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  • 1990-1994  (3)
  • 1970-1974  (11)
  • 1955-1959  (12)
  • 1890-1899  (5)
  • Inorganic Chemistry  (30)
  • Cell & Developmental Biology
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 668-670 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterocyclic Dicarboxylic Acid Esters, II. Reaction of 2,3-Bis(methoxycarbonyl)-4,5-dihydrofurans with Hydrazine and 1,2,3,6-Tetrahydropyridazine.  -  Synthesis of 3-Hydroxy-4-(2-hydroxyalkyl)-5-pyrazolcarboxylic Acid DerivativesIn contrast to the 5,6-dihydro-4H-pyran and furan dicarboxylic acid esters 1 and 4, 2,3-bis-(methoxycarbonyl)-4,5-dihydrofurans 10a-c upon treatment with hydrazine do not yield the dihydrazides but undergo ring cleavage to the 3-hydroxy-4-(2-hydroxyalkyl)-5-pyrazolecarboxylic acid hydrazides 11a-c. Under mild conditions the intermediate ester 12a can be isolated. 12a as well as 11a, c can be hydrolyzed to the carboxylic acids 14a, b. Acyllactone rearrangement of the α-alkoxalyllactones 9a, d with hydrazine also yields the esters 12a, b. I.r. and n.m.r. data are discussed.
    Notes: Bei der Behandlung der 2,3-Bis(methoxycarbonyl)-4,5-dihydrofurane 10a-c mit überschüssigem Hydrazinhydrat entstehen, im Gegensatz zum Verhalten der analogen 5,6-Dihydro-4H-pyran- und Furandicarbonsäureester 1 und 4, nicht die entsprechenden Dihydrazide, sondern es tritt Ringöffnung zu den 3-Hydroxy-4-(2-hydroxyalky)-5-pyrazolcarbonsäure-hydraziden 11a-c ein. Unter schonenden Bedingungen läßt sich der 5-Pyrazolcarbonsäureester 12a isolieren. Sowohl 12a als auch 11a, c lassen sich zu den Carbonsäuren 14a, b verseifen. Die Ester 12a, b entstehen ebenfalls in einer Acyllacton-Umlagerung der α-Alkoxalyl-lactone 9a, d mit Hydrazin. Die IR- und NMR-Daten der dargestellten Verbindungen werden diskutiert.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 721-724 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterocyclic Dicarboxylic Acid Esters, III. Reaction of Dimethyl 4,5-Dihydro-2,3-furandicarboxylates with 1,2-Diamines.  -  Synthesis of 3-(5-Alkyl-2-2oxotetrahydro-3-furanylidene)-2-quinoxalinones, -2-pyrazinones, and -1,4-diazepine-2-onesTreatment of the dihydrofurandicarboxylic acid esters 4a-c with 1.2-diamines does not result in normal ester aminolysis but in ring cleavage followed by lactonization. According to the diamine used the quinoxalinones 14, 15a-c, the pyrazinones 11-c, and the diazepinones 16a, c are obtained. The independent synthesis of the compounds 11a, 14a, 15a by condensation of the different diamines with α-ethoxalyl-γ-butyrolactone as well as the tabulated i. r. and n. m. r. data confirm the proposed structures.
    Notes: Dihydrofurandicarbonsäureester vom Typ 4a-c reagieren mit 1,2-Diaminen nicht im Sinne einer normalen zweifachen Ester-Aminolyse, sondern unter Ringöffnung und anschließender Lactonisierung. Entsprechend dem eingesetzten Diamin erhält man die Chinoxalinone 14.15a-c, die Pyrazinone 11a-c sowie die Diazepinone 16a, c. Die unabhängigen Synthesen der jeweiligen Grundkörper 11a, 14a, 15a durch Kondensation der verschiedenen Diamine mit α-Äthoxalyl-γ-butyrolacton, wie auch die aufgeführten IR- und NMR-Daten bestätigen die angenommenen Strukturen.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 105 (1972), S. 969-974 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sugar-Siloxanes, II Synthesis of some Silicium-containing Sugar DerivativesSome sugar-silicium compounds have been synthesized by addition of methyldiethoxysilane to unsaturated monosaccharide derivatives. Among others the hitherto unknown compounds 6.7-Dideoxy-1.2;3.4-di-O-isopropylidene-α-D-galacto-hept-6-enopyranose (2) with a straight carbon chain and 3-O-acetyl-3-C-ethynyl-1.2;5.6-di-O-isopropylidene-α-D-allofuranose (8b) as well as ethynediyl-3-C.3′-C-bis(3-O-acetyl-1.2;5.6-di-O-isopropylidene-α-D-allofuranose) (9b) with branched carbon chains were used as starting materials. No addition, probably due to steric hindrance, was observed with 9b.
    Notes: Eine Reihe von Zucker-Siliciumverbindungen wurde durch Addition von Methyldiäthoxysilan an ungesättigte Monosaccharidderivate dargestellt. Als Ausgangsprodukte dienten unter anderen die bisher unbekannten Verbindungen 6.7-Didesoxy-1.2;3.4-di-O-isopropyliden-α-D-galakto-hept-6-enopyranose (2) mit unverzweigtem sowie 3-O-Acetyl-3-C-äthinyl-1.2;5.6-di-O-isopropyliden-α-D-allofuranose (8b) und Äthindiyl-3-C-.3′-C-bis-[3-O-acetyl-1.2;5.6-di-O-isopropyliden-α-D-allofuranose] (9b) mit verzweigtem Kohlenstoffgerüst. An die Verbindung 9b ließ sich, offenbar aus sterischen Gründen, kein Silan addieren.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 929-934 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterocyclic Dicarboxylic Acid Esters, I. Synthesis and Reactivity of 2-Methyl-3,4-dihydro-ZH-pyrano[2,3-d]pyridazines6-Methyl-2,3-bis(methoxycarbonyl)-5,6-dihydro-4H-pyrane (2a) reacts with hydrazine to give the dihydrazid 3 which can be converted to 2-niethyl-3,4,5,6,7,8-hexahydro-2H-pyrano [2,3-d]-pyridazine-5,8-dione (4) under elimination of hydrazine. Treatment of 4 with POCl3/pyridine yields the 5,8-dichloropyranopyridazine 5. The reactivity of this compound to nucleophilic agents is studied and discussed. I. r. and n. m. r. data are given.
    Notes: 6-Methyl-2,3-bis(methoxycarbonyl)-5,6-dihydro-4H-pyran (2a) setzt sich mit Hydrazinhydrat zum Dihydrazid 3 um, welches unter Hydrazinabspaltung in das 2-Methyl-3,4,5,6,7,8-hexahydro-2H-pyrano[2,3-d]pyridazin-5,8-dion (4) übergeht. Durch Behandlung von 4 mit POCl3/Pyridin erhält man das 5,8-Dichlorpyranopyridazin 5, dessen Reaktivität gegenüber nucleophilen Agentien untersucht und diskutiert wird. Die IR- und NMR-Daten der erhaltenen Verbindungen werden aufgeführt.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 92 (1959), S. 2460-2468 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch alkalische Hydrolyse und durch Synthese aus Trimethylamin, Formaldehyd und Benzolsulfochlorid wird bewiesen, daß es sich bei dem „Vorländerschen Salz“ nicht um Benzolsulfonyl-trimethylammoniumchlorid, sondern um Benzolsulfonyloxymethyl-trimethyl-ammoniumchlorid („Benzolsulfonyl-formocholinchlorid“) handelt.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 3533-3539 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterocyclic β-Enamino Esters, X. The Reactivity of Ethyl 2-Amino-3-quinolinecarboxylate against Isocyanates, Isothiocyanates, and Lactim EthersEthyl 2-amino-3-quinolinecarboxylate (6) cyclizes in the presence of catalytic amounts of alcoholic potassium hydroxide with the isocyanates 7a-d to yield the 2,4-dioxopyrimido-[4,5-b]quinolines 8a-d. Under similar conditions p-toluenesulfonyl isocyanate affords only the p-tosylurea 10, which does not undergo further ring closure in contrast to the phenylurea 4. Treatment of 6 with isothiocyanates (7e, f) leads to 2-thioxopyrimido[4,5-b]quinolines (8e, f). 6 reacts with diethyl malonate to give the benzo[b][1,8]naphthyridine 5. - Treatment of 6 with ∊-caprolactim methyl ether yields the azepino[1′,2′:1,2]pyrimido[4,5-b]quinoline 12 and condensation with 2-methoxy-1,4,5,6-tetrahydropyrimidine gives the pyrimido[l′,2′:1,2]-pyrimido[4,5-b]quinoline 11. - I. r. and n. m. r. data are discussed.
    Notes: 2-Amino-3-chinolincarbonsäure-äthylester (6) cyclisiert in Gegenwart katalytischer Mengen alkoholischer Kaliumhydroxid-Lösung mit den Isocyanaten 7a-d zu 2,4-Dioxopyrimido-[4,5-b]chinolinen (8a-d). Mit p-Toluolsulfonylisocyanat wird lediglich der N-Tosylharnstoff 10 isoliert, der im Gegensatz zum Phenylharnstoff 4 nicht zum Pyrimido[4,5-b]chinolin cyclisiert werden kann. Mit den Isothiocyanaten 7e, f bilden sich analog die 2-Thioxopyrimido-[4,5-b]chinoline 8e, f. Aus 6 und Malonester erhält man das Benzo[b][1,8]naphthyridin 5.-6 reagiert mit ∊-Caprolactim-methyläther zu dem Azepino[l′,2′:1,2]pyrimido[4,5-b]chinolin 12 und mit 2-Methoxy-1,4,5,6-tetrahydropyrimidin zum Pyrimido[l′,2′:1,2]pyrimido[4,5-b]-chinolin 11. - IR- und NMR-Daten werden diskutiert.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Developmental Dynamics 199 (1994), S. 103-115 
    ISSN: 1058-8388
    Keywords: Nanos ; Maternal effect ; Posterior determinant ; RNA localization ; Grandchildless mutations ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The Drosophila gene nanos is required for two processes. During oogenesis, nanos function is required for the continued production of egg chambers, and nanos is expressed in the early germarium. During embryogenesis, nanos is required maternally to specify abdominal segmentation. Nanos shares this latter function with nine other genes, collectively known as the posterior group. Of this group, nanos encodes a determinant, and is localized as an RNA to the posterior pole of early embryos. This RNA is translated to form a gradient of nanos protein with highest concentrations at the posterior. Analysis of the distribution of nanos gene products in embryos mutant for posterior group genes shows that eight of these genes are required for localization, but not stability, of the nanos RNA. Embryos mutant for posterior group alleles which produce weak abdominal phenotypes show reduced amounts of localized nanos RNA. This correlation between nanos RNA localization and abdominal phenotype suggests that nanos acts as a localization-dependent posterior determinant. Localization of nanos is not affected by mutations in bicoid or torso, confirming that the three maternal systems of anterior-posterior determination initially act independently. © 1994 Wiley-Liss, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 90 (1957), S. 1000-1007 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Im Extrakt aus den reifen Schoten des Johannisbrotes wurden neben Xylose, Fructose, Glucose und Saccharose mehrere weitere Oligosaccharide nachgewiesen. Von diesen. wurden zwei reduzierende Disaccharide auch präparativ isoliert und als Xylosido-glucose und Fructosido-glucose gekennzeichnet. Das xylosehaltige Disaccharid erwies sich nach den Eigenschaften des Heptaacetats als identisch mit Primverose; das fructosehaltige Disaccharid, das bisher noch nicht beschrieben war und Ceratose genannt wird, konnte durch Kristallisation eines Azobenzolsulfonylhydrazons sowie eines Oktaazobenzolcarbonsäureesters charakterisiert werden. - Im Laufe der Reifung der Johannisbrotfrucht nimmt die Zahl der nachweisbaren Zucker ständig zu.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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