排序方式: 共有21条查询结果,搜索用时 93 毫秒
1.
Reaction of arenesulfonylimines of methyl trifluoropyruvate with 1,3-C,N-and-N,N-binucleophiles led to a variety of N-sulfonylated fluorine-containing heterocycles, including the fused ones.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2171–2175, November, 2007. 相似文献
2.
L. G. Lavrenova A. R. Amamchyan S. V. Larionov V. A. Dorokhov 《Russian Chemical Bulletin》1992,41(10):1810-1812
We have synthesized complex compounds of Co(2+) chloride with hydrochlorides of N-(1,2,4-triazol-5-yl)benzamidine and N-(tetrazol-5-yl)benzamidine. According to magnetochemistry and electron spectroscopy data, the ligands are coordinated in a bidentate fashion with the N atom of the amidine group and the N atom of the heterocycle with formation of the tetrahedral chromophore CoN2Cl2.Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk. N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2311–2315, October, 1992. 相似文献
3.
An efficient domino protocol for the synthesis of 1,2,4-oxadiazole derivatives from readily available 1-(2-oxo-2-arylethyl)pyridin-1-iums and amidine hydrochlorides was developed. In this practical approach, N-acyl amidine precursors were formed firstly via a simple nucleophilic substitution, without the purification of N-acylamidine intermediates, and the following intramolecularly dehydrative cyclization gave 1,2,4-oxadiazole derivatives in the presence of I2/K2CO3/DMSO, which exhibited excellent functional group tolerance and proceeded under simple experimental conditions. 相似文献
4.
We have constructed a number of benzamidine- and butylamine-based hydantoin compounds by means of an efficient route using
solid phase synthesis in which neat diisopropylamine was employed for a novel cyclization/traceless cleavage step. All library
compounds were obtained in excellent yield and high purity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Sulfated glycosaminoglycans were labeled with biotin to study their interaction with cells in culture. Thus, heparin, heparan sulfate, chondroitin 4-sulfate, chondroitin 6-sulfate and dermatan sulfate were labeled using biotin-hydrazide, under different conditions. The structural characteristics of the biotinylated products were determined by chemical (molar ratios of hexosamine, uronic acid, sulfate and biotin) and enzymatic methods (susceptibility to degradation by chondroitinases and heparitinases). The binding of biotinylated glycosaminoglycans was investigated both in endothelial and smooth muscle cells in culture, using a novel time resolved fluorometric method based on interaction of europium-labeled streptavidin with the biotin covalently linked to the compounds. The interactions of glycosaminoglycans were saturable and number of binding sites could be obtained for each individual compound. The apparent dissociation constant varied among the different glycosaminoglycans and between the two cell lines. The interactions of the biotinylated glycosaminoglycans with the cells were also evaluated using confocal microscopy. We propose a convenient and reliable method for the preparation of biotinylated glycosaminoglycans, as well as a sensitive non-competitive fluorescence-based assay for studies of the interactions and binding of these compounds to cells in culture. 相似文献
6.
氢键和极性相互作用在抑制剂-蛋白结合专一性识别过程中起到重要作用.抑制剂Benzamidine(BEN)与胰岛素trypsin相互作用机制的阐明有助于胰岛素高效抑制剂的研发.本文采用分子动力学模拟和MM-PBSA(molecular mechanics-Poisson Boltzmann surface area)从原子层次上研究BEN与胰岛素的结合模式.结果表明抑制剂BEN的脒基不仅与Asp189的羰基产生静电相互作用,而且与残基Ser190和Gly214形成氢键相互作用.基于残基能量分解的计算表明抑制剂的苯基与残基His58,Cys191,Gln192,Trp211,Gly212和Cys215形成有利于抑制剂结合的疏水性相互作用.期望当前的研究能为胰岛素有效抑制剂的研发提供重要的理论指导. 相似文献
7.
A novel and simple t‐BuOLi/I2‐mediated synthesis of 1,2,4‐trisubstituted imidazoles was developed without transition‐metal added. The transition‐metal‐free strategy tolerated a range of substrates and provided products in moderate to good yields with 100% regioselectivity. 相似文献
8.
A. S. Sagiyan A. E. Avetisyan S. M. Djamgaryan L. R. Djilavyan E. A. Gyulumyan S. K. Grigoryan N. A. Kuz'mina S. A. Orlova N. S. Ikonnikov V. S. Larichev V. I. Tararov Yu. N. Belokon 《Russian Chemical Bulletin》1997,46(3):483-486
Asymmetric synthesis of β-N-substituted (S)-α,β-diamino acids was accomplished by Michael addition of amines to the NiII complex of the Schiff base derived from (S)-2-[N-(N′-benzylprolyl)amino]benzophenone (BPB) and dehydroalamine. Diastereoselectivity of the reaction is kinetically and thermodynamically
controlled. The chiral auxiliary reagent, BPB, can be recovered and reused.
Translated fromIzvestiya Akademii Nauk. Serya Khimicheskaya, No. 3, pp. 504–507, March, 1997. 相似文献
9.
Sonia CantelDamien Boeglin Marc RollandJean Martinez Jean-Alain Fehrentz 《Tetrahedron letters》2003,44(25):4797-4799
Anchoring of an α-amino-acid amide residue by its amine function to a carbamate resin followed by primary amide Hofmann rearrangement led to a gem-diamino residue linked to the resin. The generated primary amine could be acylated with various carboxylic compounds offering a large variety of molecules. Furthermore, this new solid-phase strategy allowed a reliable synthesis of a gem-diamino monomeric residue which could not be easily obtained in solution due to the limited stability of monocarbamate-protected gem-diaminoalkyl derivatives. 相似文献
10.
Kai-Min Wu 《Tetrahedron》2005,61(41):9679-9687
Three pendant benzamidines [Ph-C(NC6H5)-{NH(CH2)2NMe2}] (1), [Ph-C(NC6H5)-{NH(CH2Py)}] (2) and [Ph-C(NC6H5)-{NH(o-C6H4)(oxazoline)}] (3) are described. Reactions of 1, 2 or 3 with one molar equivalent of Pd(OAc)2 in THF give the palladacyclic complexes [Ph-C{-NH(η1-C6H4)}{N(CH2)2NMe2}]Pd(OAc) (4), [Ph-C{-NH(η1-C6H4)}{N (CH2Py)}]Pd(OAc) (5) and [Ph-C{-NH(η1-C6H4)}{N(o-C6H4)(oxazoline)}]Pd(OAc) (6), respectively. Treatment of 4, 5 or 6 with excess of LiCl in chloroform affords [Ph-C{-NH(η1-C6H4)}{N(CH2)2NMe2}]PdCl (7), [Ph-C{-NH(η1-C6H4)}{N(CH2Py)}]PdCl (8) and [Ph-C{-NH(η1-C6H4)}{N(o-C6H4)(oxazoline)}]PdCl (9). The crystal and molecular structures are reported for compounds 1, 3, 5, 6 and 7. The application of these palladacyclic complexes to the Suzuki and Heck coupling reactions was examined. 相似文献