Intermolecular Dehydrative Coupling Reaction of Aryl Ketones with Cyclic Alkenes Catalyzed by a Well-Defined Cationic Ruthenium−Hydride Complex: A Novel Ketone Olefination Method via Vinyl C−H Bond Activation
摘要:
The cationic ruthenium hydride complex[(eta(6)-C(6)H(6))-(PCy(3))(CO)RuH](+)BF(4)(-) was found to be a highly effective catalyst for the intermolecular olefination reaction of aryl ketones with cycloalkenes. The preliminary mechanistic analysis revealed that an electrophilic ruthenium vinyl complex is the key species fir mediating both vinyl C-H bond activation and the dehydrative olefination steps of the coupling reaction.
Ceramide derivatives as modulators of immunity and autoimmunity
申请人:Porcelli A. Steven
公开号:US20070238673A1
公开(公告)日:2007-10-11
α-Galactosylceramides and glycosylceramides (“ceramide-like glycolipids”) that modulate NK T cells. The ceramide-like glycolipids vary in the cytokines induced in NK T cells and vary in the antigen-presenting cells that are capable of efficiently presenting the compounds to NK T cells. Pharmaceutical compositions of the ceramide-like glycolipids are provided, as are pharmaceutical compositions of the ceramide-like glycolipids combined with dendritic cells. Methods utilizing the ceramide-like glycolipids in vaccines, to activate NK T cells, to stimulate the immune system, and to treat mammals are also provided. The invention also provides methods of evaluating a compound for its ability to activate an NK T cell in the presence of a cell expressing a CD1d protein.