Structural Studies of Transition Metal Complexes with 4,5-Bis(2-pyridylmethylsulfanyl)-4‘,5‘-ethylenedithiotetrathiafulvalene: Probing Their Potential for the Construction of Multifunctional Molecular Assemblies

Three divalent transition metal complexes of 4,5-bis(2-pyridylmethylsulfanyl)-4‘,5‘-ethylenedithiotetrathiafulvalene have been prepared and crystallographically characterized. The isostructural Co(II) and the Ni(II) complexes show octahedral geometries around the metal ions with the coordination sites occupied by the pyridyl nitrogen atoms and the thioether sulfur atoms of the ligand and cis coordination of the halide ions. Cyclic voltammetry reveals that the complexation leads to a small anodic shift in the first oxidation potential of the TTF system.

1,2-Bis(2-benzimidazolyl)-1,2-ethanediol, a chiral, tridentate, facially coordinating ligand

The ligand 1,2-bis(1H-benzimidazol-2-yl)-1,2-ethanediol, 1, and its methylated derivative 2 are readily synthesized from tartaric acid, and act as chiral, facially coordinating tridentate ligands, forming complexes of composition ML2 with octahedral transition metals. The copper(II) complexes show distorted 4 + 2 coordination with benzimidazoles occupying the equatorial sites and alcohol functions weakly binding in the axial sites. Nickel(II) complexes in three different states of protonation show regular octahedral geometry with the alcohols mutually cis. Deprotonation of the coordinated alcohol produces little structural change but the monodeprotonated complex forms a hydrogen bonded dimer. Magnetic measurements show the hydrogen bonded bridge to offer a pathway for weak antiferromagnetic coupling. UV-Visible spectroscopy shows the ligand to have a field intermediate between water and pyridine. The diastereoselectivity of complexation depends on the geometry: nickel(II) shows a weak preference for the homochiral complex, whereas copper(II) forms almost exclusively homochiral complexes.

Facile Synthesis of Novel Functionalized Bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) Derivatives

An improved and efficient synthetic route to four functionalized bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF) derivatives 2−5 is reported. Tetrathiolate 1 was readily prepared from 2,2‘-bis(1,3,4,6-tetrathiapentalen-5-one) under carefully controlled conditions. Subsequent reaction of 1 with selected primary alkyl halides affords new functionalized BEDT-TTF derivatives in good yields.

Insulintherapie bei Typ-2-Diabetes: ein Review vom «Wann» übers «Wie» bis zum «Warum»

Der progressive Charakter des Typ- 2-Diabetes mellitus führt in vielen Fällen nach Ausschöpfen der oralen antidiabetischen Therapie zum Einsatz von Insulin. Insulin kann aber durch- aus auch in der Frühphase direkt nach Diabetesdiagnose oder intermittierend bei Verschlechterung der glykämischen Kontrolle im Rahmen von Infekten oder Medikamenteneinnahmen (wie z.B. Kortison) hilfreich und indiziert sein. Auf jeden Fall stellt die Insulintherapie keine Einbahnstrasse dar und kann gerade in diesen Fällen durchaus auch wieder sistiert werden. Der Beginn einer Insulintherapie soll eher vorsichtig mit einer bedarfsmässigen Anpassung im Verlauf erfolgen. Diese Anpassung kann nach entsprechender Schulung durchaus auch durch den Patienten selbst erfolgen.