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排序方式: 共有153条查询结果,搜索用时 15 毫秒
1.
Schiff碱水杨醛苯甲酰腙的特性 总被引:3,自引:1,他引:2
研究了 Schiff碱水杨醛苯甲酰腙 (简称 SBH)晶体在 DMSO及其 DMSO- H2 O的混合溶剂中的红外光谱 ,通过 SBH氘代前后的 IR对比发现 ,羟基氢质子与混合溶剂 DMSO- H2 O(3∶ 1 ,V/ V)产生较大的相互作用。向溶有 SBH的 75 % DMSO- 2 5 % H2 O的溶液滴加 KOH发现 ,SBH分子上的 C O羰基基团先与 KOH作用 ,其后与 O H 羟基基团作用 相似文献
2.
Timofei S. Zatsepin Dmitry A. Stetsenko Tatiana S. Oretskaya 《Tetrahedron letters》2004,45(39):7327-7330
Oligodeoxyribonucleotides were synthesized that contain a novel nucleoside, 2′-O-(2-oxoethyl)arabinouridine. Whereas such oligonucleotides showed only a slight reduction in the TM values of their complexes with complementary DNA, a significant destabilization was observed in the case of duplexes formed with RNA. This may be explained by the C2′-endo conformation of 2′-O-(2,3-dihydroxypropyl)arabinouridine as demonstrated by NMR experiments in D2O. The modified oligonucleotides were used to synthesize a number of conjugates with dyes, biotin and a N-modified laminin peptide, by hydrazone and oxime formation. We suggest that the 2′-arabinoaldehyde-containing DNA duplexes may be valuable tools for affinity modification of DNA-binding proteins. 相似文献
3.
Paul Servin Régis Laurent Anne-Marie Caminade Jean-Pierre Majoral 《Tetrahedron letters》2007,48(4):579-583
A series of densely functionalized dendrimers is synthesized using two branched monomers of type AB2 and CD2, in which the A function (NH2) reacts with D (CHO) and the B function (Cl) reacts with C (OH). The reaction has been carried out up to the fourth generation possessing 96 end groups and has been obtained in only four steps. 相似文献
4.
5.
Vytautas Getautis Giedre Sinkeviciute Albina Stanisauskaite 《Monatshefte für Chemie / Chemical Monthly》2007,138(5):477-480
Summary. A synthesis of 1,2-diphenylpyrazolidin-4-ol via direct heterocyclization of 1,2-diphenylhydrazine with 1-chloro-2,3-epoxypropane, its O-epoxypropyl-, O-ethyl-, and O-benzylderivatives are described. Novel hydrazone derivatives with pyrazolidine units were also synthesized. The compounds
were characterized by spectroscopic methods as well as elemental analyses. 相似文献
6.
Synthesis of new diheteroarylcarbazoles: a facile and simple route of 3,6-di(pyrazol-4-yl)carbazoles
Ramu Meesala 《Tetrahedron letters》2006,47(43):7557-7561
A short and facile route to the synthesis of new 3,6-di(pyrazol-4-yl)carbazoles is reported. Dipyrazolylcarbazoles were synthesized in two steps from 3,6-diacetylcarbazoles through a Vilsmeier reaction which led to the formation of carbazolyl-β-chlorovinyl aldehydes, followed by cyclization with hydrazine hydrate. The reaction of the Vilsmeier reagent with hydrazones of diacetylcarbazoles yielded the corresponding pyrazole dicarbaldehydes in good yields. 相似文献
7.
Two diorganotin(IV) complexes of the general formula R2Sn[Ph(O)CCH-C(Me)N-NC(O)Ph] (R=Ph, 1; R=Me, 2) have been synthesised from the corresponding diorganotin(IV) dichloride and the ligand 4-phenyl-2,4-butanedionebenzoylhydrazone(2−) (H2L), derived from benzoyl acetone and benzoyl hydrazide in methanol at room temperature in presence of triethylamine. The syntheses were performed under very mild conditions, at room temperature and without exclusion of air or moisture from the reaction vessel. Previously, rigorous conditions have been considered necessary for these species. The two compounds have been characterised by elemental analysis, IR and 1H, 13C, 15N, 119Sn NMR spectra, and their structures have been confirmed single crystal X-ray structure analysis. The central tin atom of both complexes adopts a distorted trigonal bipyramidal coordination with two ligand oxygen atoms in axial positions, the nitrogen atom of the ligand and two organic groups on tin occupying equatorial sites. 2 has crystallised with two crystallographically independent molecules in the asymmetric unit. The δ(119Sn) values for the complexes 1 and 2 are −151.5 and −146.8 ppm, respectively, thus indicating penta-coordinated tin centres. 相似文献
8.
Anne-Marie Caminade Jean-Pierre Majoral Valérie Maraval Rosa-Maria Sebastián 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1493-1497
Several series of phosphorus-containing dendrimers have been designed to study the variation of their properties, depending on the type, the location (surface, branches, core, and cavities), and the number of functions implied. 相似文献
9.
Jian Wang Deyu Hu Linhong Jin Song Yang Baoan Song 《Journal of separation science》2013,36(3):602-608
A series of cis‐ and trans‐isomers of hydrazone derivatives were separated and analyzed through HPLC with diode‐array detection and HPLC‐MS/MS using ESI and ion trap MS. Two single crystals (A‐5‐1 and C‐2‐1) of the trans‐isomers were obtained and determined using X‐ray crystallography data, and the cis‐ to trans‐isomerization under different conditions was discussed. Both of the cis‐ and trans‐isomers of A‐4 and A‐5 exhibited good insecticidal activities against Plutella xylostella. 相似文献
10.
An asymmetric anti-aldol addition process of ketone-derived donors that is not limited by the structure of the ketone is described. This is achieved by merging the enantioselective α,α-bisalkylation of N-amino cyclic carbamate (ACC) hydrazones with the asymmetric anti-aldol addition of ACC hydrazones. The products of this process are obtained with essentially perfect stereoselectivity. Using this procedure it is possible to gain access to ketone-based anti-aldol addition products that are inaccessible in a controlled sense via direct aldol methods. 相似文献