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1.
本文采用元素分析、紫外吸收光谱、红外吸收光谱、质谱和核磁共振(NMR)波谱(包含1H NMR、13C NMR、DEPT、1H-1H COSY、1H-13C HSQC和1H-13C HMBC)等方法对德拉沙星葡甲胺进行了结构分析,确证了德拉沙星葡甲胺的结构,分析了其IR谱图特征吸收峰对应的基团,对其1H和13C NMR信号进行了完整归属.并通过差示扫描量热法、热重分析及粉末X-射线衍射分析对德拉沙星葡甲胺的晶型进行了初步研究.  相似文献   

2.
A series of 11 Schiff's bases derived from substituted salicylaldehyde and aliphatic amines has been studied in the solid state by 15N and 13C cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR). 15N CPMAS is especially useful for investigation of the tautomerism in the compounds considered, owing to the large difference in the nitrogen chemical shifts of OH and NH tautomers. In the solid state, three of the compounds examined were shown by 15N NMR to exist as OH tautomeric forms, and the remaining eight as the corresponding NH forms. This was confirmed by 13C CPMAS. The results reported were compared with those obtained in CDCl3 solutions.  相似文献   

3.
The 13C NMR solution spectra of 30-crown-10 ether and its tetrahydrate show only one resonance at all accessible temperatures. In contrast, the solid state 13C NMR spectrum of the 30-crown-10.4H2O shows two resonances in the ratio of 4:1, separated by 1.2 ppm. In the case of 30-crown-10 itself, six resolvable 13C resonances in the ratio of 4:1:1:2:1:1 are observed in the solid with an overall chemical shift dispersion of 5 ppm. The remarkably different spectral behavior of these two systems in the solid state is discussed in terms of the torsional environments of the crystallographically unique carbons and the results of GIAO calculations of isotropic 13C shieldings for simpler model compounds. Results of dipolar dephased 13C CPMAS spectra indicate that 30-crown-10 does not undergo a large amplitude molecular motion, in contrast to earlier results for 18-crown-6. Only a small amount of residual intensity is found in the dipolar dephased spectrum of 30-crown-10.4H2O, indicating that it also is relatively rigid in the solid.  相似文献   

4.
用红外吸收光谱、紫外吸收光谱、核磁共振(NMR)波谱(包含1H NMR、13C NMR、DEPT135、1H-1H COSY、1H-13C HMQC和1H-13C HMBC)、质谱、差示扫描量热分析、X-射线粉末衍射和元素分析等方法对卢立康唑进行了结构分析.对卢立康唑所有的1H和13C NMR信号进行了归属,并通过多种谱学技术确证了卢立康唑的结构.  相似文献   

5.
镜煤吡啶不溶物及其热解加氢产物的NMR研究   总被引:1,自引:0,他引:1  
本文对镜煤吡啶不溶物、热解加氢后吡啶及四氢呋喃不溶物进行了固体NMR研究,获得了12种结构参数,并对热解加氢产物中的苯可溶各馏份进行了一维、二维液体NMR研究,归属了其13C和1H谱,计算了各馏份的平均分子结构.  相似文献   

6.
盐酸马尼地平是第三代合成降压新药.本文利用一维、二维核磁共振(NMR)技术,包括1H NMR、13C NMR DEPT-135、1H-1H NOESY、1H-1H COSY、1H-13C HSQC和1H-13C HMBC,对其1H和13C NMR信号进行了全归属,进一步确证了其分子结构.同时,对其1H NMR和13C NMR谱中一些异常信号进行了讨论.  相似文献   

7.
Two Schiff bases; NN′-bis(5-bromosalicylidene)-1,2-diaminoethane, BS, and 7-[(1-{5-bromo-2-hydroxyphenyl} methylidene)amino]-4-methylcoumarin, Sc, and two appropriate Schiff–Mannich bases, NN′-bis{5-bromo-3-[(diethylamino)methyl]salicylidene}-1,2-diaminoethane, BSM, and 7-[(1-{5-bromo-3-[(diethylamino)methyl]-2-hydroxyphenyl} methylidene)amino]-4-methylcoumarin, SMc, capable of intramolecular hydrogen bonding have been investigated by multinuclear magnetic resonance methods in both solid and liquid phases. In all of the compounds under investigation tautomeric equilibrium involving an intramolecular hydrogen bond has been found. The Schiff–Mannich bases, which can form two different kinds of H bonds at room temperature, form relatively weak H bonds with the imino nitrogen atoms. At low temperatures the tautomeric proton exchange becomes slow on the NMR time scale and both hydrogen-bonded forms can be observed by 1H, 13C, and 15N NMR methods. In the solid state the tautomeric process is frozen and only one H-bonded form is present. On the basis of 13C and 15N CPMAS NMR spectra this is identified as the form with hydrogen bonds involving the imino groups. This conclusion is in good agreement with previous results obtained by X-ray diffraction methods.

The investigated Schiff bases (BS and Sc) form relatively weak H bonds. The proton position in the hydrogen bridge, estimated from 15N and 13C chemical shifts, is very similar in both the solution and solid phases. In chloroform solution the observed tautomeric equilibria are almost insensitive to a temperature change within the range 223 to 303 K.  相似文献   


8.
The solid state 13C CPMAS NMR spectra of plant cell walls are often complex owing to superposition of resonances from different polysaccharides and the heterogeneity of the cell wall assembly. In this paper, we describe the application of a set of proton relaxation-induced spectral editing (PRISE) experiments which combine 1H relaxation properties (T1, T, T2) with 13C high resolution spectroscopy (CPMAS) to relate the dynamics of the plant cell walls and model systems to their domain structural details. With PRISE it has been found that in plant cell wall materials, cellulose is always associated with the long components of spin–lattice relaxation in both the laboratory and rotating frames whereas non-cellulose polysaccharides (pectin and hemicellulose) are associated with the short ones. For the proton T2 relaxation, cellulose is only associated with the short component (below 20 μs), pectin contributes to both the short component and the long one.  相似文献   

9.
本文测定了α-溴代丙烯酰胺与丙氨酸反应产物的1H,13C-NMR谱,采用NMR的各种技术对其谱线进行归属,鉴定出该产物的化学结构,是氮丙啶化合物的一对等量的非对映异构体的混合物,并讨论了1H,13C-NMR谱与立体化学的关联。本文测定的氮丙啶化合物的非对映异构体的13CNMR谱未见报道。  相似文献   

10.
由于谱峰拥挤和重迭、关附庚素的一部分1H和13C谱峰用一般核磁共振方法难于确定归属。本工作采用选择性远程DEPT、一维COSY和-维接力COSY等新技术作了研究,其1H和13C谱峰归属全部得到确定。结果有助于此类化合物的化学结构测定。  相似文献   

11.
盐酸贝西沙星是一种新型的氟喹诺酮类抗菌药物,对盐酸贝西沙星的紫外吸收光谱(UV)、红外吸收光谱(IR)、质谱(MS)、核磁共振(NMR)波谱(包括1H NMR、13C NMR、DEPT、HSQC、HMBC、COSY和NOESY)数据进行了解析,对其所有的1H和13C NMR信号进行了归属,通过多种波谱学技术确证了盐酸贝西沙星的结构.  相似文献   

12.
用2D NMR研究凯林内酯酰化物的相对构型   总被引:3,自引:1,他引:2  
孔令义  吕扬 《波谱学杂志》1993,10(4):433-440
用2D NMR对钙离子拮抗活性成分Pd-Ia的结构进行了深入研究,确切归属了全部碳氢信号,纠正了文献中甲基信号归属的错误。并以此为参考,指定了这类化合物母核碳信号的归属,从而修正了文献中用角甲基碳化学位移值之差决定其C-3'和C-4'相对构型的有关内容,发现在顺式构型中,连接在C-2'的两个角甲基碳化学位移差值大于或等于2ppm,而在反式构型中,这个差值小于或等于2ppm,且△(δC-3'trans-δC-3'cis)>1ppm。  相似文献   

13.
涂光忠  梁鸿 《波谱学杂志》1993,10(3):281-286
本文利用了多种NMR技术,其中包括1H 13C NMR,DEPT、COSY、C,H-COSY、COLOC和NOE差谱,首次确定了圆果皂甙元的结构及构型。  相似文献   

14.
从湖北蟹甲草根茎中分得一个新的生物碱,选择性远程DEPT 13C NMR新技术用于识别NMR信号归属和连接被季碳及杂原子分割的质子自旋系统,确定其结构为新阔叶千里光碱的氮氧化物,如(1)所示。  相似文献   

15.
通过1H NMR、NOE差谱和门控去偶13C NMR等的研究确定了新合成的五对α-去氢氨基酸衍生物的构型,并利用部分弛豫、APT 13C NMR二维碳氢相关谱及13C-19F偶合常数等对NMR谱线进行了归属.  相似文献   

16.
采用1H-1H COSY、NOESY、1H-13C HMQC及HMBC二维NMR技术鉴定了2个新合成的4β-5- 氟尿嘧啶取代-4′-去甲表鬼臼毒衍生物, 并对它们的1H和13C NMR 谱峰进行了全归属.  相似文献   

17.
吴达旭  沈旭 《波谱学杂志》1998,15(6):547-550
利用1H-1H COSY,1H-13C HMQC,HMBC等2D NMR技术对一种新的配体1-(2-羧基苯基甲酰基)氨基硫脲(H3L)进行1H、13C NMR谱数据分析与归属,对于它与Cu+离子配位的化合物[Cu2(H3L)2Cl2](H2O)3也作了1H、13C NMR的测定,简单讨论了它的配位行为,粗略确定了它的结构.  相似文献   

18.
丁氟螨酯是一种新型杀螨剂,具有高效、低残留的特点.本文对其红外吸收光谱(IR)、紫外吸收光谱(UV)、质谱(MS)及核磁共振(NMR)波谱(包括1H NMR、13C NMR、DEPT、1H-1H COSY、1H-13C HSQC、1H-13C HMBC)进行了测定,分析了其UV和IR谱图特征吸收峰对应的基团,并对其1H和13C NMR信号进行了归属,确证了丁氟螨酯的结构.该研究将为丁氟螨酯的其他相关研究提供参考.  相似文献   

19.
Prudent analysis of the solid state 13C MAS NMR spectra of polycrystalline K2Pt(CN)4 · 3H2O (KTCP) reveals that in crystals of this compound there are two types of carbon nuclei with slightly different 13C chemical shift tensors, contrary to what is found for the solution NMR spectrum and previous static powder NMR studies on this compound and the high resolution solid state NMR studies on other similar compounds. The 13C MAS spectra measured at different rotor spinning speeds are satisfactorily simulated though the use of a newly developed computer program based on a novel density matrix formulation. The present method is eminently successful even though the spectra are rather complicated because of (1) the relatively large anisotropies of the chemical shift tensors; (2) the high-order dipolar interactions between 13C and 14N nuclei because of the strong quadrupolar coupling constants of 14N nuclei; and (3) the indirect J-coupling between the 13C and 195Pt. The principal elements as well as their orientations of the two 13C chemical shift tensors are evaluated from the spectral simulations.  相似文献   

20.
报道标题化合物的NMR谱,利用1H,13C NMR和DEPT等技术确定新化合物的化学结构,并归属了所有质子和碳的化学位移.  相似文献   

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