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  • 1
    Electronic Resource
    Electronic Resource
    On discrete and continuous norms in Paley-Wiener spaces and consequences for exponential frames (1999)
    Springer
    The journal of Fourier analysis and applications 5 (1999), S. 193-201 
    Details
    ISSN: 1531-5851
    Keywords: Primary 30D15 ; 42C15 ; Secondary 30D10 ; 42C30 ; Paley-Wiener space ; entire functions of exponential type ; exponential frames ; discrete norms ; sampling theorem
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract It is well known that for certain sequences {tn}n∈ℤ the usual Lp norm ∥·∥p in the Paley-Wiener space PW τ p is equivalent to the discrete norm ‖f‖p,{tn}:=(∑ n=−∞ ∞ |f(tn)|p)1/p for 1 ≤ p = 〈 ∞ and ‖f‖∞,{tn}:=sup n∈ℤ|f(tn| for p=∞). We estimate ∥f∥p from above by C∥f∥p, n and give an explicit value for C depending only on p, τ, and characteristic parameters of the sequence {tn}n∈ℤ. This includes an explicit lower frame bound in a famous theorem of Duffin and Schaeffer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01261609
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  • 2
    Electronic Resource
    Electronic Resource
    Preparation of 2,3,5-Tri-O-benzyl-4-thio-L-arabino-furanosides and the Corresponding 4′-Thionucleoside Analogues (1999)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1999 (1999), S. 691-696 
    Details
    ISSN: 1434-193X
    Keywords: Carbohydrates ; 4-Thiofuranosides ; Nucleosides ; Reaction mechanisms ; NOE measurements ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: -1-O-Acetyl-2,3,5-tri-O-benzyl-4-thio-L-arabino-furanose (9) has been prepared from D-xylose via the 1,4-dithio-L-arabino-furanoside 8. The crucial step of the reaction, i.e. the intramolecular cyclization of the open-chain dithioacetal 5, has been achieved in a yield of 90% by applying tetrabutylammonium iodide as promoter. Reaction of 9 with bis(trimethylsilyl)uracil or -thymine led to the benzyl derivatives 12 and 13 from which the deprotected 4′-thionucleoside analogues 14 and 15 have been prepared by debenzylation with boron tribromide.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Formation of δ-Sultines (1,2-Oxathiane 2-Oxides) from Thiolane 1-Oxides (1999)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1999 (1999), S. 943-947 
    Details
    ISSN: 1434-193X
    Keywords: Thiolane 1-oxides ; Oxidations ; δ-Sultines ; [Bis(trifluoroacetoxy)iodo]benzene ; Asymmetric synthesis ; Carbanions ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: -2-(Alkylthio)-2-benzylthiolane 1-oxides (1a, b) and 2-(alkylthio)-2-(α-hydroxybenzyl)thiolane 1-oxides (1c, d) are oxidized with [bis(trifluoroacetoxy)iodo]benzene (PIFA). Under ring enlargement the corresponding cyclic sulfinate esters (δ-sultines) 2 are formed. Only (1R*,2S*)-1b is reactive whereas (1R*,2R*)-1b is not attacked. This observation is explained with the formation of a cyclic intermediate 3.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Electroreduction of organic compounds. 31. Electroreduction of 2- and 3-Chlorodibenzofuran in Deuterated Methanol (1998)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 340 (1998), S. 430-436 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The cathodic reduction of dibenzofuran (2), 2-chlorodibenzofuran (4), and 3-chlorodibenzofuran (1) in deuterated methanol is investigated. The Birch-type reduction product 1,4-dibenzofuran (3) is formed from 1 via 2, whereas 2-chloro-1,4-dihydrodibenzofuran (5) is obtained as by-product besides 3 from 4 as starting compound. Deuterium is only incorporated into the reduction products if CH3OD or CD3OD but not if CD3OH are used. This observation is strongly indicative of a polar mechanism involving protonation rather than a radical mechanism with hydrogen atom abstraction to be operative.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19983400505
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  • 5
    Electronic Resource
    Electronic Resource
    Reaction of the Carbanions of 2-(Alkylthio)thiolane 1-Oxides with Oxiranes (1999)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1999 (1999), S. 1481-1488 
    Details
    ISSN: 1434-193X
    Keywords: Thiolane 1-oxides ; Carbanions ; Oxiranes ; Asymmetric synthesis ; X-ray structure ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: -Carbanions of the 2-(alkylthio)thiolane 1-oxides 1 and 2 are generated and subjected to reaction with the epoxides 3-5. The resulting carbinols 6-11 are formed with high α diastereoselectivity, which is explained by a stabilization of the trans configuration of the carbanions in the activated complex. A minor γ stereoselectivity is also observed in case of the reactions with 4 and 5. The pure enantiomers (1S,2S,2′S)-9a and (1R,2R,2′S)-11b were obtained from 2 and (S)-4 or (R)-5, respectively, and their configurations were proved by X-ray structural analyses.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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    Paper (German National Licenses)
  • 6
    Electronic Resource
    Electronic Resource
    Über die Oxydationsprodukte von Thiocarbonsäureamiden, XII. Oxydationsreaktionen an Thiolimidestern und N-Heteroaromaten mit α- und γ-ständigen Thiocarbonylgruppen (1966)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 695 (1966), S. 77-86 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thiolimidester 1 werden durch Perbenzoesäure zu Amiden oxydiert. Pyridinthione-(2), Pyridinthion-(4) und Purinthione-(6) ergeben mit Wasserstoffperoxid S-Oxide, die aber leicht zu Disulfiden (z. B. 20, 24, 31) sowie in basischem Milieu zu Sulfonsäuren (z. B. 21, 25, 29) weiterreagieren. Das 6-Thio-theophyllin-S-oxid (38) wurde rein isoliert.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.19666950110
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  • 7
    Electronic Resource
    Electronic Resource
    Über die Oxydationsprodukte von Thiocarbonsäureamiden, XIV. Reaktion aromatischer Thiolactame und einiger ihrer S-Oxide mit Diazomethan (1966)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 698 (1966), S. 113-121 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Diazomethan überführt 6-Thio-theophyllin (6) in 6-Thio-coffein (7) und Chinazolinthione-(4) (8) in 4-Methylmercapto-chinazoline (9). Aus 6-Thio-theophyllin-S-oxid (12) entsteht intermediär 6-Thio-coffein-S-oxid (13), das sich zu 6-Thio-coffein (7) und Coffein (14) zersetzt.  -  2-tert.-Butyl-chinazolinthion-(4)-S-oxid (2) wird dagegen am Sauerstoffatom methyliert, wobei sich der Sulfensäuremethylester bildet, dessen Struktur chemisch sowie durch sein IR-, Massen- und Protonenresonanzspektrum gesichert wird.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.19666980113
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  • 8
    Electronic Resource
    Electronic Resource
    Über die Oxydationsprodukte von Thiocarbonsäureamiden, XIII. Oxydationsreaktionen an Chinazolinthionen-(4) (1966)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 695 (1966), S. 87-97 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Chinazolinthione-(4) (2) lassen sich zu S-Oxiden (7) und Disulfiden (9) oxydieren, wenn sie in 3-Stellung unsubstituiert sind; anderenfalls erhält man Chinazolone-(4) (1).
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.19666950111
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  • 9
    Electronic Resource
    Electronic Resource
    Direkte Darstellung von Thioamiden aus Säurechloriden und Aminen (1968)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 716 (1968), S. 209-211 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-substituierte Thioamide lassen sich in einer Stufe aus Aminen, Acylierungsmitteln und Phosphorpentasulfid darstellen.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.19687160131
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