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1.
2-Diethylamino-3H-phenothiazin-3-one was dealkylated to 2-ethylamino-3H-phenothiazin-3-one either by photolysis or pyrolysis.
Entalkylierung von 2-Diethylamino-3H-phenothiazin-3-on (Kurze Mitteilung)
Zusammenfassung Die Titelverbindung wurde durch Photolyse oder Pyrolyse zu 2-Ethylamino-3H-phenothiazin-3-on entalkyliert.
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2.
Nitration ofN-3-chloroalkoxy-2-hydroxypropyl-N-alkylsulfamates gave the correspondingN-3-chloroalkoxy-2-nitroxypropyl-N-alkylnitramines. Azidation of the latter resulted inN-azido-3-azidoalkoxypropyl-N-alkylnitramines. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 673–676, April, 1998.  相似文献   

3.
Summary 4,5-Dihydro-5,5-dimethyl-3-oxo-3H-1,2,4-triazole (1) is converted to the title azoxy compound4 by peroxytrifluoroacetic acid. The structure assignment of4 is based on an X-ray analysis.Ab initio calculations were employed to rationalize the reaction path leading to the triazole-1-oxide4 and not to the expected regioisomer triazole-2-oxide3.
4,5-Dihydro-5,5-dimethyl-3-oxo-3H-1,2,4-triazol-1-oxid. Das unerwartete Regioisomere
Zusammenfassung 4,5-Dihydro-5,5-dimethyl-3-oxo-3H-1,2,4-triazol (1) wird mit Trifluorperessigsäure in die Titel-Azoxy-Verbindung4 umgewandelt. Die Strukturzuordnung von4 basiert auf einer Röntgenstrukturanalyse. Mittelsab initio-Rechnungen wird versucht zu erklären, weshalb die Reaktion zum Triazol-1-oxid4 und nicht zum erwarteten regioisomeren Triazol-2-oxid3 führt.
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4.
A new synthesis ofE- andZ(-)(1R,3S)-2,2-dimethyl-3-(3,3,3-trifluoro-2-chloropropen1-yl)cyclopropanecarboxylic acids from (+)-3-carene in 21 % total yield was carried out.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 517–518, March, 1995.  相似文献   

5.
Summary 4-Dimethylamino-5,6-dihydro-2H-thiopyran-2-thiones (1) were alkylated to N,N-dimethyl-6-methylthio-2H-thiopyran-4(3H)-iminiumiodides (2). Aminolysis of the latter with ammonia led to 6-dimethylamino-2H-thiopyran-4(3H)-iminiumiodides (3) which were hydrolyzed to 3-amino-N,N-dimethyl-2,4-pentadienthioamides (4). Ring closure with sulfur gave 3-aminothiophene-2-thioamides (5). The configurations of the pentadienthioamides (4) have been investigated by NOE experiments. The structures of the thiophene-2-thioamides (5) were established by means of two-dimensional NMR techniques.
Synthese von 3-Aminothiophen-2-thiocarboxamiden
Zusammenfassung 4-Dimethylamino-5,6-dihydro-2H-thiopyran-2-thione (1) wurden zu N,N-Dimethyl-6-methylthio-2H-thiopyran-4(3H)-iminiumiodiden(2) alkyliert. Die Umsetzung mit Ammoniak führte zur Bildung von 6-Dimethylamino-2H-thiopyran-4(3H)-iminiumiodiden (3). Diese wurden zu 3-Amino-N,N-dimethyl-2,4-pentadienthioamiden (4) hydrolysiert. Beim Erhitzen mit Schwefel erfolgte Cyclisierung zu 3-Aminothiophen-2-thiocarboxamiden (5). Die Konfiguration der Pentadienthioamide (4) wurde mit NOE-Messungen untersucht, die der Thiophen-2-thiocarboxamide (5) mit Hilfe zweidimensionaler NMR-Methoden aufgeklärt.
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6.
Several (E)- and (Z)-3-styrylchromones were prepared by two different methodologies, the Wittig reaction of chromone-3-carboxaldehyde with benzylic ylides and the Knoevenagel condensation of chromone-3-carboxaldehyde with phenylacetic acids in the presence of potassium tert-butoxide under microwave irradiation. The Knoevenagel reaction followed by a decarboxylation offered an efficient and diastereoselective method for preparing (E)-3-styrylchromones in a shorter reaction time. It was also demonstrated that phenylacetic acid can also be substituted with success by phenylmalonic acid. The stereochemistry of all products was assigned by NMR experiments. Correspondence: Artur M. S. Silva, Chemistry Department, University of Aveiro, 3810-193 Aveiro, Portugal.  相似文献   

7.
A microbial strain, Vagococcus sp. B32, was isolated and applied to degrade p-chloronitrobenzene (p-CNB) in aqueous solutions. Three degradation methods: biodegradation, direct γ-irradiation and 60Co-γ pre-irradiation with biodegradation by B32 were carried out. The decrease of p-CNB and the net increase of Cl were investigated to evaluate the degradation efficiency. The preliminary results showed that the combined method of pre-irradiation with biodegradation of B32 was more effective than the two others.  相似文献   

8.
Summary A short and economical synthesis of 3-deoxy-D-arabino-2-heptulosonic acid (4) and 3-deoxy-D-arabino-2-heptulose (kamusol,8) has been developed. In the key step of the reaction sequence, the indium mediated allylation ofD-erythrose in an aqueous solvent system was utilized generating a seven carbon backbone which was further transformed into the title compounds.
Indiumunterstützte Allylierung in der Kohlenhydratchemie: Eine einfache Synthese von 3-Desoxy-D-arabino-2-heptulosonsäure (DAH) und 3-Desoxy-D-arabino-2-heptulose (Kamusol)
Zusammenfassung Eine kurzer und ökonomischer Syntheseweg für 3-Desoxy-D-arabino-2-heptulosonsäure (4) und 3-Desoxy-D-arabino-2-heptulose (Kamusol,8) wurde entwickelt. Im Schlüsselschritt der Synthesesequenz wurde die indiumunterstützte Allylierung vonD-Erythrose in wäßrigen Reaktionsmedien angewendet. Das mittels dieser Methode auf sieben Kohlenstoffatome verlängerte Kohlenhydrat-Grundgerüst konnte einfach in die Titelverbindungen übergeführt werden.
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9.
PrimaryN-nitramines react with vinyl ethers to give 3-nitro-3-azalk-2-yl ethers. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 621–623, March, 1999.  相似文献   

10.
The reaction of 2-methyl-3-(4-tolyl)-4(3H)-quinazolone with benzil produces 2-[(Z)-3-oxo-2,3-diphenylprop-1-enyl]-3-(4-tolyl)-4(3H)-quinazolone, which is readily transformed into 2-(3,3-diphenylsuccinimido)-N-(4-tolyl)benzamide on dissolution in organic water-containing solvents. The rearrangement mechanism was suggested and investigated by the quantum chemical PM3 method. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 146–151, January, 2007.  相似文献   

11.
5-Alkyl(aryl)-3-arylidene-3H-pyrrolin-2-ones were synthesized by ammonolysis of their O-heteroanalogs or by the reactions of 5-alkyl(aryl)-3H-pyrrolin-2-ones with aromatic aldehydes. The structures of the compounds obtained were confirmed by 1H NMR spectra.  相似文献   

12.
The acylation of benzo[b]furan-, benzo[b]thiophene, and indolyl-3-acetic acid arylamides using acetic anhydride in the presence of 70% perchloric acid occurs at the -position of the heterocycle to give 2-acetylbenzo[b]furan-, 2-acetylbenzo[b]thiophene, and 2-acetylindolyl-3-acetic acid arylamides. Depending on the amount of perchloric used in the reaction they undergo cyclodehydration to 3-arylamino-1-methylhetero[2,3-c]pyrilium salts and to N-aryl-1-methyl-3(2H)hetero[2,3-c]pyridones.  相似文献   

13.
The effect ofmeta-substituents in the aromatic ring on the route of Claisen rearrangement ofN-(pent-3-en-2-yl)-3-fluoro(or 3-trifluoromethyl, 3,4-difluoro)anilines induced by ZnCl2 was investigated. The formation of two possibleortho-alkenylated reaction products was observed. The ratio of these isomers depends on the nature of the acid catalyst. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 188–190, January, 1998.  相似文献   

14.
The treatment of 3-isocyano-o-carboranes with an alkali solution in alcohol results in the regioselective splitting out of a boron atom from position 6 of theo-carborane nucleus to give 3-isocyano-nido-7,8-dicarbaundecaborate salts, in which the isonitrile group is attached to the boron atom of thenido-polyhedron anion. 3-Isocyano-nido-7,8-dicarbaundecaborate salts are new isonitrile ligands in transition-metal complexes. Complexes with chromium, molybdenum, tungsten, and iron compounds have been obtained.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1458–1460, August, 1993.  相似文献   

15.
Aminals of aromatico-hydroxyaldehydes react when heated with terminal acetylenes to form, depending on the reaction conditions and the nature of the starting compounds, 1,3-substituted propargylamines or 3H-2-vinylidene-3-aminobenzofuran derivatives, the structures of which were established by X-ray diffraction.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 455–460, March, 1994.  相似文献   

16.
A practical method for preparing methyl 3β-amino-3-dexoybetulinate that is based on column chromatographic separation of 3α- and 3β-t-butoxycarbonates and subsequent removal of the protecting group using formic acid is proposed. The structure of methyl 3β-N-(t-butoxycarbonyl)-3-deoxybetulinate was established by an x-ray structure analysis. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 488–490, September-October, 2008.  相似文献   

17.
It was shown that 3-alkoxy-2-nitroxypropyl-N-alkylnitramines can be prepared by nitration of the corresponding 3-alkoxy-2-hydroxypropyl-N-alkylsulfamates. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1987–1989, November, 1997.  相似文献   

18.
An efficient system for the production of (R)-hydroxyalkanoicacids (RHAs) was developed in natural polyhydroxyalkanoate (PHA)-producing bacteria and recombinant Escherichia coli. Acidic alcoholysis of purified PHA and in vivo depolymerization of PHA accumulated in the cells allowed the production of RHAs. In recombinant E. coli, RHA production was achieved by removing CoA from (R)-3-hydroxyacyl-CoA and by in vivo depolymerization of PHA. When the recombinant E. coli harboring the Ralstonia eutropha PHA biosynthesis genes and the depolymerase gene was cultured in a complex or a chemically defined medium containing glucose, (R)-3-hydroxybutyric acid (R3HB) was produced as monomers and dimers. R3HB dimers could be efficiently converted to monomers by mild alkaline heat treatment. A stable recombinant E. coli strain in which the R. eutropha PHA biosynthesis genes were integrated into the chromosome disrupting the pta gene was constructed and examined for the production of R3HB. When the R. eutropha intracellular depolymerase gene was expressed by using a stable plasmid containing the hok/sok locus of plasmid R1, R3HB could be efficiently produced.  相似文献   

19.
TlFe3Te3 is hexagonal, space groupP63/m–C 2h 6 ,a=9.350(2) Å,c=4.2230 (7) Å,Z=2. Iron and tellurium atoms occupy the positions 6 (h) withx=0.170,y=0.149 andx=0.046,y=0.357 respectively. Thallium atoms are situated in 2 (d). The structure was determined on the basis of single crystal data obtained form a four circle diffractometer. Refinement yielded andR-value of 4.8% for an asymmetric set of 267 reflections. TlFe3Te3 is a new structure type. The structure and its relations to the Mn5Si3–, the Nb3Te4-and the Tl x V6S8-type are discussed.
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20.
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   

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