Zur Komplexbildung von N‐(Thiocarbamoyl)benzamidinen

Abstract

N‐(Thiocarbamoyl)banzamidine 1 und N‐(Thiocarbamoyl)‐N′‐phenyl‐benzamidine 2 bilden mit Ni2+‐, Pd2+‐, Co3+‐ und Ag+‐Ionen in alkoholischer Lösung kristalline Innerchelatkomplexe1ah und 2ah mit N/S‐Koordination. Aus ESCA‐Spektren wird im Falle der Chelate von 1 als Haftgruppe NH nachgewiesen und ihre höhere Donorfähigkeit im Vergleich mit dem isosterne Sauerstoffhaftatom gegenüber Nickel fest‐gestellt. Dies wird durch d‐1H‐NMR‐spektroskopisch bestimmte Werte von ΔGc≠ für die behinderte Rotation der Et2N‐Gruppe an 1 a unterstützt.

Syntheses, Structures, and Biological Activity of NiII, PdII, and PtII Complexes with New Tetradentate Benzamidine Ligands

“…Despite the fact that bidentate N-(dialkylthiocarbamoyl)-benzamidines (1) (Scheme 1) are well known chelators, which form stable complexes with most transition metal ions, [1][2][3][4] the coordination chemistry of tri-and tetradentate benzamidines is almost unexplored. [5][6][7][8] Hitherto, only a few tridentate benzamidines, [5][6][7][8] and two tetradentate benzamidines with an S,N,N,S donor set have been reported.…”

Aqueous solubilities of five N-(diethylaminothiocarbonyl)benzimido derivatives at T = 298.15 K

“…While pK values of a variety of structural analogues were successfully measured by pH potentiometry before, no data for the title compounds could be obtained (Hartung et al, 1985;Mühl et al, 1986). Hence, at this stage, we assume neutral species being predominant in aqueous solutions at environmentally relevant medium pH ranges.…”

“…They are accessible through the reaction of coordinated N-Acylthiourea with acid chlorides, followed by further derivatisation. Members of this family are known chelating agents (Hartung et al, 1985), with potential applications e.g., radio pharmaceuticals ( 99m Tc) (Abram et al, 1989). A large number of serine proteinase inhibitors has been developed, starting from benzamidine and its derivatives (Ensinck et al, 1972;Henkel et al, 1983;Jeffcoate and White, 1974).…”

Synthesis and Characterization of Unusual Oxidorhenium(V) Cores

“…This has also been observed for reactions with dialkylaminothiocarbonylbenzamidines, the ligands under study in this report. [6] Despite the fact that numerous bidentate dialkylaminothiocarbonylbenzamidines have been synthesized and their coordination chemistry is well explored, [7] tridentate representatives of this ligand class are rare and first reports about their coordination behavior with rhenium and technetium cores were only recently published. [8][9][10][11][12] Some of the new rhenium compounds show promising cytotoxic effects against breast cancer cells, [12] whereas an extension of the ligand backbone may give access to multidentate ligand systems with the potential for bioconjugation.…”