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The rhodium-catalyzed asymmetric allenylation of sulfonylimines is disclosed providing silyl homoallenylamide products in up to 99:1 er. Through subsequent activation of the C−N bond of the silyl homoallenyl sulfonamide, palladium-catalyzed stereospecific allylic allenylation could be achieved giving C−C bond formation with high chirality transfer. The synthetic utility of both the silyl homoallenyl sulfonamides and the silyl homoallenyl malonates as bis(nucleophiles) is demonstrated. [ABSTRACT FROM AUTHOR]

A new, simple, and efficient method for the synthesis of both α- and β-glycosyl amides using solvent-free conditions is described. This method involves the coupling of glycosyl amines with the p -nitrophenol esters of lipids as a key step. [ABSTRACT FROM AUTHOR]

A newfamily of P-chiral P,π-hybridligands was prepared from the dihydrobenzooxaphosphole core. Thesenew ligands were demonstrated to be both sterically and electronicallytunable at the substituents on the phosphorus atom andthe π-system of the ligand. Application of these new ligandsto the catalytic asymmetric addition of boronic acids to imine electrophileswas shown to proceed with high levels of enantioinduction. [ABSTRACT FROM AUTHOR]

Summary Glycosylceramides that activate CD1d-restricted invariant natural killer T ( i NKT) cells have potential therapeutic applications for augmenting immune responses against cancer and infections. Previous studies using mouse models identified sphinganine variants of α-galactosylceramide as promising i NKT cell activators that stimulate cytokine responses with a strongly proinflammatory bias. However, the activities of sphinganine variants in mice have generally not translated well to studies of human i NKT cell responses. Here, we show that strongly proinflammatory and anti-tumor i NKT cell responses were achieved in mice by a variant of α-galactosylceramide that combines a sphinganine base with a hydrocinnamoyl ester on C6″ of the sugar. Importantly, the activities observed with this variant were largely preserved for human i NKT cell responses. Structural and in silico modeling studies provided a mechanistic basis for these findings and suggested basic principles for capturing useful properties of sphinganine analogs of synthetic i NKT cell activators in the design of immunotherapeutic agents. [ABSTRACT FROM AUTHOR]

Reduction of glycosyl azides to amines followed by coupling with p-nitrophenol esters of lipids as key step provides α- and β-glycosyl amides. [ABSTRACT FROM AUTHOR]