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1.
New tricylic heterocyclic systems and their methyl derivatives are synthesized. They are 2-methylimidazo[5, 4-e]benzo-1, 2, 3-thiadiazole, 2-methylimidazo[5, 4-g]benzo-1, 2', 3-thiadiazole, 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole, and 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole. Quaternary salts of the 1, 2-dimethyl derivatives are used to prepare symmetrical and unsymmetrical trimethinecyanines and dimethinemerocyanines containing rhodanine groups. The absorption maxima of the dyes are displaced towards the long wavelength region compared with imidacarbocyanines. It is shown that when 1, 2-dimetnyl-5-aminobenzoimidazole is thiocyanated, the thiocyano group enters the benzoimidazole ring at position 4, and that 1, 2-dimethylimidazo[5, 4-e] benzo-1, 2, 3-thiadiazole is less basic than its isomer 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole.  相似文献   

2.
By the condensation of -halogenomethyl derivatives of pyrroles with -unsubstituted pyrroles the synthesis of the following unsymmetrical dipyrrolylmethanes has been effected: 5-benzyloxycarbonyl-5-ethoxycarbonyl-3, 3-di(-methoxycarbonylethyl)-4,4-dimethyl-2,2-dipyrrolylmethane (IIIa), 5-benzyloxycarbonyl-5-ethoxycarbonyl-3-(-methoxycarbonylethyl)-4, 4-diniethyl-3-n-propyl-2,2-dipyrrolylmethane(IIIb), 3-acetyl-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIIc), and 3-bromo-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIId). Hydrogenation of the unsymmetrical dipyrrolylmethanes IIIa, b, c, and d has given the corresponding monocarboxylic acids IVa, b, c, and d. The formylation of the dipyrrolylmethanemonocarboxylic acid IVa has given 5-ethoxycarbonyl-5-formyl-3,3-di(-methoxycarbonylethyl)-4, 4-dimethyl-2,2-dipyrrolylmethane (V).For communication II, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 8, pp. 1045–1047, August, 1970.  相似文献   

3.
Research on synthesis of polycyclic spirans of the 1, 6-dioxaspiro-[4, 4]nonane group is continued. Electrolysis of methanol solutions of 2-furylcyclopentanol, 2-(5-methyl-furfuryl)cyclopentanol, and 2-furfuryl-1-indanol, gives, by intramolecular alkoxylation, spiro{perhydrocyclopenta[b]furan-2, 2-(5dihydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-(5-methoxy-5-methyl-2, 5-dihydrofuran)}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxy-2, 5-dihydrofuran)}, hitherto undescribed in the literature. Depending on the conditions, catalytic hydrogenation of these gives: spiro{perhydiocyclopenta[b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{2, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-tetrahydrofuran}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-tetrahydrofuran}.For Part XXXI see [1].  相似文献   

4.
Chlorination of the title compound gave 5- and 3-chloro-2-hydroxy-4,6-dimethoxyacetophenone. The nitration of its acetate, followed successively by reduction, diazotization, and reaction with cuprous chloride, gave the 3-substituted series, 2-acetoxy-4,6-dimethoxy-3-nitroacetophenone, 3-amino-2-hydroxy-4,6-dimethoxyacetophenone, and 3-chloro-2-hydroxy-4,6-methoxyacetophenone, respectively. The orientation of substituents in the products was proved. The amino and chloro members of the isomeric 5-substituted series were availablevia 2-hydroxy-4,6-dimethoxy-5-phenylazoacetophenone, the product of the reaction of the title compound with benzenediazonium chloride.
Nitrierung, Aminierung und Halogenierung von Di-O-methylphloracetophenon
Zusammenfassung Chlorierung der Titelverbindung gab 5- und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Nitrierung des Acetats, gefolgt von Reduktion, Diazotierung und Reaktion mit CuCl ergab die 3-substituierte Reihe: 2-Acetoxy-4,6-dimethoxy-3-nitroacetophenon, 3-Amino-2-hydroxy-4,6-dimethoxyacetophenon und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Orientierung der Substituenten wird diskutiert. Die Amino- und Chlorderivate der isomeren 5-substituierten Reihe sind über 2-Hydroxy-4,6-dimethoxy-5-phenylacetophenon zugängig, dem Produkt der Reaktion der Titelverbindung mit Phenyldiazoniumchlorid.
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5.
The thermal decompositions of glucose and fructose were studied by means of the Derivatograph. From the melting temperature up to 300 these monosaccharides decompose and give brown caramel matter. The TG curves as functions of time were taken at various heating rates (0.5–10/min) by the Derivatograph and the activation energies of the decompositions were determined by Ozawa's method.
Zusammenfassung Die thermische Zersetzung von Glukose und Fruktose wurde mit Hilfe des Derivatographen studiert. Diese Monosaccharide erleiden von der Schmelztemperatur bis zu 300 C eine Zersetzung und ergeben braune Karamelstoffe. Die verschiedenen Zeitspannen zugeordneten TG-Kurven wurden vom Derivatographen bei verschiedenen Aufheizgeschwindigkeiten (von 0.5C/min bis zu 10C/min) registriert und die Aktivierungsenergie der Zersetzung wurde mittels der Methode von Ozawa bestimmt.

Résumé On a étudié la décomposition thermique du glucose et du fructose à l'aide du Derivatograph. Ces monosaccharides subissent une décomposition à partir de la température de fusion jusqu' à 300C en donnant des caramels bruns. Les courbes TG ont été enregistrées en fonction du temps avec diverses vitesses de chauffage (de 0.5 C/min jusqu'à 10C/min) et l'énergie d'activation de la décomposition a été déterminée par la méthode d'Ozawa.

. 300 . ( 0,5/ 10/) .
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6.
3,4,3,4-Tetramethyldiphenyl ether readily forms 2,2-dihalo derivatives on bromination and iodination. Heating 2,2-diiodo-4,5,4,5-tetramethyldiphenyl ether with copper powder or oxidation, of 2,2-dilithio-4,5,4,5-tetramethyldiphenyl ether gives 2,3,7,8-tetramethyldibenzofuran, the structure of which was proved by alternative synthesis from 2,2-dinitroand 2,2-diamino-4,5,4,5-tetramethyldiphenyls.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1597–1599, December, 1972.  相似文献   

7.
The methyl ester and N,N-diethylamide of 2-azido-5-phenyl-4-thiazolecarboxylic acid were obtained by the reaction of the corresponding 4-substituted 2-hydrazino-5-phenylthiazole with NaNO2 in acid media. IR and UV spectroscopy were used to show that the compounds synthesized retain azide form in both the crystalline state and in solution. The reaction of azides with dicarbonyl compounds gave derivatives of 2-[5-methyl-4-acetyl-or 2-[5-methyl-4-ethoxycarbonyl-1,2,3-triazol-1-yl]-5-phenylthiazole-4-carboxylic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 710–714, May, 1993.  相似文献   

8.
The thermal ignition behaviour of various mixtures of organic fuels, magnesium and ammonium nitrate (AN) has been examined by differential thermal analysis technique. It has been observed that the thermal decomposition/ignition of organic fuel-AN mixtures is modified significantly in the presence of magnesium metal. The decomposition characteristics of the binary mixtures of AN with various metals indicate the specific action of magnesium and zinc in lowering the decomposition temperature. A possible explanation for the low temperature decomposition is given in terms of the solid state reaction causing the fusion of AN which further reacts with the metal resulting in a highly exothermic reaction.
Zusammenfassung Mittels DTA wurde das thermische Initiierungsverhalten verschiedener Gemische aus organischen Brennstoffen, Magnesium und Ammoniumnitrat (AN) untersucht. Es wurde festgestellt, daß die thermische Zersetzung/Initiierung von Gemischen aus organischen Brennstoffen und AN durch die Gegenwart von metallischem Magnesium bedeutsam beeinflußt wird. Die Zersetzungscharakteristiken binären Gemische aus AN und verschiedener Metalle zeigen eine spezielle Wirkung von Magnesium und Zink bei der Herabsetzung der Zersetzungstemperatur. Eine mögliche Erklärung für die Zersetzung bei niedrigerer Temperatur kann in Bezug auf die Festkörperreaktion gesehen werden, die das Schmelzen von AN verursacht, welches dann mit dem Metall stark exotherm reagiert.

, (). , / — . . , , .
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9.
A preparative synthesis of the antimetabolite 6-azacytidine is described which involves the amination under mild conditions without the use of an autoclave of 2, 3, 5-tri-O-acyl-4-thip-6-azauridines with the isolation of the intermediate 2, 3, 5-tri-O-acyl-6-azacytidines and subsequent elimination of the protective groups at room temperature.For communication VI, see [10].  相似文献   

10.
A convenient method has been developed for the synthesis of 5-methyl-2-desoxyuridines. Chlorination of 5-O-benzoyl-5-methyluridines with a mixture of Ph3P and CCl4 in DMF affords the 2-desoxy-2-chloro-derivatives, which are then reduced with tributyltin hydride. The crystalline 5-O-benzoyl-5-methyl-2-desoxyuridines were obtained in overall yields of 40–60%. In a similar way, 5-O-benzoyluridine has given 5-O-benzoyl-2-desoxyuridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 246–248, February, 1989.  相似文献   

11.
Conclusions The previously expressed theory that the tricyclic triethyl triphosphite of D-mannitol is 2-ethoxy-4, 5-bis-(2-ethoxy-1, 3, 2-dioxaphospholan-4-yl)-l,3,2-dioxa-4-phospholane was corroborated on the basis of the differential-thermal analysis and31P NMR data.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1390–1395, June, 1972.  相似文献   

12.
2-(2-Selenienyl)benzimidazole has been synthesized by a Weidenhagen reaction and converted into the N-methylated derivative. Electrophilic-substitution reactions (nitration, sulfonation, bromination, chloromethylation, and acylation) in the selenophene ring have been studied. It has been shown that the substituent enters the position of the selenophene ring in most cases. The bromination of 1-methyl-2-(2-selenienyl)benzimidazole in acetic acid produces the 3,5-dibromo derivative, whereas 1-methyl-5(or 6)-bromo-2-(3,5-dibromo-2-selenienyl)benzimidazole is obtained in polyphosphoric acid.For Report 5, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1531–1534, November, 1983.  相似文献   

13.
Zusammenfassung Analog wie in vorherigen Mitteilungen1–4 wurden -Pyridyl-hydrazono-cyanacetylcarbamidsäureäthylester (1), 1-(-Pyridyl)-5-cyan-6-azauracil (2), 1-(-Pyridyl)-6-azauracil-5-carbonsäure (3), deren Thioamid (4), und Amidoxim (5), welches in 1-(-Pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6) überge-führt wurde, hergestellt.
-Pyridylhydrazono-cyanacetylcarbamic acid ethyl ester (1), l-(-pyridyl)-5-cyano-6-azauracil (2), 1-(-pyridyl)-6-azauracil-5-carboxylic acid (3), its thioamide (4) and amidoxime (5) were prepared as described in preceding communications. (5) was converted into l-(-pyridyl)-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracil (6).
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14.
Zusammenfassung Cyclohexanon bzw. Cyclopentanon sowie ihre durch Aldolreaktion entstehenden Dimeren reagieren mit Harnstoff im sauren Medium zu 5,6,7,8-Tetrahydrospiro[cyclohexan-1,4(1H)-chinazolin]-3(2H)-onen (2) bzw. zum Dihydrospiro-(cyclopentan-1,4(1H)-5H-cyclopenta[d]pyrimidin)-2(3H)-on (10). Substituierte Harnsotoffe geben Gemische der isomeren 5,6,7,8-Tetrahydro- und 4a,5,6,7-Tetrahydroverbindungen (2, 3) bzw. 6,7-Dihydro-tH- und 5,6-Dihydro-4aH-verbindungen (10, 11). Charakteristisch für2 (3),10 (11) ist die Reaktivität der Kernstellen 8 bzw. 7 gegenüber elektrophilen Agentien (2f-v, 3f-j, 9 a-i, 10 d-f). Äthylmalonsäurebis-trichlorphenylester bzw. Formaldehyd und prim. Amine führen2 in ein partiell hydriertes 1H-Pyrido[3,2,1-ij]chinazolintrion (6) bzw. 1H-Pyrimido[5,6,1-ij]chinazolinon (7) über. Die 1-Alkylverbindungen (2) geben mit Formaldehyd und primären Aminen Hexahydro-8a-hydroxy-4a,8-propanospiro-(cyclohexan-1,4(1H)-pyrido[4,3-d]pyrimidin)-2(3H)-one (8).
Heterocycles, XXV: tetrahydrospiro [cyclohexane-1,4(1H)-quinazoline]-2(3H)-ones
Cyclohexanone and cyclopentanone, resp., as well as their dimers (formed by aldol reaction) react with urea in the presence of acids to 5,6,7,8-tetrahydrospiro[cyclohexane-1,4-(1H)-quinazoline]-3(2H)-ones (2) and to the dihydrospiro-(cyclopentane-1,4(2H)-5H-cyclopenta[d]pyrimidine)-2(3H)-one (10), resp. Substituted ureas give the isomeric 5,6,7,8-tetrahydro- and 4a,5,6,7-tetrahydro compounds (2, 3), and 6,7-dihydro-5H- and 5,6-dihydro-4aH-compounds (10, 11), resp. Characteristic for2 (3),10 (11) is the reactivity of the nuclear places 8 and 7 with electrophilic agents (2f-v, 3f-j, 9a-i, 10d-f). Ethylmalonic acid bistrichlorophenylester resp. formaldehyde and primary amines react with2 to the partially-hydrogenated 1H-pyrido[3,2,1-ij]-quinazolinetrione (6) and 1H-pyrimido[5,6,1-ij]-quinazolinone (7), resp. The 1-alkyl compounds (2) give with formaldehyde and primary amines hexahydro-8a-hydroxy-4a, 8-propanospiro(cyclohexane-1,4-(1H)-pyrido[4,3-d]pyrimidine)-2(3H)-ones (8).
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15.
1,2,5-Trimethyl-4-(9-fluorenylidene)piperidine, which is formed by condensation of fluorene with 1,2,5-trimethyl-4-piperidone, is converted catalytically to 9(2,5-dimethyl-4-pyridyl)fluorene, from which 2-methylpyrido[4,5-a]fluoranthene and its demethylated analog were obtained by catalytic dehydrocyclization. Oxidation of 9-(2,5-dimethy1-4-pyridyl)fluorene gave 9-(2,5-dimethyl-4-pyridyl)9-fluorenol and fluorene-9-spiro-4-(6-oxo-2-carboxypyrido[4,5-c]-4-6-dihydrofuran). 6-Methyl-2-phenyl-7-(9-fluorenyl)indolizine was synthesized by the Chichibabin method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1090, August, 1978.  相似文献   

16.
The electronic structure of the configurational isomers of 3-3-, 3-5- and 5-5-bis-oxadiazole, and of trans-,-di-(3-3)-, -(3-5)- and -(5-5)-diazolyl-ethylene, was studied by using the ASMO, SCF, CI procedure developed by Pariser, Parr and Pople. The total -electron energy is taken as the measure for ranging the various isomers and their different configurations in a given order of stability.Predictions based on charge distributions and bond orders are in agreement with the chemical behaviour of the known 3-3 and 5-5 isomers, and are therefore regarded as reliable also for the 3-5 compounds, not described in the literature so far.The calculated value of the lowest singlet transition energy agrees with the observed spectra, with a scatter of ±0.20 eV depending on the particular procedure chosen for calculating the pqand (App) integrals. The calculated second singlet transition is found to depend on the procedure chosen for those integrals to such an extent as to make the prediction unreliable.
Zusammenfassung Die Elektronenstruktur der Konfigurationsisomere von 3,3-, 3,5- und 5,5-bis-Oxadiazol und trans-,-di-3,3-, -3,5- und -5,5-Diazolyläthylen wurde mit Hilfe der ASMO-SCF-CI-Methode studiert. Die totale -Elektronenenergie wurde als Maß für die Stabilität der verschiedenen Isomere und ihrer Konfigurationen gewählt.Voraussagen, die auf Ladungsverteilungen und Bindungsordnungen basieren, sind in Übereinstimmung mit dem chemischen Verhalten der bekannten 3,3- und 5,5-Isomere und wurden deshalb auch als zuverlässig für die 3,5-Verbindungen angesehen, die bis jetzt in der Literatur nicht beschrieben sind.Der berechnete Wert für die niedrigste Singulett-Anregungsenergie stimmt mit den beobachteten Spektren bis auf ±0,2 eV überein, abhängig von der Berechnungsart für die pqund (App). Die Anregungsenergie für den zweiten Singulettübergang läßt sich in diesem Rahmen nicht vorhersagen.

Résumé La structure électronique des isomères configurationales des 3-3-, 3-5- et 5-5-bis-oxadiazole, et des trans---di-(3-3)-, -(3-5)- et -(5-5)-diazolyl-ethylène a été étudiée par la méthode ASMO, SCF, CI sélon la forme développée par Pariser, Parr et Pople. L'énergie totale des électrons a été prise comme étalon pour classifier les isomères et leurs differentes configurations sélon un ordre de stabilité.Les déductions que l'on peut tirer de la distribution des charges et des ordres de liaison sont en accord avec les observations chimiques des isomères connus, 3-3 et 5-5; par conséquent on peut considérer raisonables les prédictions que ont été faites sur les isomères 3-5, qui ne sont pas décrites dans la literature jusqu'ici.La valeur calculée pour la première transition de singulet est en bon accord avec le spectre d'absorption observé, l'incertitude due à la procedure choisie pour les integrales pqet (App) étant ±0.20 eV. La deuxième transition de singulet apparait dépendre presque entièrement de la choix faite pour les dites integrales.
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17.
The results of X-ray crystallographic investigations of compounds containing a 2,2-bithienyl fragment are summarized and analyzed. The structural characteristics of unsubstituted bithiophene, 5-monosubstituted, 5,5-, 3,3-, 4,4-, and 3,4-disubstituted, and more highly substituted bithiophenes and also the structure of -conjugated oligothiophene derivatives are considered.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 725–760, June, 2000.  相似文献   

18.
It has been shown that the reaction of monomethinecyanines containing 4-benzopyrylium residues with quaternary salts of derivatives of 2-[(1, 5, 5-trimethylcyclohex-1-en-3-ylidene)-methyl]benzothiazole leads to the scission of the pyrylium ring and the addition of the quaternary salt to the position of scission. The reaction gives tetracarbocyanines containing an o-hydroxyphenyl or an o-acetoxyphenyl substituent in the polymethine chain in addition to a hydrocarbon ring.  相似文献   

19.
Zusammenfassung Synthesen von verschiedenen neuen polyazaheterocyclischen Systemen, wie 11H-Imidazo[1,22,3]pyridazino[6,1-b]-chinazolin-11-on (3), 11H-s-Triazolo[4,32,3]pyridazino[6,1-b]chinazolin-11-on (4), der Isomeren 4H-Pyrido[2,34,5]-pyridazino[6,1-c]-as-triazin (6) und 4H-Pyrido[3,24,5]-pyridazino[6,1-c]-as-triazin (9), Pyrido[3,24,5]pyridazino[1,6-b]benzimidazol (14) sowie Pyrido[3,24,5]-s-triazolo[4,32,3]pyridazino[1,6-a]benzimidazol (15) werden beschrieben.
Syntheses of pyridazines, XXXI: Some new polycyclic azolo and azino-pyridazines
Syntheses of several new polyazaheterocyclic systems are described, i.e. 11H-Imidazo[1,22,3]pyridazino[6,1-b]quinazolin-11-one (3), 11H-s-Triazolo[4,32,3]pyridazino[6,1-b]quinazolin-11-one (4), the isomeric 4H-Pyrido[2,34,5]pyridazino[6,1-c]-as-triazine (6) and 4H-Pyrido[3,24,5]pyridazino[6,1-c]-as-triazine (9), Pyrido[3,24,5]pyridazino[1,6-b]-benzimidazole (14) and Pyrido[3,24,5]-s-triazolo[4,32,3]pyridazino[1,6-a]benzimidazole (15).


Heterocyclen, 69. Mitt.  相似文献   

20.
Several N-substituted 3-phthalimidopiperidine-2,6-diones and 3-(3phthalimido-2,5-dioxopyrrolid-1-yl)piperidine-2,6-dione have been synthesized.  相似文献   

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