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A new strategy for the synthesis of acyl β-C-glycosides is described. The reactivity of glyconitriles toward organometallic reagents such as organomagnesium or organolithium derivatives was studied, affording acyl β-C-glycosides in moderate to good yields. In this study, glycal formation was efficiently prevented by deprotonating the hydroxyl group in position 2 of the glyconitriles during the process.

N-phosphorylimines undergo Lewis acid-catalyzed Diels-Alder reactions with Danishefsky's diene. Application of the chiral catalyst zinc(II)-(S)-BINOL results in good-to-low asymmetric induction but poor chemical conversion. However, the absolute stereochemistry of novel aza-Diels-Alder cycloadducts, such as diethyl 4-oxo-2-phenyl-3,4-dihydropyridin-1(2H)-ylphosphonate, can be determined using circular dichroism (CD). Comparison between experimental and TDDFT-calculated CD spectrum shows that use of the (S)-catalyst results in predominant formation of the (6R) cycloadducts.

We propose here the synthesis and biological evaluation of 3,4-dideoxy-GalCer derivatives. The absence of the 3- and 4-hydroxyls on the sphingoid base is combined with the introduction of mono or difluoro substituent at C3 (analogues 8 and 9, respectively) to evaluate their effect on the stability of the ternary CD1d/GalCer/TCR complex which strongly modulate the immune responses. Biological evaluations were performed in vitro on human cells and in vivo in mice and results discussed with support of modeling studies. The fluoro 3,4-dideoxy-GalCer analogues appears as partial agonists compared to KRN7000 for iNKT cell activation, inducing T(H)1 or T(H)2 biases that strongly depend of the mode of antigen presentation, including human vs mouse differences. We evidenced that if a sole fluorine atom is not able to balance the loss of the 3-OH, the presence of a difluorine group at C3 of the sphingosine can significantly restore human iNKT activation.

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A series of hydrogen bonding organocatalysts was synthesized from dianhydrohexitol and was used for the first time in organocatalysis for Friedel-Crafts alkylation of indoles with nitroalkenes. Moderate yields and enantioselectivities were achieved.

This review presents an overview of the use of dianhydrohexitol derivatives as asymmetric ligands in organometallic catalysis or as asymmetric organocatalysts. For that purpose, we highlight two series of derivatives, the first preserving the original bis‐fused THF backbones, and the second originating from single THF ring‐opening reactions. These derivatives have been involved in different asymmetric reactions for the formation of C–H, C–C, C–N, or C–S bonds.

A stereospecific Mizoroki-Heck cross-coupling of differently substituted glycals with haloarenes resulting in the exclusive formation of either α- or β-aryl-C-glycosides depending solely on the configuration at C3 was achieved. The reaction was easy to set up because no specific precautions were required concerning moisture or oxygen, and it proceeded by a chirality transfer from C3 to C1. After optimization of cross-coupling conditions, various prepared glycals (7 examples) and arenes (10 examples) were tested, leading stereospecifically to the corresponding aryl-C-glycosides with a carbonyl group at C3, thus opening up new horizons for the total synthesis of glycosylated natural products.