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  • 1
    Electronic Resource
    Electronic Resource
    Vapor pressure and evaporation coefficient of glycerol (1977)
    s.l. : American Chemical Society
    Journal of chemical & engineering data 22 (1977), S. 131-134 
    Details
    ISSN: 1520-5134
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/je60073a004
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  • 2
    Electronic Resource
    Electronic Resource
    The pseudobinary phase diagram cis-/trans-azobenzene and the cis → trans isomerization in various states of aggregation (1989)
    Springer
    Journal of thermal analysis and calorimetry 35 (1989), S. 515-526 
    Details
    ISSN: 1572-8943
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Das pseudobinäre Phasendiagramm von trans-Azobenzol und des thermisch instabilen cis-Isomeren wurde mit Hilfe thermomikroskopischer und DSC-Messungen untersucht. Es wurden zwei Eutektika bestimmt /bei 41.4 °C und 36.7 °C/, wobei das zweite Eutektikum nur in Anwesenheit einer metastabilen Modifikation von cis-Azobenzol nach Abschrecken einer Schmelze, die gleichzeitig eis- und trans-Azobenzol enthielt, vermutlich bei heterogener Keimbildung entstand. In der Schmelze und in Lösung verläuft die thermische cis-trans-Isomerisierung nach einem Geschwindigkeitsgesetz erster Ordnung. Unterhalb der eutektischen Temperatur ist die Festkörperreaktion bis zu Umsätzen von 0.20 durch dreidimensionales Keimwachstum bestimmt. Zwischen eutektischer Temperatur und Schmelzpunkt lässt sich die Reaktion durch die Gleichung von PROUT-TOMPKINS beschreiben, was auf die zunehmende Isomerisierungsgeschwindigkeit mit zunehmende Anteil Schmelze zurückzuführen ist.
    Abstract: Резюме Методой термомикрос крпии е ДСК изучена псевдобинарная фазовая диаграмма тр анс-азобензола и терм ически нестабильного цис-изомера. Определе ны две температурные эвтектики при 41,4 и 36,7°. Последняя наблюд ается только в присут ствии метастабильно го полиморфа цис-азобен зола после быстрого охлаждения расплава, содержащег о как цис-, так и транс-азобензол, в образующегося, веро ятно, в условиях гетер огенного образования центров кристаллиза ции. В расплаве в в раст воре термически наведенная цис-тране изомеризация подчин яется реакции первого порядка. Ниже температуры эвтекти ки скорость реакции контролируется трех размерным ростом зар одышей кристаллов со степенью превращени я равной 0,20. В интервале между температурой эвтектики и точками п лавления реакция сле дует кинетике, подчиняющейся закон у Праут-Томпкинса. Это является причиной увеличения скорости изомеризации с увели чением доли расплава.
    Notes: Abstract The pseudobinary phase diagram of trans-azobenzene and the thermally instable cis-isomer was examined by thermomicroscopical and DSC-measurements. Two eutectic temperatures have been determined (at 41.4 C and 36.7 C). The latter occurs only in the presence of a metastable polymorph of cis-azobenzene after quenching a melt, that contained as well cis-as trans-azobenzene, presumable under conditions of heterogeneous nucleation. In the melt and in solution the thermally induced cis-trans-isomerization follows first order kinetics. Below the eutectic temperature the rate is controlled by three-dimensional nuclei growth to reaction extent 0.20. Between the eutectic temperature and the melting points of product respectively educt the kinetics follow the PROUT-TOMPKINS law. The reason is the increasing isomerization rate with increasing fraction of melt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01904453
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  • 3
    Electronic Resource
    Electronic Resource
    Ester von (Hydroxymethyl)diorganylsilanen: Synthese und thermisch induzierte Umlagerung (1992)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 591-605 
    Details
    ISSN: 0009-2940
    Keywords: (Hydroxymethyl)diorganylsilanes, esters of ; Rearrangement, thermally induced ; Kinetics ; DSC ; Calculations, ab initio ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Esters of (Hydroxymethyl)diorganylsilanes: Synthesis and Thermally Induced RearrangementTwenty silanes of the type R1R2Si(H)CH2OR3 (A) were synthesized [R1, R2 = Me, Ph, 1-naphthyl, PhCH2,Me3SiCH2; OR3 = OC(O)Me, OC(O)Ph, OC(O)CF3, OS(O)2CF3, OP(O)Ph2, OC(O)Cl] and studied for their thermal behaviour. The silanes A undergo a thermally induced rearrangement to give the corresponding silanes R1R2Si(OR3)Me (B). For compounds with OR3 = OC(O)Cl, an additional decarboxylation takes place to yield the chlorosilanes R1R2Si(Cl)Me. Except for the derivatives with OR3 = OC(O)Cl, the energetic (reaction enthalpy) and kinetic data (reaction order, frequency factor, enthalpy and entropy of activation) of these reactions were studied by means of differential scanning calorimetry (DSC). In addition, the kinetics of all reactions were investigated by 1H-NMR spectroscopy. The transition state of the rearrangement was investigated by an ab initio study based on the model compound H3SiCH2OC(O)H [→ MeH2SiOC(O)H]. The theoretical data and the experimentally obtained energetic and kinetic data are discussed in terms of mechanistic aspects of the rearrangement reaction A → B.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19921250310
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  • 4
    Electronic Resource
    Electronic Resource
    Sila-Pharmaka, 371) Darstellung und Eigenschaften der Enantiomere der Antimuskarinika Sila-Procyclidin und Sila-Tricyclamol-iodid: Optisch aktive Silanole mit Silicium als Chiralitätszentrum2) (1987)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 1229-1237 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sila-Pharmaca, 371). - Preparation and Properties of tbe Enantiomers of the Antimuscarinic Agents Sila-Procyclidine and Sila-Tricyclamol Iodide: optically Active Silanols with Silicon as the Centre of Chirality2)The enantiomers of sila-procyclidine (R)-1b and (S)-1b [ 〉 97% ee (NMR), 99.7% ee (DSC)] were obtained by resolution with L-(+)- and D-(-)-tartaric acid, respectively. Starting from (R)-1b and (S)-1b, the hydrochlorides (R)-2b and (S)-2b were prepared and the enantiomers of sila-tricyclamol iodide (R)-3b and (S)-3b [ 〉 96% ee (NMR)] were synthesized by reaction with CH3I. The optically active silanols show configurational stability in the crystalline state and in inert solvents, whereas they racemize in aqueous solution (3b faster than 1b). By analogy with the stereoselectivity of antimuscarinic action of the enantiomers of the carbon analogues procyclidine (1a) and tricyclamol iodide (3a), the (R) enantiomers of 1b and 3b show a greater affinity for the ileal M2β and atrial M2α muscarinic receptors of the guinea pig than the corresponding (S) antipodes. All silicon compounds exhibit a greater antimuscarinic potency than their carbon analogues, whereas the stereoselectivity of action is more pronounced for the carbon compounds. The differences in affinity for (R)-1b and (S)-1b for ileal and atrial muscarinic receptors confirm the present concept of heterogeneity in muscarinic M2 receptors (M2α: atrial type; M2β: ileal type).
    Notes: Durch Racematspaltung mit L-(+)- bzw. D-(-)-Weinsäure wurden die Enantiomere des Sila-Procyclidins (R)-1b und (S)-1b erhalten [〉 97% ee (NMR), 99.7% ee (DSC)]. Daraus wurden die Hydrochloride (R)-2b und (S)-2b und durch Umsetzung mit CH3I die Enantiomere des Sila-Tricyclamol-iodids (R)-3b und (S)-3b [ 〉 96% ee (NMR)] hergestellt. Die optisch aktiven Silanole sind in kristalliner Form und in inerten Lösungsmitteln konfigurationsstabil, während sie in wässeriger Lösung racemisieren (3b schneller als 1b). In Analogie zur Stereoselektivität der antimuskarinischen Wirkung der Enantiomere der Kohlenstoff-Analoga Procyclidin (1a) und Tricyclamol-iodid (3a) besitzen die (R)-Enantiomere von 1b und 3b eine größere Affinität zu den ilealen M2β- und atrialen M2α- Muskarinrezeptoren des Meerschweinchens als die (S)-Antipoden. Alle Silicium-Verbindungen sind stärker antimuskarinisch wirksam als ihre Kohlenstoff-Analoga, deren Stereoselektivität jedoch stärker ausgeprägt ist. Die Unterschiede in der Affinität von (R)-1b und (S)-1b zu den ilealen und atrialen Muskarinrezeptoren bestätigen das Konzept der Heterogenität muskarinischer M2-Rezeptoren (M2α: atrialer Typ; M2β: ilealer Typ).
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19871200719
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  • 5
    Electronic Resource
    Electronic Resource
    Polysulfonylamines. LXVII. Heat of Hydrolysis of N-Acetyl Dimesylamine (N,N-dimesyl acetamide) (1995)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 337 (1995), S. 413-415 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19953370188
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  • 6
    Electronic Resource
    Electronic Resource
    Wärmetransportmechanismus in der Nähe ruhender verdampfender bzw. verdunstender Wasseroberflächen (1987)
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 59 (1987), S. 430-431 
    Details
    ISSN: 0009-286X
    Keywords: Wärmetransport ; Mechanismus ; Wasser ; Verdampfung ; Verdunstung ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cite.330590518
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  • 7
    Electronic Resource
    Electronic Resource
    Darstellung und Eigenschaften der Enantiomere des selektiven Antimuscarinikums 1-Cyclohexyl-1-phenyl-4-piperidino-1-butanol (Hexahydro-Difenidol) (1989)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1989 (1989), S. 137-143 
    Details
    ISSN: 0170-2041
    Keywords: Difenidol, (R)- and (S)-hexahydro- ; Antimuscarinic properties ; Muscarinic receptor subtypes ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Properties of the Enantiomers of the Selective Antimuscarinic Agent 1-Cyclohexyl-1-phenyl-4-piperidino-1-butanol (Hexahydro-Difenidol)Using (S)- or (R)-mandelic acid as the resolving agent, the enantiomers of 1-cyclohexyl-1-phenyl-4-piperidino-2-butin-1-ol [(R)-2 and (S)-2] were prepared (enantiomeric purity: ee = 99.7%; calorimetric analysis). Catalytic hydrogenation (Pd/C contact) of (R)-2 and (S)-2 yielded the enantiomers of 1-cyclohexyl-1-phenyl-4-piperidino-1-butanol [(R)- and (S)-hexahydro-difenidol, (R)-1a and (S)-1a] which were isolated as hydrochlorides [(R)-1a ⋅ HCl and (S)-1a ⋅ HCl, ee = 99.7%]. The absolute configuration of the enantiomers of 1a and 2 was determined by an X-ray crystal structure analysis of the mandelate (S)-1a ⋅ (R)-C6H5CH(OH)COOH. (R)-Hexahydro-difenidol [(R)-1a] and (R)-2 exhibit a higher affinity for the atrial M2α and ileal M2β muscarinic receptors of the guinea pig than the respective antipodes (S)-1a and (S)-2 (atrial stereoselectivity index: 17 and 8.6, respectively; ileal stereoselectivity index: 193 and 44, respectively). In addition, (R)-1a and (R)-2 exhibit a significantly higher affinity for the M2β receptors of the ileum than for the M2α receptors of the atrium (atrium/ileum ratio: 21 and 10, respectively). Thus, (R)-1a and (R)-2 are valuable tools for the identification and characterization of muscarinic M2 subtypes. In contrast, the less potent (S)-enantiomers of 1a and 2 do not differentiate between M2α and M2β receptors.
    Notes: Durch Racematspaltung mit (S)- bzw. (R)-Mandelsäure wurden die Enantiomere von 1-Cyclohexyl-1-phenyl-4-piperidino-2-butin-1-ol [(R)-2 und (S)-2] dargestellt (Enantiomerenreinheit: ee = 99.7%, kalorimetrische Analyse). Katalytische Hydrierung (Pd/C-Kontakt) von (R)-2 und (S)-2 ergab die Enantiomere von 1-Cyclohexyl-1-phenyl-4-piperidino-1-butanol [(R)- und (S)-Hexahydro-Difenidol, (R)-1a und (S)-1a], die als Hydrochloride (R)-1a ⋅ HCl und (S)-1a ⋅ HCl isoliert wurden (ee = 99.7%). Die absolute Konfiguration der Enantiomere von 1a und 2 wurde durch Röntgenkristallstrukturanalyse des Mandelats (S)-1a ⋅ (R)-C6H5CH(OH)COOH bestimmt. (R)-Hexahydro-Difenidol [(R)-1a] und (R)-2 besitzen eine höhere Affinität zu den atrialen M2α-und ilealen M2β-Muscarinrezeptoren des Meerschweinchens als die entsprechenden Antipoden (S)-1a und (S)-2 (atrialer Stereoselektivitätsindex: 17 bzw. 8.6; ilealer Stereoselektivitätsindex: 193 bzw. 44). Darüber hinaus besitzen (R)-1a und (R)-2 eine signifikant höhere Affinität zu den M2β-Rezeptoren des Ileums als zu den M2α-Rezeptoren des Atriums und sind somit wertvolle Modellverbindungen zur Identifizierung und Charakterisierung von muscarinischen M2-Subtypen (Atrium/Ileum-Quotient: 21 bzw. 10). Im Gegensatz hierzu vermögen die schwächer wirksamen (S)-Enantiomere von 1a und 2 nicht zwischen den M2α- und M2β-Rezeptoren zu unterscheiden.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198919890128
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  • 8
    Electronic Resource
    Electronic Resource
    Enantiomers of the muscarinic antagonist 1-cyclohexyl-1-(4-fluorophenyl)-4-piperidino-1-butanol (p-fluoro-hexahydro-difenidol): Synthesis, absolute configuration, and enantiomeric purity (1991)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1991 (1991), S. 523-527 
    Details
    ISSN: 0170-2041
    Keywords: Difenidol, p-fluoro-hexahydro-, enantiomers of ; Muscarinic receptors, subtypes of ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The enantiomers of the antimuscarinic agent 1-cyclohexyl-1-(4-fluorophenyl)-4-piperidino-1-butanol [(R)- and (S)-p-fluorohexahydro-difenidol] [(R)- and (S)-2a] and their methiodides (R)-3 and (S)-3 were prepared with high enantiomeric purity. (R)-2a and (S)-2a (isolated as hydrochlorides) were obtained by catalytic hydrogenation (Pd/C contact) of the corresponding enantiomers of 1-cyclohexyl-1-(4-fluorophenyl)-4-piperidino-2-butyn-1-ol [(R)- and (S)-4]. Reaction of (R)-2a and (S)-2a with methyl iodide led to (R)-3 and (S)-3, respectively. The unsaturated precursors (R)- and (S)-4 (enantiomeric purity ≥99.80 and ≥99.94% e.e.; calorimetric analysis) were prepared by resolution of rac-4 [available from 4-FC6H4C(O)C6H11 by reaction with LiC≡CCH2NC5H10] using (R)- and (S)-mandelic acid as resolving agents. The absolute configurations of the (R) and (S) enantiomers of 2a, 3, and 4 were determined by an X-ray crystal-structure analysis of (S)-5, the methiodide of (S)-4. (R)-2a and (R)-3 exhibit a higher affinity for muscarinic M1, M2, M3, and M4 receptors (by up to two orders of magnitude) than their corresponding antipodes (S)-2a and (S)-3, the degree of stereoselectivity depending on the receptor subtype involved. (R)-2a represents a useful tool for muscarinic receptor research (affinity profile: M1 ≈ M3 ≈ M4 〉 M2).
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.199119910196
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  • 9
    Electronic Resource
    Electronic Resource
    Determination of Thermodynamic Properties. 2. Auflage. (Reihe: Physical Methods of Chemistry, Vol. 6.) Herausgegeben von B. W. Rossiter und R. C. Baetzold. Wiley, Chichester, 1992. XI, 743 S., geb. 157.00 £. - ISBN 0-471-57087-7 (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 106 (1994), S. 730-731 
    Details
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ange.19941060638
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  • 10
    Electronic Resource
    Electronic Resource
    Thermal Analysis  -  Techniques and Applications. Herausgegeben von E. L. Charsley und S. B. Warrington. The Royal Society of Chemistry, Cambridge, 1992 (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 106 (1994), S. 502-502 
    Details
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ange.19941060439
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