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1.

Abstract

A series of enantiomerically pure (Z)-(?)-4-(1′-alkyloxy-1′-alkyloxycarbonyl-methylidene)-5(R)-[(1R)-menthyloxy]-γ-butyrolactones were synthesized and characterized in good to excellent yields via O-alkylation of (4R,5R)-(?)-4-ethoxyoxalyl-5-[(1R)-menthyloxy]-γ-butyrolactone with alkyl halides in the presence of K2CO3 in acetone at room temperature.  相似文献   

2.
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   

3.
本文研究了1,10-双(1-苯基-3’-甲基-5’-氧代吡唑-4’-基)癸二酮-〔1,10〕从硝酸溶液中对Sc、Y、La的萃取分离。测定了固态萃合物的溶解性、摩尔电导、热稳定性及UV、IR、~1H NMR谱,讨论了萃合物的可能结构。  相似文献   

4.
《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   

5.
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   

6.
《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   

7.
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   

8.
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   

9.
10.
The stereochemistry of the asymmetric reduction of the imine obtained from 1,3-dimethylpiperidin-4-one and (S)--phenylethylamine has been studied. It is shown that hydride reduction of imine 1 by sodium borohydride in methanol is asymmetric and gives the cis and trans diastereomeric pair 1,3-dimethyl-4-(-phenyl-ethylamino) piperidine in the ratio 3:1. Using sodium in isopropanol gives only one trans diastereomeric pair.1H NMR has been used to identify the stereochemical structure and diastereomer excess of the cis and trans isomers of 1,3-dimethyl-4-(-phenylethylamino)piperidine which had been separated by column chromatography.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 219–221, February, 1996.  相似文献   

11.
Abstract: A three step synthesis of the advanced glycosylation endproduct 2-(2′-furoyl)-4(5)-(2′-furanyl)-1H-imidazole (4, FFI) has been achieved from 2-acetylfuran. The key step in the synthesis was the rearrangement of the hydrazinium bromide 3 in refluxing methanol.  相似文献   

12.
《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   

13.
An X-ray structural examination is carried out for 2,3-dimethyl-5-(2′-methylprop-1′-enyl)-6-(morpholyl-4′-carbonyl)-cyclohex-3-en-1-carboxlic acid that is one of the products of the Diels-Alder reaction of an acyclic monoterpene alloocimene with maleic and citraconic anhydrides followed by the ring opening of adducts with morpholine to corresponding amides. The crystals are triclinic; a = 10.619(1) ?, b = 12.784(2) ?, c = 14.328(2) ?; α = 65.752(1)°, β = 87.932(1)°, γ = 78.120(1)°; V = 1733.0(3) ?3, P-1 space group, Z = 4 (two independent molecules). In both molecules, the anti-conformation of the carboxylic group is observed, the conformation being stabilized by an intramolecular hydrogen bond involving the carboxylic hydrogen atom and ketonic oxygen.  相似文献   

14.
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   

15.
本文研究了Tb(Ⅲ)-1,4-双(′-苯基-3′-甲基-5′-氧代吡唑-4′-基)丁二酮-[1,4](BPMPBD)-溴化十六烷基三甲胺(CTMAB)体系的荧光性质,探讨了响影体系荧光性质的诸因素,确定了最佳实验条件。该体系中Tb(Ⅲ)浓度以2.0×10~(-5)~1.0×10~(-10)mol/L范围内与其荧光强度呈线性关系,检测限可达到5.0×10~(-11)mol/L。应用于合成样品中微量Tb(Ⅲ)的分析,结果令人满意。  相似文献   

16.
前言核苷三磷酸是含有两个高能磷酸键的高能化合物。除了参与核糖核酸合成外,在生物体内的生命活动中起着重要的作用。ATP 主要用于供给合成细胞的物质所需要的能量,也是被称为“第二信使”的环化AMP(3′5′-cyclicAMP)的前体。而后者已知与多种生化过程有关。CTP 参与重要磷脂类的合成。GTP 在蛋白质合成中是必不可少的。UTP 是肝脏中重要解毒剂尿二磷葡萄糖醛酸(UDPG)的前体,与肝糖元、酸性粘多糖的合成密切相关。根据已知的生理功能有些兄弟研究单位作了一些临床应用试验,还值得进一步探讨。  相似文献   

17.
The title compound (C26H20ClN3O3) has been synthesized by 1,3-dipolar cycloaddition reaction from isatin, sarcosine and (Z)-4-(4-chlorobenzylidene)-2-phenyloxazol-5(4H)-one through a one-pot procedure, and its structure was confirmed by IR, 1H NMR, elemental analysis and single-crystal X-ray diffraction analysis. The crystal belongs to the triclinic system, space group P1, with a = 9.3903(19), b = 11.398(2), c = 12.603(3) , α = 83.495(3), β = 68.988(3), γ = 67.178(3)°, V = 1160.1(4) 3, Z = 2, Mr = 457.90, Dc = 1.311 g/cm3, μ = 0.198 mm-1, F(000) = 476, the final R = 0.0489 and wR = 0.1144 for 3109 observed reflections with I > 2σ(I).  相似文献   

18.
The paper reported the synthetic procedure and character of Copper(Ⅱ) binuclear coordination compound of 1,4-bis-(1′-phenyl-3′-methyl-5′-pyrazolone-4′)-1,4-butanedione. The non-isothermal kinetic of the thermal decomposition of the complex has been studied from the TG-DTG curves by means of the Achar et al and Coats-Redfern methods. The electrochemical characterization of the complex were studied by means of powder microelectrodes technique.  相似文献   

19.
Interaction between hydroxyoxo(5,10,15,20-tetraphenylporphyrinato)molybdenum(V) and 2′-(pyridin-4-yl)-5′-(pyridin-2-yl)-1′-(pyridin-2-yl)methylpyrrolidinyl[60]fullerene in toluene has been studied by means of spectrophotometry. The reaction proceeds via two stages: rapidly established equilibrium between the reactants and their molecular complex 1: 1 [K = (1.97 ± 0.52) × 104 L/mol] followed by slow irreversible displacement of hydroxy group into the second coordination sphere to form cationic outer sphere complex (k = 0.26 L s?1 mol?1). The effect of fullerene fragment on pyridine fragments coordination has been considered.  相似文献   

20.
设计并合成了新化合物3,4-双(3′,5′-二硝基苯-1′-基)氧化呋咱(4)。以苯甲腈为起始原料,经加成、重氮化、分子间二聚得到3,4-二苯基氧化呋咱(3),3经HNO3/H2SO。硝化合成了4,其结构经^1H NMR,IR和元素分析表征;初步考察了加成、重氮化、缩合环化、硝化等反应的主要影响因素,确定了适宜的反应条件。  相似文献   

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