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1.
环己胺与手性元5-(R)-(1′R,2′S,5′R)-孟氧基-3-溴-2(5H)-呋喃酮的不对称M ichael加成/分子内亲核取代反应,得到含有两个新手性中心的氮杂环丙烷/稠合丁内酯标题化合物。对其进行了谱学表征和X-射线单晶衍射测定。标题化合物分子式为C20H33NO3,M r=335.47,三斜晶系,P1空间群,晶胞参数:a=5.438(11)。A,b=8.117(2)。A,c=11.572(2)。A,α=96.84(3)°,β=94.48(3)°,γ=101.86(3),°V=493.5(2)。A3,Z=1,D c=1.129g/cm3,R=0.0867,wR=0.2344。 相似文献
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《Tetrahedron: Asymmetry》2000,11(9):1919-1925
The synthesis of (R)- and (S)-7,7′-dimethoxy-2,2′-bis(diphenylphosphino)-1,1′-binaphthalene 5a and 5b is described. The phosphorus atoms in (S)-(−)-5b are shown to be slightly more basic than the phosphorus atoms in (S)-BINAP by comparing the magnitude of the 1J (31P–77Se) coupling constant in their respective diselenide derivatives. (S)-(−)-5b behaved similarly to (S)-BINAP in asymmetric Heck reactions. 相似文献
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《Tetrahedron: Asymmetry》1998,9(2):285-292
The title compound 3, an intermediate in the synthesis of fluorocarbapenems, is obtained with high stereocontrol by the condensation of (R)-(+)-ethyl 4,4,4-trifluoro-3-hydroxybutanoate with N-trimethylsilyl cinnamylidenimine. X-Ray diffraction analysis of the condensation product and chemical correlations allowed the unambiguous determination of the absolute configuration. 相似文献
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An unsaturated 2-methoxy-substituted 1-O-alkylglycerol, (Z)-(2′R)-1-O-(2′-methoxynonadec-10′-enyl)-sn-glycerol, a new analog of bioactive ether lipids, was synthesized from oleic acid and 2,3-isopropylidene-sn-glycerol. The two key steps of this synthesis were the conversion of oleyl aldehyde to a monounsaturated epoxide using Matteson’s method followed by hydrolytic kinetic resolution and a nucleophilic epoxide opening by 2,3-isopropylidene-sn-glycerol in the presence of potassium tert-butoxide in anhydrous DMF, which appeared to be a good reagent for this purpose. Furthermore, the diol by-product of the HKR process was also easily converted back to the starting epoxide thus almost doubling the amount of target molecule. 相似文献
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Kuo Hsiung LEE 《中国化学快报》2005,(10)
In our prior studies,3′,4′-di-O-(S)-camphanoyl-(+)-cis-khellactone(DCK,1,Figure1)and its derivatives including mono-and di-substituted DCK analogs were identified as a novel class of potent anti-HIV agents1-4.Because of its high potency and efficient syn-thesis,4-methyl-DCK25was chosen as a drug candidate for preclinical studies.How-ever,the low solubility and poor oral bioavailability of4-methyl-DCK limited its further development.Because high molecular hydrophobicity might be one re… 相似文献
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《Polyhedron》2002,21(27-28):2711-2717
Schiff bases obtained from N,N′-(1R,2R)-1,2-cyclohexanediamine and 2-hydroxy-3-methylbenzaldehyde, 2-hydroxy-5-methylbenzaldehyde, have been used as ligands for copper(II), cobalt(II) and nickel(II). The complexes were characterized with UV–Vis, circular dichroism (CD), infrared, diamagnetic and paramagnetic 1H NMR spectroscopy. CD spectra revealed exciton coupled π→π* transitions. Assignments of LMCT and d–d transitions in CD spectra of Ni(II), Co(II) and Cu(II) complexes is proposed. CD data are characteristic for central ion tetrahedral distortion from the planarity and λ conformation of the cyclohexane ring. 1H NMR of Ni(II) complexes exhibited significant coordination shifts of CHN and ring protons which are in the closest proximity to Ni(II). The 1H NMR paramagnetic spectra of Co(II) complexes revealed the most upfield shifted resonance at −60 ppm assigned to CHN and −28 ppm to hydrogen atom at C(5′) of the phenyl ring. Results of spectral analyses suggest central ions in a distorted square-planar geometry with N2O2 chromofore group. 相似文献
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Edward Szlyk Stanislaw Biniak Erik Larsen 《Journal of Solid State Electrochemistry》2001,5(3):221-226
The electrochemical properties and catalytic activity of a Co(II) complex with the optically active Schiff base derived from
(1R,2R)-(–)-cyclohexanediamine and salicylaldehyde have been studied in non-aqueous solutions. When dissolved in deoxygenated non-aqueous
solutions, the complex exhibits reversible redox properties for the Co(II)/Co(III) couple. Electrochemical reduction of oxygen
and oxidation of cobalt(II) was observed on cyclic voltammograms of solutions containing both dioxygen and the Schiff base-cobalt(II)
complex. An anodically formed film on a platinum electrode, studied by means of X-ray photoelectron spectroscopy, revealed
the presence of the oxidized Co(III) species. Cyclic voltammetry of oxygenated solutions examined after a period of time indicates
an electrochemical activity of coordinated superoxo/peroxo species in the 0.7–1.1 V potential range. In the presence of 4-methyl-1-cyclohexene
the cyclic voltammetry curves reveal changes similar to those caused by the removal of oxygen. The GC-MS technique was used
to identify some of the products formed by the catalytic oxidation of cyclohexene and 4-methyl-1-cyclohexene.
Electronic Publication 相似文献
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Russian Chemical Bulletin - Alkylation of 5-(3,3-R,R′-2-oxido-1-triazeneoxymethyl)tetrazole salts with iodomethane, dimethyl sulfate, chloroacetonitrile, and... 相似文献
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Rail R. Gataullin Zulfia R. Zileeva Marina A. Maksimova Liana F. Zainullina Yuliya V. Vakhitova 《Journal of heterocyclic chemistry》2020,57(3):1236-1248
N-tosyl-2- and N-tosyl-4-halogen-substituted derivatives of 2-(1-methylbut-2-en-1-yl)aniline were synthesized and their molecular iodine-mediated cyclization was investigated. The cyclization upon interaction of N-tosyl-6-methyl-2-(1-methylbut-2-en-1-yl)aniline with molecular iodine in methyl tert-butyl ether or acetonitrile was studied, as well as the interaction of this sulfonamide with N-bromosucinimide in dichloromethane. Synthesized (2R*,3R*)- and (2R*,3S*)-N-arylsulfonyl-2-(1-halogenoethyl)-3-methylindoline derivatives showed cytotoxic activity against HEK293 cells, SH-SY5Y, Jurkat, and HepG2 cell lines. The compounds (2R*,3S*)-N-arylsulfonyl-7-bromo-2-(1-halogenoethyl)-3-methylindoline cis- 4a , stereoisomeric (2R*,3R*)-trans- 4h and (2R*,3S*)-N-tosyl-7-chloro-2-(1-halogenoethyl)-3-methylindoline cis- 4h demonstrated selective toxicity against SH-SY5Y cell line (IC50 ≈ 3 ÷ 5 μM), and did not affect HEK293, Jurkat, and HepG2 cells. 相似文献
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Krushna C. Satpathy Ashok K. Panda Rushabha Mishra Aditya P. Chopdar Sarada K. Pradhan 《Transition Metal Chemistry》1991,16(6):628-630
Summary Binuclear metal complexes of the type [M(HMTE)-(H2O)2]2, where HMTE=1-(-hydroxynaphthyl)-2-(3-methyl-5-mercapto-1,2,4-triazolc)2-aza-ethane and M-CuII, CoII, NiII and MnII have been prepared and characterized. An octahedral geometry around the metals is proposed. The complexes have been screened as possible fungicides. 相似文献
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《Polyhedron》1987,6(2):285-288
Some new U(VI) and Ce(IV) complexes of 1-(2′-hydroxybenzyl)-2-(2′-hydroxyphenyl)-benzimidazole have been prepared and characterized by spectrg magnetic and conductance studies. IR spectral data suggests that the ligand in all the complexes is monodenate through the tertiary nitrogen and that the phenolic oxygen is free from coordination. Conductivity measurements indicate that the nitrate and acetate complexes of U(VI) are non-electrolytes, whereas the nitrate complex of Ce(IV) is a 1:1 electrolyte. 相似文献
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邻羟基二苯甲酰基甲烷与Ac2O和HC(OEt)3反应通常是HC(OEt)3作为酰化剂,得到3-苯甲酰基色酮。本文报道5-甲氧羰基-2-羟基苯甲酰基-(2′-甲氧苯甲酰基)甲烷与Ac2O和HC(OEt)3反应时,是Ac2O而不是HC(OEt)3作为酰化剂,生成3-苯甲酰基-2-甲基色酮。其结构经NMR、MS、IR和EA证实。并对其反应机理作了讨论。 相似文献
18.
《Tetrahedron: Asymmetry》2001,12(15):2099-2102
A synthesis of the enamine (−)-(1′S)-5-ethyl-1-(1′-phenylethyl)-1,2,3,4-tetrahydropyridine 4 and its application in a synthesis of (−)-(1′S,4aS,8aR)- and (+)-(1′S,4aR,8aS)-4a-ethyl-1-(1′-phenylethyl)-octahydroquinolin-7-ones 5 and 6 is described. In addition, an X-ray study of 6 is reported. Finally, the preparation of (+)-(4aS,8aR)-4a-ethyl-octahydroquinolin-7-one 7 is described. 相似文献
19.
The synthesis of the title compound is described. The key-step is the photochemical coupling between 5-iodo-2-thienylcarbaldehyde and 2-bromothio-phene to give 5-bromo-2,2′-bithienyl-5′-carbaldehyde. 相似文献
20.
1-(5′-溴-2′-吡啶基)-5-4′-硝基苯基)-3-(2′-呋喃基)甲(月朁)的合成及其与锌显色反应的研究 总被引:2,自引:0,他引:2
甲■类试剂是有色金属离子的优良显色剂。它们的各种取代衍生物,有许多作为分析试剂已被研究。近年来,为了改善该类试剂的分析性能,在甲(?)骨架上接上吡啶、噻唑、眯唑及呋喃等杂环基团,合成了一系列不对称型的杂环甲(?)。 本文报导5-Br-PNPFF试剂的合成和提纯方法。研究了它与锌显色反应的条件,用 相似文献