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  • 1
    Electronic Resource
    Electronic Resource
    Säurestärke und Komplexbildung von Curcuminoiden (1988)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 111-118 
    Details
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Acidity and Complex Formation of CurcuminoidsThe stoichiometric acid dissociation constants of curcumin 1a and derivatives as well as the stoichiometric stability constants of the Cu(II)- and Ni(II)-complexes of these substances have been determined by pH-potentiometric titrations in dioxane-water mixture.The influence of different substituents on the pKa-values and the stability constants is discussed. The complexing properties of the —CO—CH2—CO— structural element of the ligands are not significantly changed when the phenyl group is substituted by the styryl group. Solid CuL2-complexes have been characterized. The coordination of the ester group in the tricarbonyl ligand systems 4 was excluded by i.r. spectroscopy.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19883300120
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  • 2
    Electronic Resource
    Electronic Resource
    Ligand Properties of N-Acyl-thiocarbamic-O-alkylesters - A new class of aza-analogous 1,3-thioxoketones (1995)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 337 (1995), S. 184-188 
    Details
    ISSN: 0941-1216
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of six N-benzoyl-thiocarbamic-O-alkylesters (R=Me, Et, i-Pr, Benzyl, n-Hex, n-Dodec; 1-6) has been prepared and characterized. They are weak monoprotic acids. The compounds behave as fairly stable and versatile bidentate (O,S)-chelating ligands towards multivalent metal ions e. g. Ni(II), Cu(II), Pb(II) the stability constants of which have been determined in 75 vol% dioxane/water. The molecular structure of bis(O-ethyl-N-benzoylthiocarbamato)nickel(II) 2a is presented. The coordination of the nickel atom is square planar with the two sulphur atoms in cis position.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19953370141
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  • 3
    Electronic Resource
    Electronic Resource
    Zur Reaktion von N-(N′,N′-Dialkyl(aryl)amino-thiocarbonyl)benzimidoylchloriden mit Kaliumthiocyanat (1988)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 330 (1988), S. 241-247 
    Details
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions of N-(N′,N′-Dialkyl(aryl)amino-thiocarbonyl)benzimidoylchlorides with Potassium ThiocyanateThe treatment of the title compound N-(amino-thiocarbonyl)-benzimidoylchloride 1 with potassium thiocyanate leads in dependence on the solvents (methanol, acetic acid, acetone) either to the 1,3,5-thiadiazine-2-thione 2a-d or to the ring opened isothiocyanate 4a, b. In the case of methanol the N-(amino-thiocarbonyl)benzimidates were formed as by-products.The structure of the products is confirmed by analytical data and by chemical transformations. 2a reacts with methyl iodide to form the 2-methylthio-6-morpholino-4-phenyl-1,3,5-thiadiaziniumiodide 3a. From 4a and water the N-(morpholino-thiocarbonyl)benzamide 5a arises. The reaction of morpholine with 4a yields the benzamidine 6a.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19883300210
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  • 4
    Electronic Resource
    Electronic Resource
    Dithiazoliumsalze mit Halometallaten - Synthese und Struktur von 3-Diethylamino-5-phenyl-1,2,4-dithiazolium-tetrachloro-niccolat(II)Professor Lothar Kolditz zum 60. Geburtstage gewidmet (1989)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 576 (1989), S. 203-214 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Dithiazolium Salts of Halometalates - Synthesis and Structure of 3-Diethylamino-5-phenyl-1,2,4-dithiazolium-tetrachloroniccolate (II)Chlorination of NiII-coordinated 1,1-diethyl-3-benzoyl-thiourea by SOCl2 in acetonitrile yields turquoise 3-diethyl-amino-5-phenyl-1,2,4-dithiazolium-tetrachloroniccolate. Its reduction produces cis-bis-(1,1-diethyl-3-thiobenzoylthioureato)nickel(II). The mechanism of formation as well as the crystal and molecular structure of the title compound are presented.
    Notes: Die Chlorierung von an NiII innerkomplex gebundenem 1,1-Diethyl-3-benzoylthioharnstoff mittels SOCl2 führt in Acetonitril zu türkisem 3-Diethylamino-5-phenyl-1,2,4-dithiazolium-tetrachloroniccolat, aus dem durch Reduktion cis-Bis-(1,1-diethyl-3-thiobenzoyl-thioureato)nickel(II) zugänglich ist. Der Bildungsmechanismus des Dithiazoliumsalzes wird erörtert und die Kristall- und Molekülstrukturanalyse vorgestellt.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19895760123
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  • 5
    Electronic Resource
    Electronic Resource
    Kristall- und Molekülstruktur eines neuartigen Trimetallamacrocyclus: cyclo-Tri[nickel-μ-[1,1,1′,1′-tetraethyl-3,3′-terephthaloyl-bis-thioureato(2-)-S,O:O′,S′]] (1989)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 578 (1989), S. 191-197 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal and Molecular Structure of a Novel Trimetallamacrocyle: cyclo-Tri[nickel-μ-[1,1,1′,1′-tetraethyl-3,3′-terephthaloyl-bis-thioureato(2-)-S,O:O′,S′]]The structure of the title compound has been determined by an X-ray structure analysis. The compound crystallizes in the triclinic space group P1 with a = 13.900, b = 15.403, c = 16.615 Å, δ = 84.01, β = 70.61, γ = 89.64° and Z = 2. The solution of the structure was performed by direct methods. The final R value was R = 0.073 for 2824 observed reflections. The molecule has a cyclic structure consisting of three molecules of the quadridentate ligand and three nickel atoms. The formed ring is a 27-membered trimetallamacrocycle. The nickel atoms form a nearly equilateral triangle with distances of 10.25 Å, 10.45 Å and 10.45 Å. The molecule is relatively planar.
    Notes: Die Struktur der Titelverbindung wurde durch Röntgenkristallstrukturanalyse bestimmt. Die Verbindung kristallisiert triklin in der Raumgruppe P1 mit den Gitterkonstanten a = 13,900, b = 15,403, c = 16,615 Å, δ = 84,01, β = 70,61, γ = 89,64° und Z = 2. Die Lösung der Struktur erfolgte mit direkten Methoden. Der abschließende R-Wert betrug R = 0,073 für 2284 beobachtete Reflexe. Das Molekül besitzt eine zyklische Struktur, bestehend aus drei Molekülen des quadridentaten Liganden und drei Nickel-Atomen. Der gebildete Ring ist ein 27gliedriger Trimetallamacrocyclus. Die Nickel-Atome bilden ein nahezu gleichseitiges Dreieck mit Abständen von 10,25 Å, 10,45 Å und 10,45 Å. Das Molekül ist relativ planar.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19895780122
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  • 6
    Electronic Resource
    Electronic Resource
    Die Chelatbildung von N-Tris(2-aminoethyl)amin-N′,N′,N″,N″,N‴,N‴-hexaessigsäure (H6TTAHA) und N-(Pyrid-2-yl-methyl)ethylendiamin-N,N′,N′-triessigsäure (H3PEDTA) mit Gadolinium(III) - Synthesen, Komplexstabilität und NMR-RelaxivitätProfessor Egon Uhlig zum 65. Geburtstag gewidmet (1995)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 807-811 
    Details
    ISSN: 0044-2313
    Keywords: Chelates, Gadolinium(III) ; Stability Constants ; 1H-NMR Relaxivity ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chelate Formation of N-Tris(2-aminoethyl)amine-N′,N′,N″,N″,N‴,N‴-hexaacetic Acid (H6TTAHA) and N-(Pyrid-2-yl-methyl)ethylenediamine-N,N′,N′-triacetic Acid (H3PEDTA) with Gadolinium(III) - Syntheses, Stability Constants, and NMR-RelaxivitiesThe chelate formation of N-tris(2-aminoethyl)amine-N′,N′,N″,N″,N‴,N‴-hexaacetic acid (H6TTAHA) and N-(pyrid-2-yl-methyl)ethylenediamine-N,N′,N′-triacetic acid (H3PEDTA) with gadolinium(III) has been studied potentiometrically in aqueous solution at 25°C and μ = 0.1 (KCl). [Gd(TTAHA)]3-: 1gβM/ML = 19.0; {H[Gd(TTAHA)]}2-: 1gKH/MHL = 8.30; [Gd(PEDTA)]: 1gβM/ML = 15.56. Both 1 : 1 gadolinium(III) complexes were isolated as Na2H[Gd(C18H24N4O12)] · 3.5 H2O and [Gd(C14H16N3O6)] · 3 H2O, respectively. Their 1H-NMR relaxivities [1 · mmol-1 · s-1] ({H[Gd(TTAHA)]}2-: 9.5; [Gd(PEDTA)]: 8.8) offer promising applications for 1H-NMR imaging.
    Notes: Die Komplexbildung von N-Tris(2-aminoethyl)amin-N′,N′,N″,N″,N‴,N‴-hexaessigsäure (H6TTAHA) und N-(Pyrid-2-yl-methyl)ethylendiamin-N,N′,N′-triessigsäure (H3PEDTA) mit Gadolinium(III) wurde in wässeriger Lösung bei 25°C und μ = 0,1 (KCl) potentiometrisch untersucht. [Gd(TTAHA)]3-: 1gβM/ML = 19,0; {H[Gd(TTAHA)]}2-: 1gKH/MHL = 8,30; [Gd(PEDTA)]: 1gβM/ML = 15,56. Die 1 : 1-Gadolinium(III)-Komplexe wurden im Fall der H6TTAHA als Dinatriumsalz Na2H[Gd(C18H24N4O12)] · 3,5 H2O, bei der H3PEDTA als Neutralkomplex [Gd(C14H16N3O6)] · 3 H2O erhalten. Ihre NMR-Protonenrelaxivitäten [1 · mmol-1 · s-1] ({H[Gd(TTAHA)]}2-; 9,5; [Gd(PEDTA)]: 8,8) eröffnen Anwendungen als Kontrastmittel für die Kernspintomographie.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19956210518
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  • 7
    Electronic Resource
    Electronic Resource
    N,N-Dialkylierte N′-Ferrocenoylthioharnstoffe und Ferrocen-1,1′-dicarbonsäure-di-N,N-dialkyl-thioureide als Liganden für Übergangsmetalle: Darstellung, pH-potentiometrische, röntgenkristallstrukturanalytische und EPR-EinkristalluntersuchungenProfessor Eberhard Hoyer zum 65. Geburtstag gewidmet (1996)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 692-700 
    Details
    ISSN: 0044-2313
    Keywords: Ferrocene ; Thioureas ; Chelates ; X-Ray Structure ; EPR-Single Crystal ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: N,N-Dialkyl-N′-ferrocenoylthioureas and Ferrocene-1,1′ -dicarbonic-acid-di-N,N-dialkylthioureides as Ligands for Transition Metals: Synthesis, Acid-Dissociation Constants, X-Ray Structure Determination, and EPR-Single Crystal InvestigationReaction of ferrocenoylisothiocyanate or ferrocene-1,1′ -dicarbonic acid -diisothiocyanate with secondary amines gives N,N-dialkyl-N′ -ferrocenoylthioureas or the respective ferrocene-1,1′-dicarbonic acid-di-N,N-dialkyl-thioureides. The former yield neutral complexes with transition metal ions (Ni2+, Cu2+, Co3+, Pt2+, Fe3+). The acid dissociation constants of the ligands were determined. The EPR spectra of a bis-(N,N-dinbutyl-N′-ferrocenoylthioureato)copper(II) single crystal are discussed. The X-ray structure determination of ferrocene-1,1′-dicarbonic acid-di-N,N-diethyl-thioureide and its different behaviour against Ni2+ and Cu2+ is presented.
    Notes: Die Reaktion von Ferrocenoylisothiocyanat bzw. Ferrocen-1,1′-dicarbonsäure-diisothiocyanat mit sekundären Aminen führt zu den entsprechenden N,N-dialkylierten N′-Ferrocenoylthioharnstoffen bzw. zu Ferrocen-1,1′-dicarbonsäure-di-N,N-dialkyl-thioureiden. Erstere bilden mit Übergangsmetallionen (Ni2+, Cu2+, Co3+, Pt2+, Fe3+) Neutralkomplexe. Die Säuredissoziationskonstanten der Liganden werden angegeben. Eine Einkristall-EPR-Untersuchung des Bis-(N,N-dinbutyl-N′ -ferrocenoylthioureato)kupfer(II) wird diskutiert. Die Röntgenkristallstrukturanalyse von Ferrocen-1,1′-dicarbonsäure-di-N,N-diethyl-thioureid und dessen unterschiedliches Verhalten gegenüber Ni2+ und Cu2+ werden erörtert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19966220421
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  • 8
    Electronic Resource
    Electronic Resource
    Molekülstrukturen von Kupfer(II)- und Eisen(III)-Chlorokomplexen mit di- und monoprotoniertem N-(Pyrid-2-ylmethyl)ethylendiamin-N,N′,N′-triacetat (H2pedta-; Hpedta2-)Professor Eberhard Hoyer zum 65. Geburtstag gewidmet (1996)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 707-712 
    Details
    ISSN: 0044-2313
    Keywords: Copper(II) chelate complex ; iron(III) chelate complex ; edta-type ligands ; chelates ; X-ray structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Molecular Structures of Copper(II) and Iron(III) Chloro Complexes with di- and monoprotonated N-(pyrid-2-ylmethyl)ethylenediamine-N,N′,N′-triacetate (H2pedta-; Hpedta2-)The molecular structures of two complexes of di- and monoprotonated N-(pyrid-2-ylmethyl)ethylenediamine-N,N′,N′ -triacetate (pedta3-) with CuII and FeIII as central atoms have been determined by single crystal X-ray diffraction methods. Both complexes have a distorted octahedral coordination with H2pedta- and Hpedta2- as pentadentate ligands and a chloride ion occupying the sixth coordination site. The different oxidation states of the central atoms result in a completely different coordination behaviour of the carboxyl groups. In both complexes one of the —CH2—COOH groups is uncoordinated. In the FeIII complex, the central atom is coordinated by the hydroxylic O atoms of the deprotonated carboxyl groups. Contrary to this in the CuII complex, the central atom is coordinated by the carbonylic O atoms. One of the coordinated carboxyl groups is protonated and the other is deprotonated. All protonated carboxyl groups in both complexes form intermolecular hydrogen bonds.
    Notes: Die Molekülstrukturen zweier Komplexe von di- bzw. monoprotoniertem N-(Pyrid-2-ylmethyl)ethylendiamin-N,N′,N′-triacetat (pedta3-) mit CuII bzw. FeIII als Zentralatome wurden durch Röntgenkristallstrukturanalyse bestimmt. Beide Komplexe haben eine verzerrt oktaedrische Koordination, in der H2pedta- bzw. Hpedta2- als fünfzähnige Liganden wirken. Die sechste Koordinationsstelle wird durch ein Chlorid-Ion besetzt. Die unterschiedliche Oxidationsstufe der Zentralatome führt zu einem unterschiedlichen Koordinationsverhalten der Carboxylgruppen. In beiden Komplexen ist eine der —CH2—COOH-Gruppen unkoordiniert. Im FeIII-Komplex erfolgt die Koordination über die hydroxylischen O-Atome der deprotonierten Carboxylgruppen. Im Gegensatz dazu beobachtet man im CuII-Komplex Koordination über die carbonylischen O-Atome, wobei eine der beiden Carboxylgruppen protoniert und die andere deprotoniert vorliegt. Von allen protonierten Carboxylgruppen in beiden Komplexen gehen intermolekulare Wasserstoffbrückenbindungen aus.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19966220423
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  • 9
    Electronic Resource
    Electronic Resource
    Zweikernverbrückende Bis-N-acylthioharnstoffe-Liganden in Trimetallamacrocyclen und Chelatpolymeren (1986)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 537 (1986), S. 133-144 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Binucleating Bis-N-acylthioureas - Ligands in Trimetallamacrocycles and Polynuclear Metal ChelatesBy symmetric linking of two bidentate N-acylthioureas two types of quadridentate bis-N-acylthioureas are available which act - after di-deprotonation - as bis-bidentate S, O ligands towards polyvalent metal ions. They can form oligomeric or polymeric, cyclic or chain chelates. With 1,1,1′,1′-tetraalkyl-3,3′-terephthaloyl-bis-thioureas (H2L) we obtained oligomeric triangulotrimetalla macrocycles Ni3L3 and Cu3L3. They contain perimetric 27-membered rings, counting the internal oxygens, or 39-membered rings with the external sulfur atoms on the other hand, i. e. equal chalcogen atoms are in cis-positions within each chelate unit around the three metal ions. The trimetallamacrocyclic structure was proved by x-ray crystal and molecular structure analysis of Ni3L3 (alkyl = Et) or EPR of the corresponding Cu3L3. Diamin-linked bis-N-acylthioureas form insoluble 1:1 polymeric chelates.
    Notes: Durch geeignete symmetrische Verknüpfung zweier bidentater N-Acylthioharnstoffunktionen sind zwei Typen quadridentater Bis-N-acylthioharnstoffe zugänglich, die gegenüber mehrwertigen Metallionen als bis-bidentate S, O-Liganden fungieren. Sie können oligomere oder polymere, zyklische oder offenkettige Chelate bilden. Mit 1,1,1′,1′-Tetraalkyl-3,3′-terephthaloyl-bis-thioharnstoffen (H2L) erhielten wir oligomere triangulare Trimetallamacrocyclen Ni3L3 und Cu3L3, die perimetrische 27-Ringe mit den internen Sauerstoffligatoren bzw. 39-Ringe mit den externen Schwefelligatoren aufweisen. In jeder Chelateinheit sind die Schwefel- bzw. Sauerstoffatome in cis-Anordnung. Die makrozyklische Struktur wurde mittels RKSA (Ni3L3; Alkyl = Et) bzw. EPR (Cu3L3; Alkyl = Et) bewiesen. Diaminverknüpfte Bis-N-acylthioharnstoffe bilden unlösliche 1:1 Polymerchelate.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19865370614
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  • 10
    Electronic Resource
    Electronic Resource
    Schwermetallchelate von α-Cyano-β-amino-dithioacrylsäureestern (1986)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 543 (1986), S. 186-191 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heavy Metal Chelates of α-Cyano-β-amino-dithioacrylatesThe inner metal chelates of PdII, NiII, CoIII, and AgI with α-cyano-β-amino-dithioacrylates have been prepared. The coordination of the dithioester group and the amine nitrogen (S/N-coordination) has been proved by the chemical shift of the S2p and N1s electron binding energies in the ESCA spectra.
    Notes: Es wurden Innerchelatmetallkomplexe des PdII, NiII, CuII, CoIII und AgI mit α-Cyano-β-amino-dithioacrylsäureestern dargestellt. Die Koordination der Dithiocarbonester-gruppierung und des Aminstickstoffs (S/N-Koordination) wird durch die chemische Verschiebung der S2p- und N1s-Elektronenbindungsenergien in den ESCA-Spektren bewiesen.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19865431222
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