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1.
The crystal structures of dimethyl 2,2,4,4-tetramethyl-3-oxocyclobutane-1-spiro-5-3,4-diphenyl-(1,3)-thiazolidine-2,2-dicarboxylate, C26H29NO5S for V, and dimethyl 3,4-diphenyl-5-isopropylidene-(1,3)-thiazolidine-2,2-dicarboxylate, C22H23NO4S for VI, have been solved. The 1,3-thiazolidine ring of compound V has got twisted conformation, while in compound VI this ring adopts envelope. In both structures short inter- and intramolecular contacts were found, which can be recognized as hydrogen bonds.  相似文献   

2.
Co-receptor 1,3-calix[4]-di(aza-benzo)crown-crown-6 (1-H) designed with one calix[4]arene in a 1,3-alternate conformation and hard and soft metal ion binding sites has been prepared according to three pathways (A-C). Pathway B, consisting of two different 1 + 1 condensations with ditosylate derivatives, was shown to be the most efficient.  相似文献   

3.
Summary 3-Aroyl-4-aryl-2-pyrazolines (21–40) have been synthesized by the reaction of ,-unsaturated ketones (1–20) with diazomethane. These 2-pyrazolines gave -methyl-,-unsaturated ketones (41–46) on thermal denitrogenation.Dedicated to Prof. Dr.F. Sauter on the occasion of his 65th birthday  相似文献   

4.
1-(2-hydroxybenzoyl)piperidine, C12H15NO2, orthorhombic, Pbc21-C 2v 5 ;a=9.529 (1),b=10.001 (1),c=11.652 (1) Å;Z=4. The structure was determined from 1 510 single crystal X-ray data by direct methods and the refinement of the structure parameters yieldedR=0.040. There is one molecule in the asymmetric unit.4-(2-hydroxybenzoyl)morpholine, C11H13NO3, orthorhombic, P212121-D 2 4 ;a=13.006 (1),b=17.258 (2),c=9.125 (1) Å;Z=8. The structure parameters of the isotypic compound 4-(2-hydroxythiobenzoyl)morpholine were used in a starting set of refinement; finallyR=0.054 was obtained for 1 900 single crystal X-ray data. There are two molecules in the asymmetric unit.In both compounds the hydrogen atoms could be located by means of differenceFourier summations. The intermolecular hydrogen bonds with O ... O distances of 2.649 (2) Å for the piperidine derivate and 2.688 (3) resp. 2.754 (3) Å for the morpholine derivate are typical for intermediate bond strengths.
Die Strukturen von 1-(2-hydroxybenzoyl)piperidin und 4-(2-hydroxybenzoyl)morpholin
Zusammenfassung 1-(2-hydroxybenzoyl)piperidin, C12H15NO2, orthorhombisch, Pbc21-C 2v 5 ;a=9.529 (1),b=10.001 (1),c=11.652 (1) Å;Z=4. Die Struktur wurde aus 1 510 Einkristallröntgendaten mittels direkter Methoden bestimmt; die Strukturverfeinerung ergabR=0.040. Es ist ein Molekül in der asymmetrischen Einheit.4-(2-hydroxybenzoyl)morpholin, C11H13NO3, orthorhombisch, P212121-D 2 4 ;a=13.006 (1),b=17.258 (2),c=9.125 (1) Å;Z=8. Die Strukturparameter der isotypen Verbindung 4-(2-hydroxythiobenzoyl)morpholin wurden als Startsatz für die Strukturverfeinerung benutzt. Es wurdeR=0.054 aus 1 900 Einkristallröntgendaten erreicht. Es befinden sich zwei Moleküle in der asymmetrischen Einheit.In beiden Verbindungen konnten mittels Differenz-Fourier-Summierungen die Wasserstoffatome lokalisiert werden. Die intermolekularen Wasserstoffbrükken mit O ... O-Distanzen von 2.649 (2) Å für das Piperidinderivat und 2.688 (3) bzw. 2.754 (3) Å für das Morpholinderivat sind typisch für mittlere Bindungsstärken.
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5.
Four phenolic components are isolated from the CHCl 3 extract ofEmpetrum nigrumL. Three of them are known from this plant. The fourth (6,8-dimethylpinocembrine) is isolated from crowberry for the first time. The previously proposed structure for 2'-methoxy-4'-hydroxy- ,-dihydrochalcone is confirmed by x-ray structure analysis  相似文献   

6.
Several halomethyl-arylcarbinols were prepared, and the influence of substituents on enantiomer selectivity in the acetalisation reaction with [2S-(2,3a,4,7,7a)]-octahydro-7,8,8-trimethyl-4,7-methanobenzofuran-2-ol was examined.
Unserem sehr verehrten Lehrer, Herrn Prof. Dr.Otto Hromatka, mit den besten Wünschen zum 80. Geburtstag gewidmet.  相似文献   

7.
Reaction of 2-methyl-4,5-dihydrofuran with HCl at 0°C yields 5-chloro-2-pentanone (13%) and 1-(2-methyltetrahydrofuryl-2)-5-chloro-2-pentanone (27%) and at 200° 5-chloro-2-pentanone exclusively.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. I. M. Gubkin State Petroleum and Gas Academy, 117917 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2188–2191, September, 1992.  相似文献   

8.
The 1-[1,8-bis(dimethylamino)-4-naphthyl[ethyl carbocation generated from the corresponding alcohol in benzene in the presence of Al2O3 undergoes elimination according to theE1 mechanism to give previously unknown 1,8-bis(dimethylami no)-4-vinyl naphthalene in a good yield. This compound was also synthesized from 1,8-bis(dimethylamino)-4-formylnaphthalene by the Wittig reaction. Polymerization of the vinylic derivative obtained was studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2297–2300, September, 1996.  相似文献   

9.
An X-ray structural investigation (1274 reflections,R=0.057) has established that 2-(ptolyl)amino-5, 6-benzo-2H-chromene exists in the crystalline state as a cyclic 2H-chromene tautomer. This molecule is nonplanar due to the tetrahedral coordination of the C(1) atom and the relative rotation of phenyl and benzochromene rings.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 515–517, March, 1993.  相似文献   

10.
The intercalation of ferrocene and dimethylaminomethylferrocene into -tin(IV) hydrogen phosphate (SnP) and -vanadyl phosphate has been investigated. Successful intercalation of 0.81 mol of dimethylamino-methylferrocene into -SnP by an acid-base reaction in aqueous medium to form a bilayer of protonated amines was achieved. However, ferrocene was not intercalated under the same conditions. Intercalation of -vanadyl phosphate by 0.11 mol of ferrocene in acetonic medium at room temperature was effected by a redox topotactic reaction. The voluminous dimethylaminomethylferrocene was not intercalated into -vanadyl phosphate.  相似文献   

11.
12.
The two hydroxyls of yuccagenin can be glycosylated by Koenigs-Knorr condensation with acetobromorhammose in dichloroethane in the presence of mercuric cyanide. The bisrhamnoside of yuccagenin markedly lowers the cholesterol and triglyceride content in blood serum of healthy animals and animals with experimental hyperlipidemia.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 242–243, May–June, 2000.  相似文献   

13.
The 15- and 17-hydroxy derivatives of 8-aza-D-homogona-12,17a-diones were obtained by the annelation of 3,4-dihydroisoquinolines with 2-acetyl-4-hydroxycyclohexane-1,3-dione. It was shown that the reaction proceeds stereoselectively with the intermediate formation of 9,15- and 9,17-trans isomers. The probable mechanism and certain aspects of the interconnection between the structural and physicochemical characteristics of the obtained compounds are discussed.  相似文献   

14.
The polarographic behaviour of 3-(2-thiazolylazo)-2,6-diaminopyridine (2,6-TADAP) has been studied in aqueous buffer solutions and aqueous-ethanol mixtures of different pH's using DC and DP polarographic methods. The reduction of the azo linkage takes place via two electrons in both aqueous and aqueous-ethanol mixtures. The linear relationship between the current and 2,6-TADAP concentration allowed the polarographic determination of 2,6-TADAP over a wide concentration range. The values of the adsorption parameters in the presence of both Triton X-100 (non-ionic) and a new non-ionic surfactant, nonylphenol polyoxypropylene polyoxyethylene (NPE 1800) have been computed. The kinetic parameters of the electrode reaction have been calculated.On leave from An-Najah National University, Nablus, West Bank, Via Israel.  相似文献   

15.
The preparation of 4-(-chloroalkyl)pyridazines (4, 7b, 7c, 10) is reported. Compounds4, 7a, 7b, and7c were found to be attacked by methoxide ions mainly at the heteroaromatic ring, thus forming 5-methoxy-4-alkylpyridazines.10 on reaction with sodium methanolate yields exclusively 4-benzyl-5-methoxymethyl-pyridazine (12). In addition, starting from4, the amines5a, 5b, 6a, and6b were prepared.
Herrn Univ.-Prof. Dr.Karl Schlögl mit den herzlichsten Wünschen zum 60. Geburtstag gewidmet.  相似文献   

16.
A new compound from the series of alkoxyketoiminates, Cu(II) bis-(2-methoxy-2,6-dimethyl-3-imino-5-heptanonate), has been synthesized and studied by X-ray crystallography. Crystal data for CuO4N2C20H36: a=10.154(1), b=9.921(1), c=11.684(2) , =96.17(1)°, space group P21/c, Z=2, dcalc =1.226 g/cm3, R=0.037. The structure is molecular and built from isolated trans-complexes. The copper atom has a plane square environment of two oxygen atoms (Cu–O 1.93 ) and two nitrogen atoms (Cu–N 1.90 ). The O–Cu–N chelate angle is 91.7°. The complex has an intramolecular hydrogen bond, N–H...O 2.16 , involving the alkoxy oxygen atom. The molecular packing in the crystal is close to that of copper(II) dipivaloylmethanate. The calculated van der Waals intermolecular interaction energies and thermogravimetric characteristics of the complexes are compared.  相似文献   

17.
The oxidative decarboxylation sequence (1a 2a 3a 4a 5a) affording -aminobutanoic acid (5a) is adapted to the synthesis of its hydroxy derivative5b. A facile high yield conversion of (2S, 4R)-4-hydroxyproline-methylester-hydrochloride (7) to (R)-GABOB (5b) on a preparative scale is reported with the hydroxypyrrolidone8 as the intermediate.
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18.
The X method has been utilized to calculate the electronic structure of trans-TiCl2(H2O) 4 + and trans VCl2(H2O) 4 + ions. Different conformations of coordinated water molecules have been considered. It has been found that the most stable configuration in both cases is the one with the plane of the water molecules parallel to the Cl-metal-Cl axis. The nature of the tetragonally distorted ground state has been found to depend on the orientation of the water molecules in these systems.  相似文献   

19.
Summary Several Mn, Cu, and Zn chelates of etiobiliverdin-IV-, mesobiliverdin-IX, and its dimethyl ester are studied. The results show that the chemical constitution of the Cu biliverdin chelate corresponds to a formal metal oxidation state of (II) coordinated to a neutral radical of the NH trideprotonated biliverdin. The reactivity of the Cu(II) bilindione chelates in nucleophilic solvents agrees with that expected for a neutral radical structure of the ligand; in CH3OH, they undergo oxidation towards dimethoxybilipurpurins. The magnetic behaviour of Cu(II) etiobiliverdinate-IV- in the solid state shows an intramolecular weak antiferromagnetic coupling d9Cu-to--radical (J=–23 cm–1) and an intermolecular weak antiferromagnetic coupling -radical-to--radical (J=–45 cm–1). The analogy of this magnetic behaviour to that of the cation radical of metalloporphyrins is discussed.
Reaktivität von Pyrrolpigmenten, 21. Mitt.: Struktur und Reaktivität von Cu(II)- und Zn(II)-Chelaten von Bilindionen
Zusammenfassung Einige Mn, Cu and Zn Chelate von Etiobiliverdin-IV-, Mesobiliverdin-IX und seinem Dimethylester werden untersucht. Im Komplex koordiniert ein Metallatom (mit der Formalladung II) mit einem Neutralradikal des dreifach NH-deprotonierten Bilindions. Die Reaktivität des Komplexes gegenüber nukleophilen Lösungmitteln entspricht erwartungsgemäß dem eines neutralen -Radikals; in CH3OH wird er zu Dimethoxybilipurpurin oxidiert. Bei Cu(II)-Etiobiliverdinat-IV beobachtet man im festen Zustand neben schwacher, antiferromagnetischer Kupplung zwischen d9Cu und -Radikal (J=–23 cm–1) auch eine schwache, intermolekulare, antiferromagnetische Wechselwirkung zwischen zwei -Radikalen (J=–45 cm–1). Dieses magnetische Verhalten wird dem des -Kationradikals von Metalloporphyrinen gegenübergestellt.
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20.
Synthesis of the 7,8-dicoumarinyl ethers: 7-methoxy-7,8-oxydicoumarin and 6,7-dimethoxy-7,8-oxydicoumarin, established that the structures of fatagarine and oreojasmine for which these two structures have been proposed, have to be revised. Synthesis of 7-methoxy-5,7-oxydicoumarin and 8-methoxy-7,7-oxydicoumarin exclude the possibility of these dicoumarinyl ether structures for fatagarine.
Naturstoffchemie. 121. Mitt.: Synthese von Dicumarinylethern mit den für das Fatagarin und das Oreojasmin vorgeschlagenen Strukturen
Zusammenfassung Durch die Synthese der 7,8-Dicumarinylether: 7-Methoxy-7,8-oxydicumarin und 6,7-Dimethoxy-7,8-oxydicumarin, ließ sich nachweisen, daß die für das Fatagarin und Oreojasmin vorgeschlagenen Strukturen revidiert werden müssen. Die Darstellung des 8-Methoxy-7,7-oxydicoumarin und 7-Methoxy-5,7-oxydicumarin schließen die Möglichkeit dieser Strukturen für das Fatagarin aus.
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