Dodecabromo- and Dodecaiodocentrohexaindane: T -Symmetrical Key Building Blocks for Twelve-Fold Cross-Coupling Reactions and Six-Fold Orthogonal Extension.

Centrohexaindane was converted into its T -symmetrical 2,3,6,7,10,11,14,15,20,21,26,27-dodecabromo and -dodecaiodo derivatives using N-bromo- and N-iodosuccinimide, respectively, in the presence of trifluoromethanesulfonic acid as a catalyst in single, highly efficient steps. Sonication or microwave irradiation was indispensable to enforce exhaustive halogenation of the twelve equivalent peripheral positions of this Cartesian polyaromatic hydrocarbon. Despite their extremely poor solubility in most organic solvents, the new dodecahalo derivatives were fully characterized, including single crystal X-ray structure analysis.

Rigid Triple Endoscopy Improves Clinical Staging of Primary Head and Neck Cancer.

Background: Correct pre-therapeutic staging of the first primary carcinoma (FPC) and detection of simultaneous second primary carcinomas (SSPCs) decisively influence therapy and prognosis of head and neck squamous cell carcinomas (HNSCC). The aim of this study was to determine the benefit of pre-therapeutic triple endoscopy for detection of SSPC and pre-therapeutic T category.

Methods: A cohort of 234 HNSCC patients with completed triple endoscopy was reviewed, focusing on pre-therapeutic T category and SSPC.

Centrohexaindane: six benzene rings mutually fixed in three dimensions - solid-state structure and six-fold nitration.

The solid-state molecular structure of centrohexaindane (), a unique hydrocarbon comprising six benzene rings clamped to each other in three dimensions around a neopentane core, and the molecular packing in crystals of ·CHCl3 are reported. The molecular Td-symmetry and the Cartesian orientation of the six indane wings of in the solid state have been confirmed. The course and limitation of electrophilic aromatic substitution of are demonstrated for the case of nitration.

A C(3v)-symmetrical tribenzotriquinacene-based threefold N-heterocyclic carbene. Coordination to rhodium(I) and stereoelectronic properties.

A novel tribenzotriquinacene-based tris-NHC has been obtained and coordinated to rhodium. The new ligand displays a unique rigid C3v symmetry. The electrochemical analysis of the tri-rhodium complex reveals that the three metals are essentially disconnected.

Implant therapy following liver transplantation: clinical and microbiological results after 10 years.

Background: The number of immunocompromised patients is increasing as a consequence of successful organ transplantation. Placing dental implants in these patients has been questioned because of their increased risk for infections. The 10-year follow-up data of a 71-year-old liver transplant recipient with long-term immunosuppressive therapy is reported.