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1.
M. T. Omar K. A. Kandeel A. S. A. Youssef 《Monatshefte für Chemie / Chemical Monthly》1995,126(4):439-446
Summary 3-Aryl-, 3-benzyl-, and 3H-5-(2-aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidines3a–h react with bromine in acetic acid solution to give mixtures of the respective 5-aroylmethylene (E) and (Z) diastereomeric derivatives5 and6. They contain more than 85% of the (E)-diastereomers along with some pure isomers. The intermediacy of the 5-bromo derivatives4 is proven and a plausible route of the reaction is presented. Structures of compounds3–6 are evidenced by analytical and spectral data.
Das Verhältnis von (E)- und (Z)-Isomeren bei der Reaktion von 5-(2-Aryl-2-oxomethyl)-2-thioxo-4-oxo-1,3-thiazolidinen mit Brom
Zusammenfassung 3-Aryl-, 3-Benzyl- und 3H-5-(2-Aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidine3a–h reagieren mit Brom in essigsaurer Lösung zu Gemischen der entsprechenden diastereomeren 5-Arylmethylen-Derivate ((E) und (Z))5 und6. Sie enthalten mehr als 85% des (E)-Diastereomeren. Die intermediäre Natur der 5-Brom-Derivate4 wird bewiesen; ein Reaktionsweg wird vorgeschlagen. Die Strukturen der Verbindungen3–6 werden durch analytische und spektroskopische Daten abgesichert.相似文献
2.
The reactions of sodium bis(2-methoxyethoxy)aluminum hydride with 3-cyano-6-methylpyridine-2(1H)-thione and 3-cyano-6-methyl-2-methylthiopyridine afforded 3-aminomethyl-6-methylpyridine-2(1H)-thione and azomethine of the pyridine series, respectively. The corresponding reaction with 3-cyano-4,6-dimethyl-2-methylthiopyridine gave rise to azomethine, substituted 3-aminomethylpyridine, and substituted dipyridylmethane. 相似文献
3.
A. I. Krivoshey N. S. Pivnenko S. V. Shishkina A. V. Turov L. A. Kutulya O. V. Shishkin 《Russian Chemical Bulletin》2006,55(6):999-1009
The spatial structure of (Z)-(5R)-methyl-2-(4-phenylbenzylidene)cyclohexanone prepared by photochemical isomerization of the E-isomer was studied by analyzing the magnitudes and temperature dependence of the proton spin-spin coupling constants obtained
by 1H NMR spectroscopy and the results of molecular modeling using semiempirical quantum chemical AM1 and PM3 methods and the
density functional theory (DFT). Comparison of the results obtained for the Z-and E-isomers shows that in both cases the conformational equilibrium for both isomers is characterized by significant preference
of the chair conformer having an equatorial methyl group, namely, − ΔH (chair a ⇌ chair e) = 1.98–2.12 and 1.36–1.54 kcal mole−1 for the Z-and E-isomers, respectively. Distinctions in the non-planarity of the enone fragment and cyclohexanone ring in the Z-and E-isomers under study following from the results of mathematical modeling were confirmed by the experimental values of the
geminal spin-spin coupling constants of protons of the methylene groups in α,α ′-positions with respect to the enone group.
Quantum chemical calculations of the Z-isomer revealed the existence of intramolecular hydrogen bond between the carbonyl oxygen and the nearest aromatic proton
in ortho-position of the benzene ring. Possible reasons for different helical twisting power of (Z)-(5R)-methyl-2-(4-phenylbenzylidene)cyclohexanone and the E-and Z-arylidene derivatives of 1R, 4R-isomenthone in the mesophase are discussed based on the results of molecular structure studies for these compounds.
In the text below the unsaturated ketones under study will be called “arylidene cyclohexanone derivatives” for convenience
of comparing the characteristics of methylcyclohexanone and isomenthone derivatives.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 962–972, June, 2006. 相似文献
4.
B. S. Fedorov N. I. Golovina V. V. Arakcheeva M. A. Fadeev G. V. Strukov V. V. Kedrov G. V. Shilov L. O. Atovmyan 《Russian Chemical Bulletin》1999,48(8):1584-1586
The reaction ofN,N′-bis(2-nitroxyethyl)pyridine-2,6-dicarboxamide with PdCl2 afforded previously unknowncis-(N-2-nitroxyethylpicolinamide-N,N′)dichloropalladium(II) andcis-[2-(2-pyridyl)-2-oxazoline-N,N′]dichloropalladium(II), which were isolated as a cocrystallizate of the molecular compounds. Its structure was established
by X-ray diffraction analysis.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1604–1606, August, 1999. 相似文献
5.
S. I. Moryashova L. K. Salamandra A. E. Fedorov L. A. Rodinovskaya A. M. Shestopalov V. V. Semenov 《Russian Chemical Bulletin》1998,47(2):357-360
Reactions of sodium derivatives of 2- and 3-thenoylacetaldehydes with cyanothioacetamide gave 2- and 3-cyano-6-thienylpyridine-2(1H)-thiones, which were used in the synthesis of substituted 2-alkylthiopyridines, thieno[2,3-b]pyridines, and other fused heterocycles.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 365–368, February, 1998. 相似文献
6.
Summary 3(Bis(alkylthio)methylene)-3H-isobenzofuran-1-ones2a–e and 2-(bis(alkylthio)methylene)-3(2H)-benzofuranone derivatives4a–c are obtained by reaction of phthalides1a–d or 3(2H)-benzofuranone (coumaranone3), respectively, with carbon disulfide under basic conditions followed by alkylation. The reaction behaviour of the new compounds2 and4 is investigated. 2-((2-Dimethylthio-1-oxo)ethyl)benzoic acid N,N-dimethylamide (7a) and 2-((2-dimethylthio-1-oxo)ethyl)-benzoic acid 2-methylpiperidide (7b) are surprisingly formed instead of the methylthio substitution products by treatment of2a with the corresponding amine in the presence of aluminum chloride.
Herrn Professor Dr. Dr. h. c.Waldemar Adam zum 60. Geburtstag gewidmet 相似文献
7.
Li-juan Yang Xiao-dong Yang Shu Yang Jing-feng Zhao Hong-bin Zhang Liang Li 《Chemistry of Natural Compounds》2006,42(6):649-651
Two new benzoyl esters of glucose 1-O-(E)-4′-methoxybenzoyl-β-D-glucopyranose (1) and 1-O-(E)-4′-methoxybenzoyl-β-D-gluconic acid (2) were isolated from Lagotis yunnanensis, together with six previously known iridoid glucosides. The structures of these compounds were elucidated on the basis of
spectral analysis, including 2D NMR spectroscopy.
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 529–530, November–December, 2006. 相似文献
8.
A. R. Mustafina L. V. Ermolaeva S. N. Sudakova A. S. Mikhailov V. S. Reznik 《Russian Chemical Bulletin》1994,43(12):2026-2029
The acid-base properties of 4,6-dimethyl- and 4,6-diamino-2(1H)-pyrimidinethiones (1 and2) were investigated by potentiometric titration. Dissosiation of1 and protonation of its anion occur in two steps, the first of which affords the deprotonated dimer [HA2)–. The relative stability of the dimer depends on the nature of the solvent. The effect of kinetic factors on the acid-base behavior of1 was elucidated by comparing the results of potentiometric titrations carried out under various kinetic conditions. It was concluded that the difference between the acid-base properties of1 and2 results from the electron-donating effect of the amino groups.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2145–2148, December, 1994. 相似文献
9.
Knoevenagel condensation of acrolein with NCCH2COOK or NCCH2CONH2 in 1M aqueous solutions of K and Na phosphates gave 2-cyanopenta-(2E,4)-dienoic acid and its amide, respectively.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 363–365, February, 1998. 相似文献
10.
M. Madesclaire V. P. Zaitsev J. V. Zaitseva S. Kh. Sharipova 《Chemistry of Heterocyclic Compounds》2007,43(10):1325-1332
A synthesis is reported for (4R,5R)-and (4S,5S)-4-hydroxymethyl-5-(4-nitrophenyl)oxazolidin-2-ones and (1′R,4R)-and (1′S,4S)-4-[hydroxy(4-nitrophenyl)methyl]oxazolidin-2-ones from (1R,2R)-and (1S,2S)-2-amino-1-(4-nitrophenyl)-1,3-propanediols. The effect of the experimental conditions on the formation of these compounds
was studied.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1562–1570, October, 2007. 相似文献
11.
M. Chakrabarty A. Batabyal M. S. Morales-Ríos P. Joseph-Nathan 《Monatshefte für Chemie / Chemical Monthly》1995,126(6-7):789-794
Summary Unambiguous1H and13C NMR assignments for 4(3H)-quinazolinones1–6 and their corresponding 4-thiones7–12 have been made. This resulted in the revision of the previous assignments for the two benzenoid carbons (C-5 and C-8) of quinazolinones1,2,4, and5. Thionation of the nucleophilic amides1–6 has been found to cause a distinct change in the13C chemical shift of particularly C-4, but also of those of C-4a, C-5, and C-8a. One-bond and several long range heteronuclear coupling constants for the compounds have also been measured.
Kernresonanzspektroskopie von 4(3H)-Chinazolinonen und 4(3H)-Chinazolinthionen
Zusammenfassung Die1H- und13C-NMR-Spektren der 4(3H)-Chinazolinone1–6 und ihrer entsprechenden 4-Thione7–12 wurden zugeordnet. Dabei zeigte sich, daß eine frühere Zuordnung der beiden benzoiden Kohlenstoffe (C-5 und C-8) der Chinazolinone1,2,4 und5 falsch war. Ersatz des Sauerstoffs durch Schwefel in den nukleophilen Amiden1–6 führt insbesondere für C-4, aber auch für C-4a, C-5 und C-8a zu einer deutlichen Änderung der chemischen Verschiebung. Heteronukleare Kopplungskonstanten über eine und über mehrere Bindungen wurden bestimmt.相似文献
12.
D. L. Lipilin A. Yu. Tyurin O. Yu. Smirnov A. M. Churakov Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》2006,55(7):1239-1242
Treatment of 2-(tert-butyl)-1,2,3,4-benzotetrazinium tetrafluoroborates with sodium thiocyanate afforded 2-(tert-butylazo)phenyl isothiocyanates 3, which exist in equilibrium with 2-(tert-butyl)-1,2,4-benzotriazine-3(2H)-thiones 3′. The equilibrium depends on the substituents R in the benzene ring: the percentage of the open isomer 3 is about 20% for R = H or Me; for R = Cl or Br, the equilibrium is completely shifted to cyclic isomer 3′. The equilibrium is slow on the time scale of the 1H and 13C NMR experiments. For compounds 3a/3′a (R = H), the spectra at 24 °C show two sets of signals, while those at 0 °C contain only signals for isomer 3′a.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1192–1195, July, 2006. 相似文献
13.
A. F. Shidlovskii A. S. Peregudov B. B. Averkiev M. Yu. Antipin N. D. Chkanikov 《Russian Chemical Bulletin》2004,53(9):2060-2070
The reactions of 2-chloro-1-cyano-1-diethoxyphosphoryl-2-trifluoromethylethylene (2a) and 2-chloro-2-chlorodifluoromethyl-1-cyano-1-diethoxyphosphorylethylene (2b) with arylamines, arylhydrazines, amidines, 2-aminopyridines, and 5-aminopyrazoles were studied. Alkenes 2a, b can serve as precursors of aminopyrazoles, pyrimidines, pyrido[1,2-a]pyrimidines, and pyrazolo[1,5-a]pyrimidines modified with the fluoroalkyl and diethoxyphosphoryl groups. Intermediates of some heterocyclization reactions were detected by NMR spectroscopy. The structures of the compounds were confirmed by X ray diffraction analysis.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1977–1986, September, 2004. 相似文献
14.
《合成通讯》2013,43(18):3233-3241
Abstract A concise synthesis of (2E,4Z)-2,4-heptadien-1-ol and (2E,4Z)-2,4-heptadienal is presented. Commercially available (Z)-2-penten-1-ol was converted to ethyl-(2E,4Z)-2,4-heptadienoate by reaction with activated MnO2 and (carboethoxymethylene)triphenylphosphorane in the presence of benzoic acid as a catalyst. Ethyl-(2E,4Z)-2,4-heptadienoate was converted to (2E,4Z)-2,4-heptadien-1-ol with LiAlH4. The alcohol was partially oxidized to (2E,4Z)-2,4-heptadienal with MnO2. The title compounds are male-specific, antennally active volatile compounds from the Saltcedar leaf beetle, Diorhabda elongata Brulle (Coleoptera: Chrysomelidae) and have potential use in the biological control of the invasive weed saltcedar (Tamarix spp). 相似文献
15.
A general method for the preparation of unsymmetricaltrans-2-allyl-6-alkyl(aryl)-1,2,3,6-tetrahydropyridines6 based on a combination of 1,2-addition of RLi to pyridine andtrans-6-allylation with triallylborane in the presence of methanol was elaborated. It was shown thattrans-piperideines (6 (R=Alk, Ph) isomerize into the correspondingcis-2-allyl-6-alkyl(phenyl)-3-piperideines14 on heating with triallylborane followed by deboronation of aminoborane (16) with methanol and an alkali. The stereochemistry of compounds6 and14 was determined by two-dimensional NOE spectroscopy. A possible mechanism of the formation oftrans-amines6 and their transformation intocis-isomers14 is discussed. Alkaloids (±)-epidihydropinidine (trans-2-methyl-6-propylpiperidine2a, 70%) and (±)-dihydropinidine (cis-2-methyl-6-propylpiperidine1d, 71%) were synthesized by hydrogenation of compound6a (R=Me) and14a (R=Me), respectively, over Raney nickel.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 467–474, March, 1998. 相似文献
16.
Hans Junek Georg Uray Anna Kotzent Gabriele Kastner 《Monatshefte für Chemie / Chemical Monthly》1985,116(10):1199-1208
Ether cleavage of the two isomeric diamino-methoxy-pyridine-carbonitriles1 and2 leads to the isomeric 4,6-diamino-2(1H)-pyridone-3-carbonitrile (3 a) and 2,4-diamino-6(1H)-pyridone-3-carbonitrile (4 a), resp. Dependent on the reaction conditions in glacial acetic acid containing hydrogen bromide or potassium iodide the halogenated pyridones (3 b, 4 b–c) can be obtained.pK
s
-values and UV-spectra of the pyridones are discussed.3 a and4 a can be used as azo-coupling components, yielding the azo-dyes5 and6. Similarly 4-amino-6-hydroxy-2(1H)-pyridones (7 a–b) are coupled with several aryl- and heteroaryl-diazoniumsalts to form the azo-dyes8 a–g.
Herrn emer. o. Univ.-Prof. Dr.Otto Hromatka zum 80. Geburtstag gewidemet. 相似文献
17.
Shubhangi C. Joshi Kunjbihari N. Trivedi 《Monatshefte für Chemie / Chemical Monthly》1992,123(6-7):557-564
Summary The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (3 a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7 a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 b) afforded4 b and7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (13).3 a,4 b, and13 were further cyclized in acidic medium to9 a,10 b, and14 followed by dehydrogenation.This paper is dedicated to Dr. F. M. Dean, Department of Organic Chemistry, Robert Robinson Laboratories, University of Liverpool, Liverpool, U. K., on his retirement 相似文献
18.
L. M. Korotayeva T. Ya. Rubinskaya E. V. Klimkina V. P. Gultyai Yu. N. Bubnov 《Russian Chemical Bulletin》1999,48(4):754-757
Electrocatalytic hydrogenation oftrans-2-allyl-6-phenyl-1,2,3,6-tetrahydropyridine andtrans-2-allyl-6-methyl-1,2,3,6-tetrahydropyridine in 40% aqueous DMF in the presence of AcOH on a nickel cathode gavetrans-6-phenyl-2-propylpiperidine andtrans-2-methyl-6-propylpiperidine ((±)-epidihydropinidine), respectively. Direct electroreduction oftrans-2-allyl-6-phenyl-1,2,3,6-tetrahydropyridine in anhydrous DMF on a mercury cathode afforded a 7 ∶ 5 mixture oftrans- andcis-2-allyl-6-phenylpiperidine. The structure of the latter compound was confirmed by 2D NOESY spectroscopy. The possible mechanism
of formation of thecis-isomer is discussed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No.4, pp. 758–761, April, 1999. 相似文献
19.
The reactions of 1-substituted 2-nitro-3-phenylaminoprop-2-en-1-ones with cyanothioacetamide afforded the corresponding 6-substituted 3-cyano-5-nitropyridine-2(1H)-thiones, which were used for the synthesis of 6-substituted 3-cyano-2-methylthio-5-nitropyridines and 7-substituted 4-hydroxy-8-nitropyrido[2",3":4,5]thieno[2,3-b]pyridin-2(1H)-ones. 相似文献
20.
Ning Ma Wen-Ying Liu Huan-De Li Xin-Yu Jiang Bi-Kui Zhang Rong-Hua Zhu Feng Wang Wei Liu Xia Liu Da-Xiong Xiang 《Chromatographia》2007,66(3-4):251-255
(E)-3,5,4′-trimethoxystilbene (BTM-0512) is a resveratrol analog with a variety of pharmacological action, including anti-cancer
properties, anti-allergic activity, estrogenic activity, antiangiogenic activity, and vascular-targeting activity against
microtubule-destabilization. There is, however, no validated analytical method for quantification of (E)-3,5,4′-trimethoxystilbene in biological matrices, so pharmacokinetic data and suitable methods for determination of the
compound in plasma are currently lacking. A rapid and sensitive liquid chromatographic–mass spectrometric method for determination
of (E)-3,5,4′-trimethoxystilbene in rat plasma, using carbamazepine as internal standard, has been developed and validated. Plasma
samples were treated with acetonitrile to precipitate proteins. Samples were then analyzed by HPLC on a 250mm × 4.6 mm i.d.,
5-μm particle, C18 column with methanol–water, 80:20 (v/v), containing 10 mm ammonium acetate and 0.2% formic acid (pH 3.0), as mobile phase, delivered at 0.85 mL min−1. A single-quadrupole mass spectrometer with an electrospray interface operated in selected-ion monitoring mode was used to
detect [M + H]+ ions at m/z 271.3 for (E)-3,5,4′-trimethoxystilbene and m/z 237.5 for the internal standard. (E)-3,5,4′-trimethoxystilbene and the internal standard eluted as sharp, symmetrical peaks with retention times of 8.9 and 4 min,
respectively. Calibration plots for (E)-3,5,4′-trimethoxystilbene in rat plasma at concentrations ranging from 0.01 to 5.0 μg mL−1 were highly linear. Intra-day and inter-day precision, as RSD, was <12.9%, and accuracy was in the range 94.8–104.7%. The
limit of detection in plasma was 0.005 μg mL−1. The method was successfully used to determine the concentration of (E)-3,5,4′-trimethoxystilbene after oral administration of 86 mg kg−1 of the drug to Sprague–Dawley rats and can be used to investigate the pharmacokinetics of the compound. 相似文献