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1.
2,2,4-Trichloro-6-phenyl-4,5-dipyrimidinyl, for which nucleophilic substitution with piperdine under various conditions was studied, was obtained from 2,2,4-trioxo-6-phenyl-1, 1,2,2,3,4-hexahydro-4,5-dipyrimidinyl. It is shown that there is an appreciable difference in the rates of substitution of the first, second, and third chlorine atoms, and this made it possible to obtain reaction products that contain one, two, and three piperidino groups. The chlorine atom in the 4 position is replaced initially, after which the chlorine atom in the 2 position undergoes substitution. The structures of the compounds were proved by chemical transformations and analysis of the PMR spectra.See [1] for communication 69.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 821–826, June, 1979.  相似文献   

2.
Ethyl benzoate thiocarbohydrazone, which exists in solution with a cis-to-trans isomer ratio of 4.51, was obtained by reaction of ethyl imidobenzoate hydrochloride with thiocarbohydrazide. In polar solvents the product readily splits out a molecule of alcohol to give 3-phenyl-4-amino-1, 2,4-triazoline-5-thione and on oxidation with hydrogen peroxide in glacial acetic acid it is converted to 6,6-diphenyl-3,3-biz(sym-tetrazinyl) disulfide, which can be reduced to 6-phenyl-1,2-dihydro-sym-tetrazine-3-thione.See [1] for communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1564–1568, November, 1977.  相似文献   

3.
The specific intramolecular interaction between the -proton of the vinyl group and the pyridine nitrogen atom of the second imidazole ring, similar to the hydrogen bond, is accomplished in 1-vinyl- and 1,1-divinyl-2,2-biimidazolyls. In 1-vinyl-2,2'-biimidazolyl, the available NH-proton of the 2'-imidazole ring is localized at the nitrogen atom in the anti orientation in relation to the vinyl group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2747–2750, December, 1990.  相似文献   

4.
The IR spectra of methyl, chloro, and phenyl derivatives of 3-hydroxypyridines in CCl4 solutions and in the crystalline state were studied. A comparison of the frequencies, half widths, and integral intensities of the bands of the stretching vibrations of the hydroxyl groups in the spectra of solutions of the 3-hydroxypyridine derivatives in CCl4 with the characteristic OH bands in the spectra of phenols demonstrates that 3-hydroxypyridines exist practically completely in the hydroxy form in dilute CCl4 solutions. The shift in the OH bands in the spectra of 2-phenyl-3-hydroxypyridine derivatives indicates that the OH group forms a -hydrogen bond with the phenyl ring. The presence also of a band of a free OH group is evidence for the existence of s-cis and s-trans conformers relative to the C-O bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 187–190, February, 1972.  相似文献   

5.
A new method of preparing 1, 2, 4-triazolinethione derivatives by directly sulfurating the corresponding triazoles is described. 4-(-Pyridyl)-1, 2, 4-triazoline-3-thione undergoes aminomethylation, cyanoethylation, and pyridylethylation at the nitrogen of the thioamide group. Replacement of the phenyl group in 4-phenyl-1, 2, 4-triazolinethione by -pyridyl, gives a compound closely resembling 1-phenyltetrazoline-5-thione in its properties.For Part VII see [1].  相似文献   

6.
Summary It was shown that In contrast to the Meerwein-Koelsch reaction, the decomposition of benzenediazonlum fluoborate In esters of ,-unsaturated acids proceeds by a heterolytlc mechanism with the phenyl attacking the -carbon and the carbalkoxyl group of these esters. The reaction with ethyl crotonate gave -methylatropic acid (after hydrolysis) and a small amount of a dibasic acid, C14H16O4 (or C14H14O4). With methyl acrylate it gave atropic acid, phenyl acrylate, and a smaller amount of -methyl--phenylglutaric acid. With methyl methacrylate It formed benzylacrylic acid and the product of further conversions of phenyl methacrylate, namely the keto phenol 2-methyl-5-hydroxyindan-1-one.  相似文献   

7.
Conclusions As a rule, the equilibrium of the skewed twist conformera is observed for the 3(4)-halogen-substituted caran-4(3)-ols and 3-methylnorcaran-4(3)-ols. This is indicated by the simultaneous presence of the bands of OH of the free OH groups and the OH groups bound by intramolecular hydrogen bonds. The steric interactions of the 7-R groups with the cis substituents at C3 and C4 and the intramolecular hydrogen bonds OH... Hal and OH... cyclopropane ring play a role in the realization of one or the other form. In the case of uniform substitution, the influence of the halogens on OH changes in the series F相似文献   

8.
The effect of a nitrogen atom in various positions of the heteroaromatic ring on the ketol-enol equilibrium of 2-, 3-, and 4-pyridoyl-, 2- and 4-pyrimidoyl-, pyrazinoyl-, and 3- and 4-pyrazinoylacetic esters is examined. The anomalous effect of a nitrogen atom on the position relative to the tautomeric fragment is noted and is explained by interaction of the unshared pair of the nitrogen atom with the orbitals of the carbonyl group, which may lead to a decrease in the acceptor character of the azine substituent.See [1] for Communication 4. In Communication 4 [Khim. Geterotsikl. Soedin., No. 6, p. 823 (1980)] there is a misprint in the scheme that illustrates the tautomeric equilibrium -keto esters with the participation of protonated forms. See [16] for the corrected scheme.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 530–535, April, 1981.  相似文献   

9.
Boiling 2-methyl-4-oxo-3,4-dihydrothionaphtheno[3,2-d]-pyrimidine with phosphorus oxychloride gives 2-methyl-4-chlorothionaphtheno [3,2-d]pyrimidine (II), in which the chlorine atom is mobile. Nucleophilic substitution of the mobile chlorine atom in compound II gives the 4-ethoxy,4-(N-piperidino),4-(N4-methyl-N-piperazino), 4-[2-(diethylamino)ethylamino],4-3-(diethylamino)-2-hydroxypropylamino]substituted derivatives.  相似文献   

10.
Summary Complexes of adenosine-5-triphosphate, adenosine-5-monophosphate, guanosine-5-monophosphate, inosine-5-monophosphate, cytidine-5-monophosphate and uridine-5-monophosphate with vanadyl ion, have been studied in the solid state by i.r. spectroscopy and magnetochemically. All complexes have normal magnetic moments, very close to the spin-only values. From the i.r. spectra it is suggested that the vanadyl ion is interacting with adenosine-5-triphosphate, through the N-1 of the purine ring, with adenosine-5-monophosphate, guanosine-5-monophosphate, inosine-5-monophosphate, through the N-7 of the purine ring, with cytidine-5-monophosphate through the N-3 of the pyrimidine ring, and most probably through the phosphate group with uridine-5-monophosphate. The complexes of vanadyl ion with the nucleotides are probably polymeric.  相似文献   

11.
The conformational equilibrium in solution was examined by NMR spectroscopy for a series of 7-phenyl-3-borabicyclo[3.3.1]nonane derivatives containing various substituents at the boron atom. The structures of these derivatives were studied in the crystalline state (X-ray diffraction analysis) and by quantum-chemical calculations (B3Pw91/6-31G*). The B...Ph transannular interactions corresponding to charge transfer from the system of the phenyl group to the vacant p-orbital of the B atom were demonstrated to be responsible for unique stability of the chair-chair conformation of these derivatives.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1884–1896, September, 2004.  相似文献   

12.
TG and DTA of the compounds Mn(phen)2X2 (where X=CN,CNO, NCS and NCSe), Mn(phen) (NCS)2, Mn(NCS)2 and Mn(NCSe)2 (wherephen=1,10 phenanthroline) are reported and discussed. Decomposition schemes are proposed based on TG and DTA results and, where possible, the analysis and properties of intermediates formed during thermal breakdown. The decomposition of thiocyanate and selenocyanate ligands is observed to lead to an apparent slight increase in sample weight. This phenomenon is discussed in relation to buoyancy changes resulting from the release of sulphur or selenium vapours.
Zusammenfassung TG und DTA Untersuchungen der Verbindungen Mn(phen)2X2 (X=CN, CNO, NCS und NCSe), Mn(phen) (NCS)2, Mn(NCS)2 und Mn(NCSe)2 (phen =1.10 Phenantrolin) werden beschrieben. Anhand der TG- und DTA-Ergebnisse werden Zerzetzungsschemata vorgeschlagen und wenn möglich, Analyse und Eigenschaften der im Laufe der thermischen Zersetzung entstandenen Zwischenprodukte angegeben. Es wurde beobachtet, da\ die Zersetzung der Thiocyanat- und Selenocyanatliganden zu einer scheinbaren schwachen Zunahme des Probengewichts führt. Dieses PhÄnomen wird im Zusammenhang mit infolge der Abspaltung von Schwefel- oder SelendÄmpfen auftretenden Änderungen des Auftriebs diskutiert.

Résumé On décrit et discute la TG et l'ATD des composés Mn(phén)2X2 (X=CN, CNO, NCS et NCSe), Mn(phén) (NCS)2, Mn(NCS)2 et Mn(NCSe)2 (oùphén=1,10 phénantroline). On propose des schémas de décomposition à partir des résultats de TG et d'ATD et, si possible, on donne l'analyse et les propriétés des produits intermédiaires formés lors de la décomposition thermique. On a observé que la décomposition des ligands de thiocyanate et de sélénocyanate entraine une faible augmentation apparante du poids du prélèvement. On explique ce phénomène par les variations de poussée résultant du dégagement de vapeurs de soufre ou de sélénium.

()22, () (NCS)2, Mn(NCS)2 Mn(NCSe)2, X=CN, CNO, NCS, NCSe =1.10. , , - , . . - , .


We wish to express our thanks to Professor S. C. Bevan for helpful advice, particularly in connection with the buoyancy effect noted for thiocyanate and selenocyanate complexes.  相似文献   

13.
The new flavanon lehmannin (I) has been isolated from the roots ofAmmothamnus lehmannii Bunge. On the basis of chemical transformations and with the aid of physicochemical characteristics it has been established that compound (I) has the structure of 2,4,7-trihydroxy-8-(2-isopropenyl-5-methylhex-4-enyl)flavanone. The alkaline cleavage of lehmannin gave ammothamnidin (V). The structure proposed previously for the chalcone ammothamnidin has been corrected. It has been shown that it has the structure of 2,2-4,4-tetrahydroxy-3-(2-isopropenyl-5-methylhex-4- enyl)chalcone. A comparative study of the13C NMR spectra of a number of flavanones has revealed an empirical law permitting the prediction of the presence or absence of substituents (OH and OCH3) at C-2 from the value of the chemical shift of the signal of the C-2 carbon atom.Institute of the Chemistry of Plant Substances of the Uzbek SSR Academy of Sciences, Tashkent. I. P. Pavlov Samarkand State Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 516–524, July–August, 1987.  相似文献   

14.
Pyrimidines     
The reaction of substituted 3-methyl-5-pyrazolones with arylidenebisureas has been studied. Substituted spiro[pyrazole-4, 5-pyrimidines] have been obtained from 1-phenyl- and 1-benzyl-3-methyl-5-pyrazolones. When only one hydrogen atom was present in the ring of the 3-methyl-5-pyrazolone, the corresponding -ureidobenzyl derivative was obtained.For communication XI see [1].  相似文献   

15.
Diffuse-reflectance IR spectroscopy is used to study the interaction of C3 and C6 alkanes (propane, n-hexane, 3-methylpentane, and cyclohexane) with the Brønsted acid sites of hydrogen-exchanged mordenite, ferrierite, ZSM-5, and faujasite. It is found that a shift of the absorption band of the stretching vibrations of acidic Si(OH)Al groups toward lower frequencies (OH) due to the formation of a hydrogen bond with adsorbed alkanes increases in the following series: OH(propane) < OH(n-hexane) = OH(3-methylpentane). The accessibility of Si(OH)Al groups to alkane molecules is determined by the dimension of rings through which molecules enter zeolite channels and cavities. It follows from the measured OH values that the strength of Brønsted acid sites decreases in the following series: HZSM-5 > H-mordenite H-ferrierite HY. The difference between the three high-silica zeolites is not great. The results obtained are compared with the published IR data on Si(OH)Al groups of zeolites with adsorbed alkanes and other weak bases.  相似文献   

16.
Kinetics of oxidation of propylene to propylene glycol and its acetates in acetic acid solutions of lithium nitrate over Pd/C and Pd–Pt/C catalysts has been studied. Catalysts were investigated using X-ray phase analysis and electron microscopy. Platinum introduction into catalyst increases the metal dispersity and the catalyst stability but produces no effect on the nature of surface sites active in propylene oxidation.
Pd/C Pd–Pt/C. . , , , .
  相似文献   

17.
The reaction of substituted methyl 1-adamantyl ketones with an equimolar amount of 5-phenyl-2,3-dihydrofuran-2,3-dione under the conditions of the thermal decarbonylation of the latter leads to the corresponding 2-methyl-2-adamantyl-6-pheny1-1,3-dioxen-4-ones, 6-phenyl-3-benzoyl-2,4-dione, and the starting ketones. The steric and electronic factors that affect the yields of the dioxen-4-ones were examined. -Hydroxymethyl 1-adamantyl ketones open up the furan ring to give 1-adamantoylmethyl benzoylpyruvate. Data from the IR, PMR, and UV spectra are presented.See [1] for communication 27.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1312–1315, October, 1982.  相似文献   

18.
Conclusions Cyclometallation of 1-(3,4-dimethoxyphenyl)-2-methyl-3-(4-nitrophenyl)-2-azapropane upon treatment with Pd(II) acetate occurs at the electron rich dimethoxy-substituted aromatic ring in CHCl3 solution, and at the electron poor nitrophenyl ring in AcOH solution.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 175–181, January, 1988.  相似文献   

19.
The dependence of the chemical shifts of the ring protons on the pH of the medium for a number of 4-hydroxyquinoline derivatives was studied by means of PMR spectroscopy. The dipolar and uncharged hydroxy forms exist in equilibrium in aqueous solutions. The effect of intramolecular hydrogen bonding on the character of the dependence of the chemical shift on the pH of the medium in the case of 3-piperidinomethyl-4-hydroxyisoquinoline was investigated. The possibility of the separate protonation of the ring nitrogen and the side-chain nitrogen in 3-piperidinomethyl-4-hydroxyisoquinoline was established. The distribution of the -electron density in 4-hydroxyisoquinoline is in good agreement with its chemical behavior.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1546–1549, November, 1971  相似文献   

20.
A study is made of new synthetic routes, based on accessible 3-formyl-7-azaindoles, to 3-substituted 7-azaindole. 2-Phenyl-4-(1-phenyl-4-methyl-7-azaindolyl-3-rnethylene)-1, 3-oxazol-5-one is synthesized, and it is converted to 1-phenyl-4-methyl-7-azatryptophane, 1-phenyl-4-methyl-7-azaindolyl-3-acetic acid,1-phenyl-3-(,-dihydroxypropyl)-4-methyl-7-azaindole, and 1-phenyl-4-methyl-7-azaindolyl-3-pyrotartaric acid.For Part XVIII see [1].  相似文献   

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