The design and synthesis of glycol-functionalized porphyrins that contain one to four low molecular weight glycol chains that are linked via ether bonds to the meta-phenyl positions of meso-tetraphenylporphyrin and the comparison of fluorinated and nonfluorinated para derivatives are reported. The cellular uptake and photodynamic activity significantly depend on terminal groups of the glycol substituent. Hydroxy glycol porphyrins, in contrast with methoxy glycol porphyrins, show efficient intracellular transport and a high induction of apoptosis in tumor cell lines in vitro . Furthermore, the ethylene glycol chain at the meta position exhibits a superior efficacy that leads to the permanent ablation of human breast carcinoma (MDA-MB-231) in nude mice. In addition, fluorination enhanced the photosensitizing potential of para-phenyl derivatives. The analysis of the cell-death mechanism revealed that glycol-functionalized porphyrins represent novel nonmitochondrially localized photosensitizers that have a profound ability to induce apoptosis in tumor cells that act upstream of caspase activation. The strong interaction with a tumor marker (sialic acid) indicates the preferential association of these compounds with tumor cells.

Different bridging geometries can explain the observation that porphyrin molecules with added thiol end groups and pyridine axial groups form more‐stable single‐molecule junctions with an increased spread in low‐bias conductance. The stability of these geometries is demonstrated by time‐dependent conductance measurements. In contrast, rodlike molecules show one preferential binding geometry.

The porphyrin-cyclodextrin conjugates were prepared and tested for selective and effective multifunctional drug delivery and therapy. The porphyrin receptor system combines efficient binding of the selected drug to the cyclodextrin cavity and photosensitizing properties of the porphyrin moiety with high accumulation of the whole complex in cancer tissue. The combined effect of chemotherapy and photodynamic therapy is demonstrated by in vitro and in vivo studies.

Unterschiedliche Brückengeometrien können die Beobachtung erklären, dass Porphyrinmoleküle mit Thiolendgruppen und axialen Pyridingruppen stabilere Einzelmolekülkontakte mit einer größeren Spanne der Ruheleitfähigkeit bilden. Die Stabilität dieser Geometrien wurde in zeitabhängigen Leitfähigkeitsmessungen gezeigt. Stäbchenförmige Moleküle dagegen haben eine bevorzugte Bindungsgeometrie.

The rational design of molecules with selective intracellular targeting is a great challenge for contemporary chemistry and life sciences. Here, we demonstrate a rational approach to development of compartment-specific fluorescent dyes from the γ-aryl substituted pentamethine family. These novel dyes exhibit an extraordinary affinity and selectivity for cardiolipin in inner mitochondrial membrane and possess excellent photostability, fluorescent properties, and low phototoxicity. Selective imaging of live and fixed mitochondria was achieved in various cell lines using nanomolar concentrations of these dyes. Their high localization specificity and low toxicity enables study of morphological changes, structural complexity, and dynamics of mitochondria playing a pivotal role in many pathological diseases. These far-red emitting dyes could also serve in a variety of biomedical applications.

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Fluorinated building blocks, 2-(perfluorohexyl)ethyl triflate (11a) and 2-(perfluorooctyl)ethyl triflate (11b) were prepared from the corresponding fluoroalkanols and triflic anhydride. Fluorinated triflates 11 were employed for the preparation of bis(polyfluoroalkylated) cyclopentadienes 9, which are potential ligands for homogeneous catalysts used in fluorous biphase systems. Fluorotriflates 11 are also excellent substrates for the preparation of various polyfluorinated compounds, e.g. nitriles or azides, by nucleophilic substitution.Homogeneous catalysis in biphase systems containing fluorous phase belongs to the most attractive topics in recent organofluorine chemistry. 1,2 An essential part of these systems consists of a homogeneous catalyst with significant fluorophilic properties, which are introduced into the molecule by means of fluorophilic ligands. These catalysts found also excellent use in reactions in supercritical CO 2 . 3 Sufficient fluorophilic properties of the catalysts are achieved provided that the overall fluorine content in the molecule is high. 4 This results in the need of fluorophilic ligands with multiple fluorinated chain. Phosphines with multiple fluorinated chains can be synthesized relatively easily and are hence mostly used for fluorophilic catalysts.Homogeneous catalysts with cyclopentadiene based ligands are very common and therefore it is surprising that only little attention has been paid to the synthesis of cyclopentadiene derivatives with fluorophilic properties. 5,6 Known cyclopentadienes contain only one fluorinated chain and hence their fluorophilic properties are insufficient. We were therefore interested in developing a strategy for the synthesis of cyclopentadienes with two attached fluorinated chains.Our first strategy for the preparation of bis(polyfluorinated) cyclopentadienes 9 started from cyclic epoxides. The epoxide ring in 1 was opened with vinylmagnesium bromide, then radical addition of a perfluoroalkyl iodide, iodide reduction and final dehydration gave 4 in 5.4% yield. 7 Although this strategy worked well for the model compound, 6-oxabicyclo[3.1.0]hexene (cyclopentene-1,2-oxide, 1), we obtained unexpected side-product 7 when attempting to prepare the target fluorocyclopentadienes 9 from 3,7-dioxatricyclo[4.1.0.0 2,4 ]-heptane 5 (see Scheme 1).We therefore turned our attention to methods which employ reactions of cyclopentadiene based carbanions with polyfluoroalkylated electrophiles. This approach was used earlier for the preparation of cyclopentadienes substituted by one polyfluoroalkyl chain (8). 6 We first prepared monopolyfluorinated cyclopentadiene 8 (mixture of 1-and 2-substituted isomers in about 1:1 ratio) according to the literature. 6 Lithiation by BuLi and then reflux of the carbanion formed with 2-(perfluorohexyl)ethyl iodide gave the bis-polyfluoroalkylated cyclopentadiene 9 in very poor yield, mostly because of low conversion of the reaction (Scheme 2). Scheme 1 i CH 2 = CHMgBr, CuI, THF, 0°C, 3 h, 54%; ii C 8 F 17 I, AIBN, 100°C, 1 h, 64%; iii...