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1.
A convenient approach for the preparation of (2S,3R,4R,5S,6R)-2-(3-(4-ethylbenzyl)-4-chlorophenyl)-6-(hydroxymethyl)- tetrahydro-2H-pyran-3,4,5-triol I is developed. The target compound via four steps is synthesized from 4-bromo-2-(bromomethyl)- 1-chlorobenzene and the isomers of undesired ortho-products were avoided during the preparation.  相似文献   

2.
3, 3-Dimethyl-1-(1,2,4-triazol)-2-butanone was treated with aqueous formaldehyde to give an additional product, and subsequent elimination by acetic anhydride yielded 4,4-dimethyl-2-(1,2,4-triazol)-1-penten-3-one. Further addition with substituted amines provideda series of (1,2,4-triazol)-4,4-dimethyl-3-pentanone, which were then reduced by KBH4 to obtaina series of (1,2,4-triazol)-4,4-dimethyl-3-pentanol. Their structures were confirmed by ^1HNMR and elemental analysis. The results of bioassay showed that the title products possess good fungicidal activities.  相似文献   

3.
The speciation in the phosphitomolybdate system, H+-MoO4(2-)-(HP)O(3)2-, has been determined from combined potentiometric and 31P NMR measurements in 0.600 M Na(Cl) medium at 298(1) K. Potentiometric titration data were collected in the ranges 2.5<-log[H+]<6.2, 40.0相似文献   

4.
Syntheses of (2S,4S)- and (2S,4R)-5-fluoroleucine, and, and of (2S,4S)-[5,5-(2)H(2)]-5-fluoroleucine, have been completed. The methodology allows these compounds to be prepared in sufficient quantities for incorporation by solid-state protein synthesis into strategic sites in proteins for folding studies. X-ray structures of the epimers and have been obtained and show the presence of conformational isomerism. The torsion angles between the F-C bond and the main chain are compared with values found in a mutant of the protein ubiquitin in which (2S,4S)-5-fluoroleucine replaces leucine residues 50 and 67 in the native protein.  相似文献   

5.
Some substituted 2-ethyl-3-(4-hydrazinocarbonylphenyl)-4-quinazolones and 2-ethyl-3-(4-hydrazinocarbonylmethylphenyl)-4-quinazolones were synthesized and characterized by their sharp melting points, elemental analyses and spectral data.  相似文献   

6.
Pan QJ  Fu HG  Yu HT  Zhang HX 《Inorganic chemistry》2006,45(21):8729-8735
The structures of [Pt2(pop)4]4-, [Pt2(pcp)4]4-, and related species [Pt2(pop)4X2]4- and [Pt2(pop)4]2- in the ground states (pop = P2O5H2(2-), pcp = P2O4CH4(2-), and X = I, Br, and Cl) were optimized using the second-order M?ller-Plesset perturbation (MP2) method. It is shown that the Pt-Pt distances decrease in going from [Pt2(pop)4]4- to [Pt2(pop)4X2]4- to [Pt2(pop)4]2-. This is supported by the analyses of their electronic structures. The calculated aqueous absorption spectra at the time-dependent density functional theory (TD-DFT) level agree with experimental observations. The unrestricted MP2 method was employed to optimize the structures of [Pt2(pop)4]4- and [Pt2(pcp)4]4- in the lowest-energy triplet excited states. The Pt-Pt contraction trend is well reproduced in these calculations. For [Pt2(pop)4]4-, the Pt-Pt distance decreases from 2.905 A in the ground state to 2.747 A in the excited state, which is comparable to experimental values of 2.91-2.92 A and 2.64-2.71 A, respectively. On the basis of the excited-state structures of such complexes, TD-DFT predicts the solution emissions at 480 and 496 nm, which is closer to the experimental values of 512 and 510 nm emissions, respectively.  相似文献   

7.
New liquid-crystalline 2-(4-cyanophenyl)-5-(4-alkyl- and alkoxyphenyl)pyridines were obtained by condensation of 1-dimethylamino-3-dimethylimmonia-2-(4-alkyl- or alkoxyphenyl)-1-propene perchlorates with 4-cyanoacetophenone and subsequent conversion of the 1-dimethylamino-2-(p-alkyl- or alkoxyphenyl)-4-(p-cyanobenzoyl)-1,3-butadienes to 5-(4-alkyl- or alkoxyphenyl)-2-(4-cyanophenyl)pyrylium perchlorates and refluxing of the latter with ammonium acetate in acetic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1392–1394, October, 1985.  相似文献   

8.
A series of single-chain magnets, [Mn2(saltmen)2Ni(pao)2(L)2](A)2 (saltmen(2-)=N,N'-(1,1,2,2-tetramethylethylene) bis(salicylideneiminate), pao-=pyridine-2-aldoximate; A-=ClO4- with L=4-picoline; 2, 4-tert-butylpyridine; 3, N-methylimidazole; 4, and L=pyridine with A-=BF4-; 5, PF6-; 6, ReO4-; 7), was prepared by reactions between MnIII dimer units, i.e., [Mn2(saltmen)2(H2O)2](A)2 (A-=ClO4-, BF4-, PF6-) or Mn2(saltmen)2(ReO4)2, and NiII monomeric units, i.e., Ni(pao)2(L)2, in methanol/water media. The crystal structures of 4, 6, and 7 were established by single-crystal X-ray crystallography. These three compounds are isostructural with [Mn2(saltmen)2Ni(pao)2(py)2](ClO4)2 (1) (Clérac, R.; Miyasaka, H.; Yamashita, M.; Coulon, C. J. Am. Chem. Soc. 2002, 124, 12837) and crystallize in monoclinic space group C2/c. The linear arrangement of MnIII dimer units and NiII building blocks leads to an alternating chain having a repeating unit, [-(O)2-Mn-ON-Ni-NO-Mn-]. The chains are well separated with the nearest interchain intermetallic distance of 10.36 A for 4, 10.51 A for 6, and 10.30 A for 7, and there is no significant pi-pi interchain interaction between ligands. The void space between the chains is occupied by counteranions, which control the three-dimensional organization of the chains. The X-ray diffraction analysis (XRD) on a powder sample was also performed for all compounds. The XRD patterns for 1, 2, and 4-7 are very similar, emphasizing the isostructural nature of these materials although they have individually slight different interchain distances. Inversely, the XRD pattern for 3 reveals a completely different shape being indicative of the peculiar crystal packing compared to the others. Nevertheless, the one-dimensional nature of the structure is also kept in 3 as indicated by magnetic measurements. The whole family of compounds exhibits quasi-identical magnetic behavior compared to that described for 1. Above 30 K, the heterometallic chain can be described as an assembly of antiferromagnetically coupled Mn...Ni....Mn trimers (via oximate bridge, -24.2 K相似文献   

9.
Summary NiII and CuII complexes of 2-acetylpyridine 4 N-(2-methylpyridinyl)-, 4 N-(2-ethylpyridinyl)- and 4 N-methyl(2-ethylpyridinyl) thiosemicarbazones (HL4pam, HL4pae, and HL4Mpae, respectively) of general formula [M(HL)X2] have been isolated from boiling EtOH and characterized by physico-chemical and spectroscopic methods. The growth inhibition activities of the thiosemicarbazones and their complexes were measured against Aspergillus nicer and Paecilomyces variotii.  相似文献   

10.
用中压汞灯(λ > 300 nm)照射4-苯乙烯基吡啶、2-苯乙烯基苯并噁唑和5-苯基-2-苯乙烯基噁唑三种杂芳基乙烯单体中任意两种的硫酸水溶液,得到三种交叉二聚体.用高效液相色谱跟踪研究了交叉光二聚反应,发现每组反应生成三种光二聚体,其中二种为单体自身的光二聚体,而另外一种是两种不同单体的交叉光二聚体.交叉二聚体通过柱色谱分离得到,其顺式头对尾结构经紫外、红外、氢谱、碳谱和元素分析确定.用紫外光谱和高效液相色谱跟踪研究了交叉光二聚体的稀溶液在低压汞灯(λmax=254 nm)照射下的光解反应.研究发现交叉二聚体能够彻底发生光解,首先生成原来的反式单体,所生成的反式单体容易发生异构化而生成顺式单体,最终建立起反顺异构化平衡.  相似文献   

11.
(2S,3S)-[3-(2)H1]-4-Methyleneglutamic acid 1a and (2S,3R)-[2,3-(2)H2]-4-methyleneglutamic acid 1b have been synthesised for use in biosynthetic and metabolic studies.  相似文献   

12.
By a reaction of 2-methyl-4-chloroquinolines with o-mercaptoaniline under various conditions synteses were performed of substituted in the benzene ring 4-[(2-aminophenyl)thio]-2-methylquinolines and (4E)-4-[(2-mercaptophenyl)imino]-2-methyl-1,4-dihydroquinolines that were respectively by isomerization or rearrangement converted into 4-[(2-mercaptophenyl)amino]-2-methylquinolines.  相似文献   

13.
In order to study the difference in microscopic orientation of ferro- and antiferroelectric liquid crystalline molecules, we synthesized the partially deuteriated chiral compounds, (S)-(-)-2-methylbutyl 4-(4-(d13)-hexyloxy- and (S)-(-)-2-methylbutyl 4-(4-(d17)-octyloxy-phenyl)benzoates. Fundamental physical properties such as phase transition temperatures, spontaneous polarization and tilt angle were determined. Polarized FTIR measurements were also made to provide information on molecular structure and orientation.  相似文献   

14.
In situ generated 2,4-diaryl substituted münchnones from 2-(4-substitutedphenyl)-2-(N-methyl-N-4-substitutedbenzamido)acetic acids react with acetic anhydride in the presence of 2-nitromethylene thiazolidine, which is most likely acting as a base, and unexpectedly undergo a Dakin–West type reaction and a concurrent autoxidation reaction leading to the formation of (E)-1-(N,4-dimethylbenzamido)-1-(4-fluorophenyl)prop-1-en-2-yl acetate, 4-substitutedphenyl-N-methyl-N-(4-substitutedbenzoyl) benzamides and p-substituted benzoic acids. In addition, a novel and efficient access to N-acyl urea derivatives is described by the reaction between 2-(4-substitutedphenyl)-2-(N-methyl-N-4-substitutedbenzamido)acetic acids and cyclohexyl, isopropyl carbodiimides in the presence of a base. The structures of all new products were identified on the basis of NMR and IR spectra, along with X-ray diffraction data and HRMS measurements.  相似文献   

15.
Two new 1-substituted 4-(2-phenylquinazolin-4-yl)-and 4-(2-phenylquinazolin-4-ylidene) thio-semicarbazides were formed by a multistep domino reaction of imidoyl isothiocyanate derivative with 1,1-di-R-hydrazine in acetone solution. Application of hydrazine hydrate under the same reaction conditions afforded 4-(2-phenylquinazolin-4(3H)-ylidene)-2-(propen-2-yl)-1-(propan-2-ylidene) thio-semicarbazide via a six-step triple-component domino reaction. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1688–1693, November, 2008.  相似文献   

16.
《Liquid crystals》2000,27(11):1437-1443
In order to study the difference in microscopic orientation of ferro- and antiferroelectric liquid crystalline molecules, we synthesized the partially deuteriated chiral compounds, (S)-(-)-2-methylbutyl 4-(4-(d13)-hexyloxy- and (S)-(-)-2-methylbutyl 4-(4-(d17)-octyloxy-phenyl)benzoates. Fundamental physical properties such as phase transition temperatures, spontaneous polarization and tilt angle were determined. Polarized FTIR measurements were also made to provide information on molecular structure and orientation.  相似文献   

17.
张建兴  黄德音 《有机化学》1996,16(2):157-159
异氰酸苯酯和N-[2-(4, 6-二甲基)-嘧啶基]-羟胺(5)反应生成1-[2-(4, 6-二甲基)-嘧啶基]-1-羟基-3-苯基脲(6)。化合物(6)在三乙胺存在下和氯甲酸乙酯反应生成2-[2-(4, 6-二甲基)-嘧啶基]-4-苯基-1, 2, 4-恶二唑烷-3, 5-二酮(1)。  相似文献   

18.
Synthesis was performed of 4-(4-ethoxycarbonylphenylamino)- and 4-(2-carboxyphenylamino)-2-methylquinolines by reaction of 2-methyl-4-chloroquinoline with anesthesin and anthranilic acid. In concentrated sulfuric acid 4-(2-carboxyphenylamino)-2-methylquinoline underwent cyclization into 6-hydroxy-7-methylquinolino[3,2-c]quinoline, and the alkaline hydrolysis of 4-(4-ethoxycarbonylphenyl-amino)quinoline afforded 2-methyl-4-(4-carboxyphenylamino)quinoline.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 786–787.Original Russian Text Copyright © 2005 by Avetisyan, Aleksanyan, Ambartsumyan.  相似文献   

19.
2-(4-Pyridyl)-1,3,5-triazine, 2-(4-pyridyl)-4-methyl-1,3,5-triazine, 2-(4-pyridyl)-4,6-dimethyl-1,3,5-triazine and 2-(4-pyridyl)pyrimidine have been prepared by modification of established triazine and pyrimidine syntheses. These compounds and some of their relatives have been converted to quaternary pyridinium salts. The polarographic reduction potentials of the salts in aqueous solution are pH dependent. The activity of the salts as post-emergent herbicides is reported.  相似文献   

20.
2- and 4-(2-Methylquinolin-4-ylamino)benzoic acids and ethyl 4-(2-methylquinolin-4-ylamino)-benzoates having a substituent in the 6(8)-position of the quinoline ring were synthesized by reaction of the corresponding substituted 4-chloro-2-methylquinolines with 2- and 4-aminobenzoic acids and ethyl 4-aminobenzoate. Intramolecular cyclization of 2-(2-methylquinolin-4-ylamino)benzoic acids in concentrated sulfuric acid gave 7-hydroxy-6-methyldibenzo[b,h][1,6]naphthyridines, and ethyl 4-(2-methylquinolin-4-ylamino)benzoates were converted into 4-(2-methylquinolin-4-ylamino)benzoic acids by alkaline hydrolysis.  相似文献   

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