RESUMO
A practical synthetic path for the preparation of trans-CF3SF4-substituted amines has been described. Primary and secondary amines bearing a variety of different functional groups including amino acids, cyclic amines, and nucleosides were prepared. The desired amines were synthesized under mild conditions. The influence of the CF3SF4-group on the pKa and log D of a standard amine was established. The unusual conformation of the trans-CF3SF4-substituted tosylate has been verified via its crystal structure.
RESUMO
The cross-metathesis reactions of trans-tetrafluoro(trifluoromethyl)-λ6-sulfanyl (CF3SF4)-containing olefins expand the repertoire of synthetic transformations of CF3SF4-substituted molecules. Treatment of a primary alkene and 3-CF3SF4-propene with a second-generation Hoveyda-Grubbs catalyst yielded the cross-metathesis product in good yield under very mild conditions (room temperature). CF3SF4-propene undergoes cross metathesis with substrates containing electron-withdrawing groups or electron-donating groups at room temperature or under dichloromethane reflux. The formation of the CF3SF4-propene homodimer and the utility of that dimer to undergo selective cross-metathesis reactions are described.
RESUMO
The understanding of the role of sphingolipid metabolism in cancer has tremendously increased in the past ten years. Many tumors are characterized by imbalances in sphingolipid metabolism. In many cases, disorders of sphingolipid metabolism are also likely to cause or at least promote cancer. In this review, sphingolipid transport proteins and the processes catalyzed by them are regarded as essential components of sphingolipid metabolism. There is much to suggest that these processes are often rate-limiting steps for metabolism of individual sphingolipid species and thus represent potential target structures for pharmaceutical anticancer research. Here, we summarize empirical and biochemical data on different proteins with key roles in sphingolipid transport and their potential role in cancer.
Assuntos
Proteínas de Transporte/metabolismo , Neoplasias/metabolismo , Esfingolipídeos/metabolismo , Animais , Antineoplásicos/uso terapêutico , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Neoplasias/tratamento farmacológicoRESUMO
Trichobezoar are foreign bodies formed from undigested hairs that accumulate in the gastrointestinal tract and cause obstruction. Trichobezoar are usually found in the stomach but when the tail of the bezoar extends into the small intestine it is referred to as Rapunzel syndrome. Patients are usually females and have a history of psychiatric illness. However, in this study, we present two cases of Rapunzel syndrome in adult male patients that were managed with surgery. Trichobezoar should be considered in all patients with a history of psychiatric illness presenting with abdominal symptoms regardless of gender.