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  • 1
    Electronic Resource
    Electronic Resource
    Isomere Diamino-alkoxy-pyridin-carbonitrile — ihre Trennung und Verwendung als Kupplungskomponenten (1983)
    Springer
    Monatshefte für Chemie 114 (1983), S. 973-982 
    Details
    ISSN: 1434-4475
    Keywords: Azo Dyes ; Diamino-alkoxy-pyridine-carbonitriles ; UV-VIS spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The isomeric 4,6-diamino-2-alkoxy- (3), and 2,4-diamino-6-alkoxy-3-pyridine-carbonitriles (4) are obtained by treatment of 2-amino-1,1,3-tricyanopropene (1) with sodium alkoxides. Separation is based on their differentpK a -values (3 a=2.01,4 a=4.17). Coupling reaction of3 a-c with benzenediazonium chloride in strong acidic medium leads to the yellow azo dyes5 a-c, whereas coupling of4 a requires a buffered solution (pH 4–6) to yield6. The UV-VIS spectra of the isomer pyridines and the azo dyes are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00799957
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  • 2
    Electronic Resource
    Electronic Resource
    Diphenylethanediamine (DPEDA) derivatives as chiral selectors: IV. A comparison of 3,5-dinitrobenzoylated (S,S)- and (S,R)-DPEDA-derived chiral stationary phases with Pirkle's standard (R)-phenylglycine-derived phase in normal phase HPLC (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 6 (1994), S. 116-128 
    Details
    ISSN: 0899-0042
    Keywords: chiral recognition ; diphenylethylendiamine ; benzodiazepines ; amino acids ; phthalide ; sulfoxide ; drug ; carbinol ; tetrahydropyrimidine ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Undecanoyl bound 3,5-dinitrobenzoyl-(S,R)-1,2-diphenylethane-1,2-diamine [(1S,2R)-DNB-DPEDA] as chiral selector (SO) has been synthesized and used as a chiral stationary phase (CSP II) for normal-phase enantioselective HPLC. It is compared with the already published diastereomeric (1S,2S)-DNB-DPEDA-derived CSP I and with the “standard” Pirkle DNB-(R)-phenylglycine-derived CSP III. Chromatographic data for about 100 racemic analytes reveal that CSP II is able to separate especially well enantiomers of derivatized aromatic carboxylic acids and analytes having a benzyl substituent bound at the chiral center. However, CSP I was found to be superior to CSP II and III in its general applicability and its ability to resolve enantiomers of heterocyclic drugs. © 1994 Wiley-Liss, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/chir.530060212
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  • 3
    Electronic Resource
    Electronic Resource
    Diphenylethanediamine (DPEDA) as chiral selector: VII. Efficient HPLC resolution of a series of underivatized diarylcarbinols on a chiral stationary phase based on C5-amide-bonded N-3,5-dinitrobenzoyl-DPEDA (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 8 (1996), S. 490-493 
    Details
    ISSN: 0899-0042
    Keywords: diarylcarbinol ; arylarylmethanol ; chiral stationary phase ; enantioseparation ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fast and efficient baseline separation of asymmetrically substituted diarylmethanols and 1,1-diarylethanols was achieved on an endcapped, amide-linked N-3,5-dinitrobenzoylated, (R, R)-1,2-diphenyl-1,2-ethanediamine-derived chiral stationary phase (CSP). Optimal enantioselectivities on this CSP were obtained using 1% 2-propanol in n-heptane as the mobile phase. Enantiorecognition was found to be governed by π-basicity and the substitution pattern of the aromatic substituents. © 1996 Wiley-Liss, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Synthesis and effects on peripheral thyroid hormone conversion of (R)-4-hydroxypropranolol, a main metabolite of (R)-propranolol (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 3 (1991), S. 145-150 
    Details
    ISSN: 0899-0042
    Keywords: hyperthyroidism ; (R)-4-hydroxypropranolol ; peripheral conversion ; metabolites of propranolol ; negative chronotropic effect ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The inhibiting effect of (R,S)-propranolol on peripheral T4/T3 conversion can be related to the (R)-isomer. The intention of this study is to clarify if (R)-4-hydroxypropranolol, a main metabolite of (R)-propranolol, develops the same or even a stronger effect on peripheral thyroxine metabolism as the parent drug. (R)-4-hydroxypropranolol was synthesized via (R)-4-methoxypropranolol and their optical purity was checked chromatographically. Twenty patients suffering from hyperthyroidism were divided into five groups and treated with (R)-4-hydroxypropranolol · HCl in dosages from 12 to 75 mg per day in a placebo controlled study over a period of 5 days. The serum hormone levels and resting pulse rate were measured. No significant changes of thyroid parameter could be observed but a significant decrease of resting pulse rate under treatment with 75 mg (R)-4-hydroxypropranolol occurred. It could be concluded that (R)-4-hydroxypropranolol possesses negative chronotropic effects but develops no changes in thyroid hormone metabolism in hyperthyroid patients.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/chir.530030212
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  • 5
    Electronic Resource
    Electronic Resource
    The chemical and thermal stability of the acetamido group of (R)- and (S)-atenolol: Synthetic and chromatographic studies (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Chirality 6 (1994), S. 411-419 
    Details
    ISSN: 0899-0042
    Keywords: atenolol ; nitrile formation ; stability ; chromatography ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The chemical stability of the acetamido moiety of the β-blocker atenolol toward possible dehydration causing a nitrile formation during an acid-catalyzed chiral derivatization procedure with O,O′-(R,R)-diacylated tartaric acid anhydrides was elucidated. All the necessary reference compounds including the oxazolidine-2-one derivatives of the respective aminopropanols were synthesized, their structures confirmed by various spectroscopic methods, and chromatographically compared using HPLC and GC-MS. In the course of this work it was shown that the acetamido moiety of atenolol is quite stable toward dehydrating agents but shows a significant thermolability, e.g., in the injection system of a GC, which leads to the dehydrated form of atenolol namely, “nitriloatenolol.” © 1994 Wiley-Liss, Inc.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/chir.530060509
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  • 6
    Electronic Resource
    Electronic Resource
    Thermochrome polymere und oligomere. 1. Synthese und charakterisierung (1979)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 79 (1979), S. 207-221 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Polymers and oligomers of diethanolaniline were reacted with 2-dicyanomethylen-1,3-indandione to yield colourless adducts, which can be converted to deep blue merocyanine dyes by heating to 80-120°C.
    Notes: Durch Umsetzung von Polymeren und Oligomeren des Diäthanolanilins mit 2-Dicyan-methylen-1,3-indandion werden farblose Addukte erhalten, die beim Erwärmen auf 80-120°C in tiefblaue Merocyaninfarbstoffe übergehen.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1979.050790118
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  • 7
    Electronic Resource
    Electronic Resource
    Thermochrome polymere und oligomere. II. Kinetik und mechanismus der farbstoffbildungTeil I s. Angew. Makromol. Chem. 79 (1979) 207 (1979)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 79 (1979), S. 223-236 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: 2-Dicyanomethylene-1,3-indandione forms colourless adducts with higher molecular derivatives of N,N-Diethanolaniline which thermally decompose to dark blue dyes. The rate of the dye formation is determined UV-photometrically and is compared with rates for monomeric model compounds. It is shown that reaction rates can be correlated with the solvent polarity parameter ET′ (r = 0,928). Due to kinetic data a carbanionic mechanism is suggested.
    Notes: Die Geschwindigkeit der Bildung eines tiefblauen Farbstoffs aus ungefärbten Addukten des 2-Dicyanmethylen-1,3-indandions mit hohermolekularen Derivaten des Diäthanolanilins wurde photometrisch gemessen und mit den Werten monomerer Modellsubstanzen verglichen. Die Geschwindigkeitskonstanten sind mit dem Parameter ET der Lösungsmittelpoläritat korrelierbar (r = 0,928). Auf Grund der kinetischen Daten wird auf einen Carbanion-Mechanismus geschlossen.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1979.050790119
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  • 8
    Electronic Resource
    Electronic Resource
    Tartaric Acid Chloralides: Isolation and X-ray Analysis of the Third Existing Stereoisomer. Force-Field and AM1 Calculation of all Six Possible Structures (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1203-1205 
    Details
    ISSN: 0009-2940
    Keywords: AM1 calculations ; Chloralide ; Dioxolane ; Force-field calculations ; Tartaric acid ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Isolation of a third diastereoisomer (1c) of (R,R)-tartaric acid chloralide is described. A comparison of structural data derived by X-ray analysis with calculated parameters is given. Structures are generated by the ALCHEMY force-field program as well as by AM1 calculations.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220629
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  • 9
    Electronic Resource
    Electronic Resource
    Synthesen mit Nitrilen, LXVI Synthese des 1,2,3,4-Tetrachlorpentafulven-6,6-dicarbonitrils (1983)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1983 (1983), S. 154-158 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,2,3,4-Tetrachloropentafulvene-6,6-dicarbonitrile (2) is obtained by the reaction of 1,2,3,4-tetrachloro-1,3-cyclopentadiene (1) with ethylenetetracarbonitrile by partial retro-Michael addition. The electronic and 13C NMR spectra are discussed.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198319830116
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  • 10
    Electronic Resource
    Electronic Resource
    Notiz über die Reaktion von Carbonsäurehalogeniden mit Ninhydrin (1980)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1980 (1980), S. 1919-1922 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Note on the Reaction of Acyl Halides with NinhydrinAcyl chlorides and bromides readily react with ninhydrin to give the 2-halo-1,3-dioxo-2-indanyl-carboxylates 1a-c. In the presence of small amounts of dimethylformamide, thionyl chloride reacts with ninhydrin to furnish 2,2-dichloro-1,3-indandione (2). Reaction of 1a with pyrrolidine leads to 1-oxo-2-(1-pyrrolin-1-ylio)-1H-indenolate (3).
    Notes: Carbonsäurechloride und -bromide reagieren leicht mit Ninhydrin zu den (2-Halogen-1,3-dioxo-2-indanyl)carboxylaten 1a-c. Thionylchlorid setzt sich mit Ninhydrin bei Anwesenheit kleiner Mengen Dimethylformamid zu 2,2-Dichlor-1,3-indandion (2) um. Die Reaktion von 1a mit Pyrrolidin ergibt 1-Oxo-2-(1-pyrrolin-1-ylio)-1H-inden-3-olat (3).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198019801131
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