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1.
The starting material O‐protected glycosyl isothiocyanate ( 1?3 ) was refluxed with 1,4‐diaminobenzene in CHCl3 under nitrogen atmosphere to give 1,4‐bis(N‐glycosyl)thioureidobenzene ( 4?6 ). Then 1,4‐bis[N‐(4/6‐substituted benzothiazole‐2‐yl)‐N′‐glycosylguanidino]benzenes ( 8a?8e , 9a?9e , 10a?10e ) were obtained in good yield by reaction of compounds ( 4?6 ) with 2‐amino‐4/6‐benzothizoles ( 7a?7e ) and HgCl2 in the presence of TEA in DMF. The structures of all 18 new compounds were confirmed by IR, 1H NMR, LC‐MS and elemental analysis. The bioactivity of anti‐HIV‐1 protease (HIV‐1 PR) and against angiotensin converting enzyme (ACE) have been evaluated.  相似文献   

2.
Palladium(II) and platinum(II) complexes of N-ethyl-N′-pyrimidin-2-ylthiourea(HL1) and N-phenyl-N′-pyrimidin-2-ylthiourea (HL2) have been prepared, and the complexes [M(HL)Cl2], [Pt(L)2], [Pd(HL1)2]Cl2, and [Pd(L2)2] (where M = PdII or PtII) were characterized. The spectroscopic data are consistent with coordination of thioureas as neutral or monoanionic ligands to PdII and PtII through S and a pyrimidine-N. The IR spectra show shifts of CS and pyrimidine ring stretch bands to lower and higher frequencies, respectively. The 1H NMR spectra differentiate between H(4′) and H(6′) resonances and indicate downfield shifts for all protons of pyrimidine [H(4′), H(5′), and H(6′)], two resonances for two N?H protons for complexes containing the neutral ligand (HL), and only one N?H proton chemical shift for complexes containing the monoanion (L). 13C NMR chemical shifts of pyrimidine carbons are correlated with the type of bonding between PdII or PtII and pyrimidine-N. The magnetic susceptibilities suggest a diamagnetic planar structure for all complexes.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   

3.
The protonation of 4-methoxy-, 4-amino-, and 4-dimethylamino-6-aminopyrimido[4,5-b][1,4]thiazines and N-(4-methoxy-5-pyrimidinyl)acetamidine was studied by 1H and 13C NMR spectroscopy. It is shown that the addition of a proton in the first three compounds takes place at the N5 atom of the thiazine ring, whereas in the case of N-(4-methoxy-5-pyrimidinyl) acetamidine primary protonation is observed at the nitrogen atom of the amidine group, and the second proton adds to the N1 atom of the pyrimidine ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 49–54, January, 1979.  相似文献   

4.
Treatment of Pt(PPh3)4 with N,N‐dimethylthiocarbamoyl chloride, Me2NC(=S)Cl, in dichloromethane at ?20 °C processes the oxidative addition reaction to produce platinum complex [Pt(PPh3)21‐SCNMe2)(Cl)], 2 with releasing two triphenylphosphine molecules. The 31P{1H} NMR spectra of complex 2 shows the dissociation of the triphenylphosphine ligand to form diplatinum complex [Pt(PPh3)Cl]2(μ,η2‐SCNMe2)2, 3 in which the two SCNMe2 ligands coordinated through carbon to one metal center and bridging the other metal through sulfur. Complex 2 is characterized by X‐ray diffraction analysis.  相似文献   

5.
Condensation of bis(2-furanthiocarboxyhydradatometal(II), M(fth)2; [M (II) = Mn, Fe, Co, Ni, Cu and Zn] with pyridine-2- and -4-carboxaldehydes gave complexes of the formula M(pfth)2 [pfth? = pyridine-2-carboxaldehyde-2-furanthiocarboxyhydrazonato], Ni(Ifth)2, Zn(Ifth)2, Cu(Ifth) and Co(Ifth)3, (Ifth? = pyridine-4-carboxaldehyde-2-furanthiocarboxyhydrazonato). The magnetic and electronic spectral studies coupled with photoacoustic or Mössbauer spectra suggested octahedral geometry for the M(II) complexes with low-spin states for Co(Ifth)3 and Fe(pfth)2. IR and 1H NMR spectral studies of diamagnetic complexes suggested bonding through “azomethine” nitrogen and “thiolo” sulphur. IR spectra also showed the involvement of pyridine ring nitrogen in coordination in all the complexes except Cu(Itfh), Co(Ifth)3, and Zn(Ifth)2. Some of the compounds possessed antimicrobial activity.  相似文献   

6.
It has been established that the condensation of 3-(4-methoxyphenylamino)-5,6-dihydro-2H-1,4-oxazine with substituted phenacyl bromides occurs at the exocyclic nitrogen atom with formation of 3-aryl-3-hydroxy-1-(4-methoxyphenyl)-2,5,6,8-tetrahydro-3H-imidazo[2,1-c]-1,4-oxazinium bromides. By treatment of the latter with acetic anhydride 3-aryl-1-(4-methoxyphenyl)-5,6-dihydro-8H-imidazo[2,1-c]-1,4-oxazinium bromides are formed. The structures of the compounds synthesized were determined via 1H NMR spectroscopy and X-ray diffraction.  相似文献   

7.
New luminescent materials—aromatic polyketanils (PKs) containing p‐phenylene and biphenylene linkages in the backbone and electron‐donating, side‐group substitutions—were synthesized via melt polycondensation with the goal of studying the interactions between the polymer chains (PKs), primary dopant [1,2‐(di‐2‐ethylhexyl)ester of 4‐sulfophthalic acid (PSA)], and secondary dopant [m‐cresol (MC)] with 1H NMR, 13C NMR, Fourier transform infrared (FTIR), ultraviolet–visible, and photoluminescence measurements. Spectral changes were observed for the PKs after primary and secondary doping, and they supported ionic‐ and hydrogen‐bond formation between the PKs and the PSA and MC, respectively. This specific interaction of the dopant with the host polymer influenced the PK properties, and the following observations were made: (1) HOMO/LUMO energy gap of the protonated PKs; (2) bathochromic/hypsochromic photoluminescence shifts observed after protonation with PSA; (3) a downfield chemical shift of the labile proton in the protonating agent OH group in the 1H NMR spectra of the protonated polymers; (4) a protonation decrease in the intensity of the C?N stretching band in the FTIR spectrum; and (5) a spherulite‐like morphology, detected by atomic force microscopy and polarized optical microscopy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5645–5660, 2006  相似文献   

8.
Salicylaldehyde(N-benzoyl)glycyl hydrazone (SalBzGH) has been synthesized and characterized. Metal complexes of the empirical formula [Ln(SalBzGH-2H)OH(H2O)2] where Ln = Y, Pr, Nd, Sm, Eu, Gd and Dy, have been synthesized and their structures studied by infrared, far-infrared, absorption, emission and NMR spectra. 1H and 13C NMR spectra indicate the presence of dynamic equilibrium between two isomers of SalBzGH over the 298–368 K temperature range and stabilization of a single isomer upon complexation with Ln(III). The hypersensitive band profile of the Nd(III) complex indicates a change in metal coordination number due to solvation, while an increase of temperature results in a decrease of εmax of the hypersensitive band. The emission spectrum of [Eu(SalBzGH-2H)OH(H2O)2] at 77 K indicates a low site symmetry. SalBzGH coordinates through imidolic oxygen, azomethine nitrogen and phenolate oxygen.  相似文献   

9.
Dibromobenzimidazole and dibromoimidazole bearing hydroxyl group‐protected phenol unit ( 1 and 2 ) were prepared and they showed an intramolecular hydrogen bonding between ether oxygen and amino proton of imidazole. The palladium‐catalyzed Suzuki coupling polymerization of 1 and 2 with benzene bis(boronic acid) derivatives gave soluble polymers ( 3 and 4 ), where the molecular weights were limited probably due to the coordination ability of imidazole to palladium metal. The phenol hydroxyl groups were subsequently deprotected using BBr3 to obtain 3 ′ and 4 ′. From the 1H NMR spectra, the complete conversion to the hydroxyl group and the formation of another type of intramolecular hydrogen bonding between hydroxyl proton and imine nitrogen were confirmed. In the UV and PL spectra of 3 ′ and 4 ′, the excited state intramolecular proton transfer (ESIPT) occurred to shift the emission spectra toward lower energy region compared to 3 and 4 . Especially, the PL spectrum of 3 ′ demonstrated large stokes shift (145 nm) in THF solution. The ESIPT‐mediated fluorescence was influenced by the addition of methanol and trifluoroacetic acid, which inhibited the formation of intramolecular hydrogen bonding. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4822–4829, 2009  相似文献   

10.
In this study, we reported the synthesis of three kinds of mono-functional pillar[5]arene derivatives PRI, PRII and R and their structures were studied by 1D and 2D NMR spectra and mass spectra. The 2D NMR spectra including 1H-13C HSQC, 1H-1H COSY and NOESY spectra indicated that PRI and PRII are both stable self-included pseudo[1]rotaxanes in CDCl3. These original structures are promising compounds for the design of pillar[5]-based [1]rotaxane. And the results showed that R could exist stable in CDCl3 and DMSO because of the coordination of N-H?O hydrogen bonding interaction and C-H?π interaction.  相似文献   

11.
[M(4-epzdtc)2(py)], [M(4-epzdtc)2(1,10-phen)], and [M(4-epzdtc)2(2,2′-bipy)] (where M?=?Zn(II), Cd(II); 4-epzdtc??=?4-ethylpiperazinecarbodithioate) were synthesized and characterized by IR and NMR (1H, 13C, HSQC and HMBC) spectra. A single-crystal X-ray analysis was carried out for [Zn(4-epzdtc)2(py)]. The N13CS2 chemical shifts of [M(4-epzdtc)2] and its adducts follow the order: [M(4-epzdtc)2] (ca 202?ppm)?<?[M(4-epzdtc)2(py)] (ca 204?ppm)?<?[M(4-epzdtc)2(N,N)] (N,N?=?1,10-phen, 2,2′-bipy) (ca 206?ppm), due to the change in coordination number. Single-crystal X-ray structural analysis of [Zn(4-epzdtc)2(py)] showed that zinc is five-coordinate with four sulfurs from dithiocarbamate and one nitrogen from pyridine. This complex adopts a geometry intermediate between the tetragonal pyramid (C4v) and trigonal bipyramid (D3h). [Cd(4-epzdtc)2] and its adducts were used as single source precursors for preparation of CdS. The as-prepared CdS was characterized by powder X-ray diffraction, UV-Vis absorption, and fluorescence spectroscopy. The UV-Vis absorption spectra of CdS particles indicate a blue shift in the absorption spectra due to the quantum size effect.  相似文献   

12.
The 13C and 1H NMR spectra of (–)-bis[1R, 3 R, 4S]menthylphosphine (1) are assigned by two-dimensional double quantum NMR and 13C? 1H shift correlation diagrams. The variable temperature spectra of 1 indicate hindered rotation about the P? C bonds.  相似文献   

13.
1,4-二氢-4-芳基-3,5-吡啶二羧酸酯的合成及表征   总被引:1,自引:0,他引:1  
基于二氢吡啶化合物的构效关系, 设计了一系列1,4-二氢-4-芳基-3,5-吡啶二羧酸酯新化合物. 含有易于水解基团的1,4-二氢-4-芳基-3,5-吡啶二羧酸酯类化合物在碱性条件下水解合成了重要中间体1,4-二氢-4-芳基-3,5-吡啶二羧酸单酯, 收率93%~99.8%. 该二羧酸单酯与α-溴代芳基乙酮在相转移剂催化下反应合成目标化合物, 收率74%~99%. 中间体和目标化合物经1H NMR, 13C NMR, IR, MS和元素分析等确证.  相似文献   

14.
The isomeric tricyclo[4.4.1.12,5]dodecan-11-ols have been synthesized from the (6+4) cycloaddition product of tropone with cyclopentadiene. The configuration and conformation of each isomer was determined from the proton shift gradients induced in the olefinic proton signals in the 1H NMR spectra of intermediate compounds by Eu(fod)3.  相似文献   

15.
The tautomerism of the synthesized 3‐arylpyrimido[4,5‐c]pyridazine‐5,7(6H,8H)‐diones ( 1a–d ) and 3‐aryl‐7‐thioxo‐7,8‐dihydro‐6H‐pyrimido[4,5‐c]pyridazine‐5‐ones ( 2a–d ) was studied in dimethyl sulfoxide (DMSO)‐d6. 1H NMR spectra of 1a–d showed a clustered water molecule in the structure backbone that is attached by strong intermolecular H bonding. The relation between the temperature and H bonding of the clustered water molecule with 1a was also studied as representative. The relation between the electronegativity (χ) of the substituent on phenyl ring and the chemical shifts of clustered water protons in 1a–d was also studied. All of 1a–d and also 2d compounds existed in lactam ( I ) form, whereas 2a–c compounds have two distinguished tautomers in DMSO‐d6 [lactam ( I ) and lactim ( II ) forms]. The solvent‐substrate proton exchange was examined in compounds 1a–d and 2a–d by adding one drop of D2O. All compounds (except 1d ) showed proton/deuterium exchange of the clustered water protons in DMSO by adding one drop of D2O. Some compounds (but not all of them) that are easily soluble in DMSO‐d6 containing D2O showed isotopic splitting (β‐isotope effect) in their 13C NMR spectra. Among them, compound 1a was the best evidence to help the spectral assignments and structure determination of predominant tautomer by carbon‐13 splitting (β‐isotope effect). Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

16.
Data of 1H and 13C NMR spectra show that in 2,2??-bipyridyl, 1-vinyl-2(2??-pyridyl)benzimidazole, 1-vinyl-3-vinylsulfanyl-5-(2-furyl)-1,2,4-triazole, and 1-vinyl-5-vinylsulfanyl-3-(2-furyl)-5-vinylthio-1,2,4-triazole exists a weak intramolecular hydrogen bond between the heterocyclic fragments. It causes a downfield shift of the bridging proton signal in the 1H NMR spectrum by 0.6?C0.7 ppm and an increase in the corresponding direct coupling constant 13C-1H by 1.5?C2.0 Hz. These variations in the spectral parameters can be efficiently used in the conformational analysis for establishing with the use of NMR method which conformers are predominantly populated in the heterocyclic compounds.  相似文献   

17.
The intramolecular six-membered C–H?X (X=F, Cl, Br) hydrogen bonding motif of halogen-substituted 1,4-diphenyl-1,2,3-triazole compounds has been assessed. Twelve triazole derivatives have been designed and prepared, which bear fluorine, chlorine or bromine atoms on the ortho- and/or para-positions of the benzene rings. 1H NMR, X-ray crystallography, and DFT calculation investigations revealed that the ortho-fluorine, chlorine, and bromine atoms of the benzene ring on the C-4 of the triazole unit all can form six-membered C–H?X hydrogen bonding. In contrast, only fluorine forms similar, relatively stable intramolecular hydrogen bonding on the N-1 side of the triazole unit.  相似文献   

18.
The 13C NMR spectra of several 2-substituted imidazoles and benzimidazoles have been measured. The substituent was CH3, COOH and CONHR, where R = H, n-Bu, p-tolyl or m-chlorophenyl. Carbons 4 and 5 in the imidazoles and the carbon pairs 8/9, 4/7 and 5/6 become equivalent by proton transfer from N-1 to N-3, possibly through intermolecular association. The rate of this proton exchange increases with concentration and temperature. It decreases with extension of the 2-substituent (rate CH3?CONH-phenyl > CONH-p-tolyl ? CONH-m-chlorophenyl ? CONH-n-butyl) due to steric hindrance at the site of the (benz)imidazole nitrogen.  相似文献   

19.
Some 2-arylsulphonylamido-2-thiono-5-methyl-1,3,2-dioxaphospholanes (1), containing two chiral centres, give NMR spectra in which splittings of the 1H and 13C signals of the 5-methyl substituent and of the 31P signal indicate that they exist in an approximately 70:30% ratio of two racemic mixtures, Z and E respectively, diastereomeric to each other. These splittings were invariably observed for compounds 1a, containing a monosubstituted sulphonylamido group (Y = H) and various substituents at position 4′ of the aryl group, X = H, CH3, OCH3, F, CI and Br. The methylenic protons in position 4 of the phospholane ring are diastereotopic and therefore magnetically non-equivalent. Benzene-induced shifts were measured for the Z isomers of compounds 1a, X = H, F and for compound 1b, containing an N-disubstituted sulphonylamido group (Y = CH3) and X = H; the tentative interpretation of these shifts places the more shielded diastereotopic methylene proton on the same side of the ring as the 5-methyl substituent. The H? P and H? H coupling constants indicate that the preferred conformation of the dioxaphospholane ring should be a ‘twisted envelopey’ shape with the 5-methyl substituent in the equatorial position.  相似文献   

20.
Interaction of 2-aminothiophenol with β-aroylacrylic acids and their dibromo derivatives led to 2-(2-aryl-2-oxoethyl)-4H-benzo-1,4-thiazin-3-ones. The structure of synthesized compounds was confirmed by IR, 1H, and 13C NMR spectra and X-ray analysis.  相似文献   

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