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1.
凤凰木种子毒蛋白的高效凝胶过滤色谱分析   总被引:1,自引:0,他引:1  
介绍用HPGFC(高效凝胶过滤色谱)对凤凰木种子中提取的3种毒蛋白分别进行色谱分析。并对分离的蛋白峰进行紫外光谱扫描来确认蛋白的纯度。根椐标准相对分子质量曲线,分别得到它们的相对分子质量并与SDS-PAGF(十二烷基磺酸钠-聚丙烯酰胺凝胶电泳)所得结果进行比较,用柱后衍生法测定了3个蛋白各自的氨基酸组成。  相似文献   

2.
植物白头翁毒蛋白的分离、纯化及其组分测定   总被引:4,自引:0,他引:4  
唐根源  张椿嵋  吴红京 《色谱》1998,16(5):414-416
植物白头翁(amenone)茎的抽提液经CM-SFF柱和SephacrylS-200柱分离纯化,得到一种毒蛋白,用高效凝胶蛋白柱和反相高效液相色谱法结合光电二极管阵列检测器确认分离峰的纯度,在高效凝胶蛋白柱上制备了少量毒蛋白纯样,测定了蛋白分子量和氨基酸组成。  相似文献   

3.
CONFORMATIONANALYSISOFGUANOSINE-5'-DIPHOSPHO-FUCOSEMinBoCHEN;YuLIU;ZhongWuGUO;GeQingCAI(ShanghaiInstituteofCrganicofOrganicCh...  相似文献   

4.
TOTAL SYNTHESIS OF CURVULARIN-TYPE MACROLIDES 12-OXOCURVULARIN AND CITREOFURANTOTALSYNTHESISOFCURVULARIN-TYPEMACROLIDES12-OXO...  相似文献   

5.
本文借助于IR,TG和XPS,研究了ZnO-SACF制备过程中及其吸附Ag^+和Au^3+前后的化学结构变化。实验结果表明:从SACF到ZnO-SACF,纤维表面上的O/C原子比和含氧基团如C=O和COO都有所减少;ZnO-SACF上还原性功能基团主要是-C-OH,当ZnO-SACF吸附Ag^+后,-C-OH被氧化为-C=O,而当其吸附Au^3+后,-C-PH被氧化为-C=O和-(O=C)-OH,  相似文献   

6.
ZEOLITE-CATALYZEDFRIEDEL-CRAFTSACYLATIONOFAROMATICS:Ⅲ.SYNTHESISOF4-ACYLANISOLEWITHUSYCATALYST¥YuDaoMA;QiLongWANG;XingDongJI;C...  相似文献   

7.
FLUORESCENCE STUDIES ON SELF-ASSEMBLING BEHAVIOR OF AMPHIPHILES WITH NAPHALENE-1,5-DIOXY GROUPFLUORESCENCESTUDIESONSELF-ASSEM...  相似文献   

8.
CATALYTIC PROPERTIES OF SILICA-SUPPORTED POLY-γ-AMINOPROPYLSILOXANE-RHODIUM-COBALT BIMETALLIC COMPLEX FOR HYDROFORMYLATIONCAT...  相似文献   

9.
CONVERSIONOFUNSATURATEDLONG-CHAINFATTYACIDSTO10-HYDROXYFATTYACIDSBYRESTINGCELLSOFNocardiasp¥.WeiHangCHAI;ZuYiLi(ShanghaiInsti...  相似文献   

10.
AFACILETOTALSYNTHESISOF6-PENTYL-α-PYRONE¥ChiZHANG;XueChaoWANG;FangNingZHANGandXinFuPAN(DepartmentofChemistry,StateKeyLaborato...  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

17.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

18.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

19.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

20.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

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