Temsirolimus metabolic pathways revisited.

Temsirolimus, a derivative of sirolimus, exhibits potent antitumor properties. It was the goal of this study to identify yet unknown temsirolimus metabolites generated after incubation with human liver microsomes. Previously, 23-hydroxy-, 24-hydroxy, 12-hydroxy, hydroxy-piperidine and 27--desmethyl temsirolimus had been described.

Fully digital workflow for presurgical orthodontic plate in cleft lip and palate patients.

Objective: In most cases, according to our treatment concept, a presurgical orthodontic treatment (POT) is performed on patients with cleft lip and palate (CLP). The aim of this case report is to demonstrate a completely digital workflow for the production of a palate plate.

Materials And Methods: For the assessment of the maxillary arch, a digital impression of the jaw was made on two patients with an intraoral scanner (Cerec Omnicam Ortho).

Generation of Aryl Radicals through Reduction of Hypervalent Iodine(III) Compounds with TEMPONa: Radical Alkene Oxyarylation.

A novel method for selective generation of aryl radicals from diaryliodonium salts and iodanylidene malonates with sodium 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPONa) as a single-electron transfer (SET) reducing reagent is described. In the presence of various alkenes, aryl radicals formed after SET-reduction of hypervalent iodine compounds undergo alkene addition and the adduct radicals that are thus generated are efficiently trapped by the concomitantly generated TEMPO radical to eventually afford oxyarylated products in moderate to very good yields. The efficiency of aryl radical generation of various iodine(III) reagents is studied and the generation of an iodanylidene malonate aryl radical is also investigated by computational methods.

Radical aminooxygenation of alkenes with N-fluoro-benzenesulfonimide (NFSI) and TEMPONa.

Reaction of various alkenes with commercially available N-fluorobenzenesulfonimide (NFSI) and TEMPONa provides the corresponding aminooxygenation products in moderate to good yields. Single electron transfer from readily generated TEMPONa to NFSI allows for clean generation of the corresponding bissulfonylamidyl radical along with TEMPO. N-radical addition to an alkene and subsequent TEMPO trapping provides the corresponding aminooxygenation product.

Preparation of phenanthrenes from ortho-amino-biphenyls and alkynes via base-promoted homolytic aromatic substitution.

A transition-metal-free phenanthrene synthesis starting from readily accessible ortho-amino-biaryls is presented. The biarylamines are in situ transformed into the corresponding diazonium salts which upon single electron reduction give the corresponding aryl radicals. Addition to an alkyne and subsequent base promoted homolytic aromatic substitution (BHAS) provide phenanthrenes in moderate to good yields.

Cyclizing radical carboiodination, carbotelluration, and carboaminoxylation of aryl amines.

Radical carboiodination of various aryl amines is reported. Aryl diazonium salts, generated in situ from the corresponding aryl amines, are reacted with Bu4NI to provide the corresponding aryl radicals which undergo 5-exo or 6-exo cyclization. Iodine abstraction eventually affords the carboiodinated products in good to excellent yields.

Catalytic regioselective oxidation of glycosides.

Discrimination among equals: A catalytic method for the selective oxidation of unprotected glycosides, both monosaccharides and disaccharides, has been developed. The resulting ketosaccharides are isolated in moderate to excellent yields. This approach provides a basis for protecting-group-free synthetic transformations of carbohydrates.

Transition-metal-free oxyarylation of alkenes with aryl diazonium salts and TEMPONa.

The reaction of readily available TEMPONa with aryl diazonium salts allows for clean generation of the corresponding aryl radicals along with TEMPO. Aryl radical addition to alkenes with subsequent TEMPO trapping provides the corresponding oxyarylation products in good to excellent yields. These experimentally easy to conduct transformations occur in the absence of any transition metal under mild conditions, and the process shows broad functional group compatibility.

Simple and rapid quantification of gadolinium in urine and blood plasma samples by means of total reflection X-ray fluorescence (TXRF).

A simple and rapid method to determine gadolinium (Gd) concentrations in urine and blood plasma samples by means of total reflection X-ray fluorescence (TXRF) was developed. With a limit of detection (LOD) of 100 μg L(-1) in urine and 80 μg L(-1) in blood plasma and a limit of quantification (LOQ) of 330 μg L(-1) in urine and 270 μg L(-1) in blood plasma, it allows analyzing urine samples taken from magnetic resonance imaging (MRI) patients during a period of up to 20 hours after the administration of Gd-based MRI contrast agents by means of TXRF. By parallel determination of the urinary creatinine concentration, it was possible to monitor the excretion kinetics of Gd from the patient's body.