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1.
Summary. Conformational analysis and frequency calculation were achieved for 1-phenyl-1,2-propandione 1-oxime and its four tautomers: 1-nitroso-1-phenyl-1-propen-2-ol, 1-nitroso-1-phenyl-2-propanone, 2-hydroxy-1-phenyl-propenone oxime, and 3-nitroso-3-phenyl-propen-2-ol. Calculations were carried out at the Hartree–Fock (HF), Density Functional Theory (B3LYP), and the second-order M?llerPlesset perturbation (MP2) levels of theory using 6-31G* and 6-311G** basis sets. Five conformers with no imaginary vibrational frequency were obtained by free rotations around three single bonds of 1-phenyl-1,2-propandione-1-oxime: Ph–C(NOH)C(O)CH3, PhC(NOH)–C(O)CH3, and PhC(N–OH)C(O)CH3. Similarly, eight structures with no imaginary vibrational frequency were encountered upon rotations around three single bonds of 1-nitroso-1-phenyl-1-propen-2-ol: Ph–C(NO)C(OH)CH3, PhC(N–O)C(OH)CH3, and PhC(NO)C(–OH)CH3. In the same manner, six minima were found through rotations around three single bonds of 1-nitroso-1-phenyl-2-propanone: Ph–CH(NO)C(O)CH3, PhCH(–NO)C(O)CH3, and PhCH(NO)–C(O)CH3. Also, two minima were found through rotations around four single bonds of 2-hydroxy-1-phenyl-propenone oxime: Ph–C(NOH)C(OH)CH2, PhC(N–OH)C(OH)CH2, PhC(NOH)–C(OH)CH2, and Ph-C(NOH)C(–OH)CH2. Finally, two minima were found through rotations around four single bonds of 3-nitroso-3-phenyl-propen-2-ol: Ph–CH(NO)C(OH)CH2, PhCH(–NO)C(OH)CH2, PhCH(NO)–C(OH)CH2, and PhCH(NO)C(–OH)CH2. Interconversions within the above sets of conformers were probed through scanning (one and/or two dimensional), and/or QST3 techniques. The order of the stability of global minima encountered was: 1,2-propandione-1-oxime > 1-nitroso-1-phenyl-2-propanone > 1-nitroso-1-phenyl-1-propen-2-ol > 2-hydroxy-1-phenyl-propenone oxime > 3-nitroso-3-phenyl-propen-2-ol. Hydrogen bonding appears significant in tautomers of 1-nitroso-1-phenyl-1-propen-2-ol and 2-hydroxy-1-phenyl-propenone oxime. The CIS simulated λmax for the first excited singlet state (S1) of 1-phenyl-1,2-propandione 1-oxime is 300.4 nm, which was comparable to its experimental λmax of 312.0 nm. The calculated IR spectra of 1-phenyl-1,2-propandione 1-oxime and its tautomers were compared to the experimental spectra.  相似文献   

2.
TlAgS, TlAgSe and TlAgTe crystallize with the orderedanti-PbCl2-structure type, space group Pnma,Z=4. The lattice constants are: TlAgS:a=722.8(3).b=446.6(1),c=833.1(2)pm. TlAgSe:a=747.56(3),b=463.75(2),c=869.0(1) pm. TlAgTe:a=775.9(1),b=486.8(1),c=877.3(2) pm. The crystal structure of TlAgSe was refined from single crystal diffractometer data to a conventionalR-factor of 0.045. The relationship with the BaCu2S2-structure type is discussed.On leave from Institute of Inorganic Chemistry, University of Vienna A-1090, Wien, Austria  相似文献   

3.
Propylenediamine and trimethylenediamine have been found to form mixed complexes with Cd(II) in aqueous medium with stoichiometries 1:1:1 and 1:1:2. The overall formation constants of these mixed complexes have been evaluated usingSchaap andMcMaster's method. The tendency of the complexes (simple and mixed) to add and substitute another ligand is discussed.
Polarographische Untersuchungen an gemischten Komplexen von Cd(II) mit Propylendiamin und Trimethylendiamin
Zusammenfassung Propylendiamin und Trimethylendiamin bilden in wäßr. Lösung gemischte Komplexe mit Cd(II) in den stöchiometrischen Zusammensetzungen 1:1:1, 1:1:2 und 1:2:1., Die Bildungskonstanten dieser Komplexe wurden mit der Methode nachSchaap undMcMaster bestimmt. Die Tendenz der (einfachen und gemischten) Komplexe, mit anderen Liganden Addition oder Substitution einzugehen, wird diskutiert.
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4.
The crystal structure of NbMoN1–x has been determined from X-ray powder patterns. It is isotypic with the formerly described1,2 complex nitrides NbCrN and Ta1–x Cr1+x N. The tetragonal unit cell contains 6 atoms and belongs to the space groupP4/nmm-D 4h 7. The lattice parameters are:a=3,095 Å,c=7,799 Å. The structure is characterized by relatively close packed double layers of Nb-atoms and Mo-atoms parallel to the base plane. The nitrogen atoms are within the octahedral interstitial sites.
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5.
By means of potentiometric studies evidence was found for the formation of 1:1:1 ternary chelates of the type:M(III)-DTPA-dicarboxylic acids [M(III)=La(III), Pr(III), Nd(III), Gd(III) or Dy(III); dicarboxylic acids = phthalic acid (PHA) or malonic acid (MLA)]. The formation constants (logK MLL ) and free energies of formation (G°) have been evaluated. The order of stabilites with respect to the metal ions was La(III)MLA<PHA was observed.
Gemischte Chelate einiger Selten-Erd-Metalle mit Diethylentriamin-pentaessigsäure und Dicarbonsäuren
Zusammenfassung Es wurden ternäre 1:1:1-Chelate folgenden Typs mittels potentiometrischer Untersuchungen nachgewiesen:M(III)-DTPA-Dicarbonsäure [M(III)=La(III), Pr(III), Nd(III), Gd(III) oder Dy(III); Dicarbonsäure = Phthalsäure (PHA) oder Malonsäure (MLA)]. Die Komplexbildungskonstanten (K ML) und die Bildungsenthalphien (G°) wurden bestimmt. Bezüglich der Stabilität der Komplexe ergaben sich folgende Reihungen: La(III)MLA<PHA.
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6.
Summary. Ethyl 2-(N-morpholinyl)cyclopent-1-ene-1-carboxylate reacted smoothly with cyanothioacetamide to give morpholinium 4-cyano-1-oxo-2,5,6,7-tetrahydro-1H-cyclopenta[c]pyridine-3-thiolate; the former when treated with N-benzyl-α-chloroacetamide gave either a S-alkyl derivative or cyclopenta[d]thieno[2,3-b]pyridine, depending on the reaction conditions. Under Mannich-type aminomethylation with primary amines and formaldehyde the above thiolate afforded derivatives of the previously unknown heterocyclic system, cyclopenta[g]pyrido[2,1-b][1,3,5]thiadiazine in 81–90% yields. Victor P. Litvinov, was Deceased Victor P. Litvinov, This paper is dedicated to the blessed memory of our colleague, Prof. Victor Petrovich Litvinov (Dec 24, 1932–Feb 26, 2007)  相似文献   

7.
Trimethylsilylacetamide and trimethylsilyltrifluoroacetamide react with halogenodiorganylboranes to monomeric or dimeric amidoboranes depending on the organyl substituents. The compounds were characterized analytically and spectroscopically (NMR:1H,19F,11B; MS; IR).
21. Mitt.:A. Meller, W. Maringgele, K. Hennemuth undU. Sicker, J. Z. anorg. allg. Chem., im Druck.  相似文献   

8.
Summary. Reaction of 1-(cyanoacetyl)-3,5-dimethylpyrazole with (E)-2-cyano-3-(het)arylprop-2-enethioamides was used for the synthesis of N-methylmorpholinium 3,5-dicyano-4-(het)aryl-6-oxo-1,4,5,6-tetrahydropyridine-2-thiolates for the first time. The latter were also obtained in a multicomponent one-pot mode via the condensation of cyanothioacetamide with corresponding aldehydes and above 1-cyanoacetylpyrazole in the presence of N-methylmorpholine under mild conditions. Thiolates 1 exist as a pair of cis/trans-diastereomers in different ratios (from 3:4 to 2:1). Last author was Deceased on February 26, 2007  相似文献   

9.
Summary. Methotrexate (MTX) is a folate antagonist used in treatment of several chronic inflammatory and neoplastic conditions. In this study, new MTX-like compounds that may-be potential anticancer agents were synthesized and their structures were determined by IR, UV, GC-MS, 1H NMR, and 13C NMR spectra. Also, in this study, a series structurally related to MTX or folate analogous compounds were evaluated whether they have inhibitory properties on the dihydrofolate reductase activity (DHFR).  相似文献   

10.
An X-ray crystal structure analysis of the title compound was carried out at –168°C in order to assign the stereochemistry around the oxirane: C25H49NO8Si2, trigonal, R3,a=25.18(1),c=13.55(1) Å (hexagonal axes),Z=9,d x =1.105.The structure was solved with direct methods and refined to anR-factor of 0.086.
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11.
Deprotonation of 3,4-dimethyl-3-pyrrolin-2-on (1) int-butyl alcohol/potassiumt-butoxide solutions takes place on the N atom, as shown by1H/2H exchange andpK a determinations of1 (pK=17.1), 1,3,4-trimethyl-3-pyrrolin-2-one (pK a =17.6), and 3,4-dimethyl-5-methoxy-2H-pyrrole (pK a =16.7). The SCF-MO approximation MINDO/3 indicates, however, that in the gas phase deprotonation of1 should occur at the C atom.
1.Mitt.:Ribó, J. M., Trull, F., Mh. Chem.110, 201 (1979).  相似文献   

12.
The reaction of galliumtrichloride and galliumtribomide resp. with 2,6-dimethyl- and 2,4,6-trimethyl-N-trimethylsilyl-trifluoroacetanilide leads to the trifluoracetanilidodihalogenogallanes1–3. The 2,6,9-trioxa-4,8-diaza-1,5-digalla-bicyclo-[3.3.1]-nonadiene derivatives1 a–3 a are formed probably as by products.N-Trimethylsilyltrifluoroacetamide reacts with galliumtrichloride to yield the trifluoroacetamido-dichlorogallane4.N-Trimethylsilyl-N,N,N-triorganyl-thioureas react with galliumtrichloride under elimination of chlorotrimethylsilane to give the thio-ureido-gallanes5 and6. IfN,N-diorganylureas andN,N-diorganyl-thio-ureas resp. are reacted with galliumtrichloride and methyl-gallium-dichloride resp., the thio-ureido- and ureido-gallanes7–9 are obtained by elimination of hydrogenchloride. The compounds are characterized by analysis and spectral data (NMR:1H,19F; MS; IR). The substances are monomeric in the gas phase, obviously due to internal coordination.
30. Mitt.:W. Maringgele undA. Meller, J. Organomet. Chem., im Druck.  相似文献   

13.
The results of kinetic and equilibrium experiments with the set of reaction of proton abstraction from 4-nitrophenyl[bis(ethylsulphonyl)]methane in acetonitrile are reported. Two strong organic bases are used: 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD). The rates of proton transfer reaction have been measured by T-jump method in the presence of perchlorate of the appropriate base as a common cation BH+ and supporting electrolyte-tetrabutylammonium perchlorate (TBAP) in the temperature range between 20–40°C are: k H =1.32×107−2.00×107 and 2.82×107−4.84×107 dm 3mol−1s−1 for MTBD and TBD respectively. The enthalpies of activation ΔH MTBD =13.5 and ΔH TBD =18.1 kJmol−1. The entropies of activation are negative: ΔS MTBD =−62.3 and ΔS TBD =−40.3 Jmol−1K−1. The change of the absorbance of the anion of 4-nitrophenyl[bis9ethylsulphonyl)]methane at the temperature 25°C in the presence of common cation BH+ gives the equilibrium constants K=705 and 906 M−1 for MTBD and TBD respectively. Kinetic and equilibrium results are discussed. The possible mechanism of proton transfer reaction between 4-nitrophenyl[bis(ethylsulphonyl)]methane and cyclic organic bases: MTBD and TBD in acetonitrile is proposed.  相似文献   

14.
The1H-NMR spin lattice relaxation times of aetiobiliverdin-IV- and biliverdindimethylester were determined using the inversion recovery technique. The relaxation times of protons attached to the terminal rings A and D are longer than those situated at the rings B and C which points to a higher mobility of rings A and D. Moreover these measurements allowed an independent assignment of the1H-NMR-signals of the methyl groups of biliverdindimethylester.
30. Mitt.:H. Falk undT. Schlederer, Ann. Chem., im Druck.  相似文献   

15.
Molecular mechanics (MM) methods were employed to evaluate stabilization upon formation of inclusion compounds between two different guest molecules and α- and β-cyclodextrins (CDs) for two different stoichiometries 1:1 and 1:2. The two guest molecules studied were n-alkyl carboxylic acids and n-alkyl p-hydroxy benzoates with variety of chain lengths. The computed stability for the inclusion compounds between α-CDs and n-alkyl carboxylic acids reproduced experimental data reported in the literature. The transition between 1:1/1:2 complexes occurred at an alkyl chain length of nC=9. It was previously demonstrated by diffusion coefficients measures that a stable 1:2 stoichiometry inclusion compound could be formed between n-alkyl p-hydroxy benzoates and α-CD for the chain length nC>4. The computed results reproduced the experimental ones. The combination between OPLS and GB/SA resulted in better agreements with experiments than those obtained with MM2 and MM3.  相似文献   

16.
The crystal structure of Pyridine-2,6-dithio-carbomethylamide (PDTA) is described: C9H11N3S2, monoclinic, P21/c,Z=4,a=6.000 (1) Å,b=8.840 (1) Å,c=21.452 (1) Å, =105.47 (1)o,d x=1.47 gcm–3. The structure was solved with direct methods and refined to a conventionalR-factor of 0.047. The molecule is nearly planar in the crystal. There are possibly weak intramolecular H-bonds between the two amide nitrogens and the pyridine nitrogen and intermolecular H-bonds between two amide nitrogens and one thioamide sulfur atom. The IR andRaman spectra ofPDTA and deuteratedPDTA are discussed.
Kristallstruktur und Schwingungsspektren von Pyridin-2,6-dithiocarbomethylamid
Zusammenfassung Die Kristallstruktur von Pyridin-2,6-dithiocarbomethylamid (PDTA) wurde bestimmt: C9H11N3S2, monoklin, P21/c,Z=4,a=6,000 (1) Å,b=8,840 (1) Å,c=21,452 (1) Å, =105,47 (1)o,d x=1,47 gcm–3. Das Phasenproblem wurde mittels direkter Methoden gelöst und die Struktur bis zu einemR-Faktor vonR=0,047 verfeinert. Das Molekül ist im Kristall nahezu planar. Das Vorliegen schwacher intramolekularer Wasserstoffbrücken zwischen den beiden Thioamid-Stickstoffatomen und dem Pyridinstickstoff sowie intermolekularer Wasserstoffbrücken zwischen Thioamid-Stickstoff- und Thioamid-Schwefelatomen wird postuliert. IR- undRaman-Spektren vonPDTA und deuteriertemPDTA werden diskutiert.
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17.
Summary. The stannides YNi x Sn2 (x = 0, 0.14, 0.21, 1) were prepared by arc-melting of the pure elements. They were characterized through X-ray powder and single crystal data: ZrSi2 type, space group Cmcm, a = 438.09(6), b = 1629.6(4), c = 430.34(7) pm, wR2 = 0.0607, 386 F 2 values, 14 variables for YSn2, CeNiSi2 type, Cmcm, a = 440.6(1), b = 1640.3(1), c = 433.0(1) pm, wR2 = 0.0632, 416 F 2 values, 19 variables for YNi0.142(7)Sn2, a = 441.0(1), b = 1646.3(1), c = 434.6(1) pm, wR2 = 0.0491, 287 F 2 values, 19 variables for YNi0.207(7)Sn2, and LuNiSn2 type, space group Pnma, a = 1599.3(3), b = 440.89(5), c = 1456.9(2) pm, wR2 = 0.0375, 1538 F 2 values, 74 variables for YNiSn2. The YSn2 structure contains Sn1–Sn1 zig-zag chains (297 pm) and planar Sn2 networks (307 pm). The stannides YNi0.142(7)Sn2 and YNi0.207(7)Sn2 are nickel filled versions of YSn2. The nickel atoms have a distorted pyramidal tin coordination with Ni–Sn distances ranging from 220 to 239 pm. New stannide YNiSn2 adopts the LuNiSn2 type. The nickel and tin atoms build up a complex three-dimensional [NiSn2] network in which the yttrium atoms fill distorted pentagonal and hexagonal channels. Within the network all nickel atoms have a distorted square pyramidal tin coordination with Ni–Sn distances ranging from 247 to 276 pm. Except the Sn4 atoms which are located in a tricapped trigonal Y6 prism, all tin atoms have between 4 and 5 tin neighbors between 297 and 350 pm. 119Sn M?ssbauer spectroscopic data of YNi x Sn2 show a decreasing isomer shift (from 2.26 to 2.11 mm/s) from YSn2 to YNiSn2, indicating decrease of the s electron density at the tin nuclei.  相似文献   

18.
The synthesis and reactions of methyl 2-[3-(trifluoromethyl)phenyl]-4H-furo[3,2-b]pyrrole-5-carboxylate (1a) are described. Upon reaction with methyl iodide, benzyl chloride, or acetic anhydride, this compound gave N-substituted products 1b-d. By hydrolysis of compounds 1a-c, the corresponding acids 2a-c were formed, or by reaction with hydrazine-hydrate, the corresponding carbohydrazides 3a-c were formed. By heating 2-[3-(trifluoromethyl)phenly]-4H-furo[3,2-b]pyrrole-5-carboxylic acid (2a) in acetic anhydride, 4-acetyl-2-[3-(trifluoromethyl)phenyl]furo[3,2-b]pyrrole (4) was formed. By hydrolysis of 4, 2-[3-(trifluoromethyl)phenyl]-4H-furo[3,2-b]pyrrole (5a) was formed, and reactions with methyl iodide or benzyl chloride gave N-substituted products 5b-c. The reaction of 4 with dimethyl butynedioate gave substituted benzo[b]furan 6. Compound 3a reacted with triethyl orthoesters giving 7a-c, which afforded with phosphorus (V) sulphide the corresponding thiones 8a-c. The thiones 8a-c reacted with hydrazine hydrate to form hydrazine derivatives 9a-c. The reaction of triethyl orthoformiate with compounds 9a-c led to furo[2′,3′: 4,5]pyrrolo[1,2-d][1,2,4]triazolo[3,4-f][1,2,4]triazines 10a-c. Hydrazones 11a-c were formed from 3a-c and 5-[3-(trifluoromethyl)phenyl]furan-2-carboxaldehyde. The effect of microwave irradiation on some condensation reactions was compared with “classical” conditions. The results showed that microwave irradiation shortens the reaction time while affording comparable yields.  相似文献   

19.
A convenient general method of preparing 4-acylpyridazines (4) is reported. It involves homolytic acylation of ethyl-4-pyridazinecarboxylate yielding ethyl-5-acyl-4-pyridazinecarboxylates (2) which easily can be converted to4 by alkaline hydrolysis followed by decarboxylation. The hitherto unknown pyridazino[4,5-d]pyridazine-1 (2H) ones bearing an alkyl- or arylsubstituent on C-4 (5a-g) were prepared in quantitative yields by reaction of2 with hydrazine.
10. Mitt.:G. Heinisch, A. Jentzsch undI. Kirchner, Tetrahedron Lett.1978, 619.  相似文献   

20.
Escherichia coli O157:H7 remains a continuous public health threat, appearing in meats, water, fruit juices, milk, cheese, and vegetables, where its ingestion at concentrations of perhaps as low as 10 to 100 organisms can result in potent toxin exposure and severe damage to the lining of the intestine. Abdominal pain and diarrhea develop, which in the very young or elderly can progress towards hemolytic uremic syndrome and kidney failure. To assist in the detection of E. coli O157:H7, a recombinant bacteriophage reporter was developed that uses quorum sensing (luxI/luxR) signaling and luxCDABE-based bioluminescent bioreporter sensing to specifically and autonomously respond to O157:H7 serotype E. coli. The bacteriophage reporter, derived from phage PP01, was tested in artificially contaminated foodstuffs including apple juice, tap water, ground beef, and spinach leaf rinsates. In apple juice, detection of E. coli O157:H7 at original inoculums of 1 CFU mL−1 occurred within approximately 16 h after a 6-h pre-incubation, detection of 1 CFU mL−1 in tap water occurred within approximately 6.5 h after a 6-h pre-incubation, and detection in spinach leaf rinsates using a real-time Xenogen IVIS imaging system resulted in detection of 1 CFU mL−1 within approximately 4 h after a 2-h pre-incubation. Detection in ground beef was not successful, however, presumably due to the natural occurrence of quorum sensing autoinducer (N-3-(oxohexanoyl)-l-homoserine lactone; OHHL), which generated false-positive bioreporter signals in the ground beef samples.  相似文献   

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