3,5-三苯甲酰氧基-β-D-呋喃核糖基)尿嘧啶-(~(13)C,~(15)N_2)用氨水水解,即可得到双标记尿嘧啶核苷-(~(13)C,~(15)N_2)。该方法操作简单,中间体只需简单纯化,各步反应收率高,并且~(13)C、~(15)N同位素丰度不被稀释。产物经高效液相色谱法(HPLC)、MS、~1H NMR和~(13)C NMR表征,结果表明,双标记尿嘧啶核苷-(~(13)C,~(15)N_2)质量分数98%,~(15)N同位素丰度98%,~(13)C同位素丰度98%。 相似文献
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Dr. Vlastimil Jirasko Dr. Nils-Alexander Lakomek Dr. Susanne Penzel Dr. Marie-Laure Fogeron Prof. Dr. Ralf Bartenschlager Prof. Dr. Beat H. Meier Dr. Anja Böckmann 《Chembiochem : a European journal of chemical biology》2020,21(10):1453-1460
Proton-detected 100 kHz magic-angle-spinning (MAS) solid-state NMR is an emerging analysis method for proteins with only hundreds of microgram quantities, and thus allows structural investigation of eukaryotic membrane proteins. This is the case for the cell-free synthesized hepatitis C virus (HCV) nonstructural membrane protein 4B (NS4B). We demonstrate NS4B sample optimization using fast reconstitution schemes that enable lipid-environment screening directly by NMR. 2D spectra and relaxation properties guide the choice of the best sample preparation to record 2D 1H-detected 1H,15N and 3D 1H,13C,15N correlation experiments with linewidths and sensitivity suitable to initiate sequential assignments. Amino-acid-selectively labeled NS4B can be readily obtained using cell-free synthesis, opening the door to combinatorial labeling approaches which should enable structural studies. 相似文献
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Li Y Berthold DA Frericks HL Gennis RB Rienstra CM 《Chembiochem : a European journal of chemical biology》2007,8(4):434-442
DsbB is a 20 kDa Escherichia coli inner-membrane protein that catalyzes disulfide-bond formation in periplasmic proteins. We report highly resolved, multidimensional magic-angle spinning NMR spectra at 750 MHz (1)H frequency, which enable partial (13)C and (15)N chemical-shift assignments of the signals. The narrow line widths observed indicate excellent microscopic order of the protein sample, suitable for full structure determination by solid-state NMR. Experiments were performed exclusively on uniformly (13)C,(15)N-labeled DsbB. Chemical-shift-correlation experiments based on dipolar transfer yielded strong signals in the 3D spectra, many of which have been site-specifically assigned to the four transmembrane helices of DsbB. Significant numbers of additional residues have been assigned to stretches of amino acids, although not yet placed in the amino acid sequence. We also report the temperature dependence of signal intensities from -50 degrees C to 0 degrees C, a range over which samples of DsbB are highly stable. Structural and dynamic information derived from SSNMR studies can give insight into DsbB in a state that so far has not been successfully crystallized. 相似文献
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氯代嘌呤的加氢脱氯反应研究 总被引:5,自引:1,他引:4
采用w(Pd)=5% 的PdC为催化剂,V(水) V(乙醇) =1∶1 的混合液为溶剂,对6 氯 9 苄基 9H 嘌呤、6 氯 9 四氢吡喃 2 基 9H 嘌呤和6 氯 2 氨基 9 苄基 9H 嘌呤等氯代嘌呤衍生物的加氢脱氯反应进行了研究,在反应温度为室温,H2 压力为303kPa,催化剂用量为反应物质量的15% ,反应时间3h 的较佳工艺条件下,产品收率大于90% 。用1 H NMR、13 C NMR和MS对产物进行了表征 相似文献
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利用微量有机元素分析仪、红外光谱仪、核磁共振波谱仪鉴定了一种从杀菌防霉剂中分离出来的新型有机溴类杀菌剂,并且应用1D和2D核磁共振技术包含1H、13C、DEPT、1H—1HCOSY、HSQC、HMBC 6种NMR分析测试方法,对该杀菌剂的结构进行了确定,对其1H、13C信号进行了归属。 相似文献
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The solution behaviour of the square-planar gold(III) complex [Au(dien)Cl]Cl(2) (dien = 1,5- diamino-3-azapentane) was investigated by (13)H and (13)C NMR spectroscopy. We have found that (1)H NMR spectra of [Au(dien)Cl] Cl(2) are characterised by exchange behaviour over the whole pH range, and some exchange effects are also seen in (13)C NMR spectra of the deprotonated hydroxo derivative of the complex in alkaline solution. An exchange rate of > 378 s(-1) was determined from (1)H NMR spectra at pH *(2) (coalescence temperature (40)C degrees ). In slightly acidic solutions of the complex, (1)H chemical shifts are in accordance with the known deprotonation of the central amine group of the complexed diethylenetriamine ligand. In (13)C NMR spectra, two separate sets of resonances are observed for the chloro and the hydroxo complex of gold(III) diethylenetriamine. The hydroxo complex [Au(dien-H)OH(+) shows exchange effects in (13)C NMR spectra. Variable temperature studies show the carbon atoms next to the central secondary amine to be inequivalent and each present in two different environments that are in intermediate to fast exchange on the NMR time-scale. 相似文献