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In the title molecule, C20H24Br2N4, the imidazopyridine moiety is not planar as indicated by the dihedral angle of 2.0 (2)° between the constituent rings; the 4-dimethylaminophenyl ring is inclined to the mean plane of the imidazole ring by 27.4 (1)°. In the crystal, two sets of C—H...π(ring) interactions form stacks of molecules extending parallel to the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H...H (42.2%), H...C/C...H (23.1%) and H...Br/Br...H (22.3%) interactions. The optimized structure calculated using density functional theory (DFT) at the B3LYP/ 6–311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated HOMO–LUMO energy gap is 2.3591 eV.

Oxidation of various 1-thioglycopyrano- and furanosides with H 2 O 2 /Ac 2 O/SiO 2 was performed in CH 2 Cl 2 /aprotic perfluorinated solvent mixtures (100:0 to 1:19, v/v). Reactions appeared much faster at a solvent ratio of 1:1 without significant over-oxidation to sulfones and modification of diastereoselectivity. Nevertheless, the nature of both the glycosyl moiety and the protecting group influenced the ( S S ):( R S ) product ratio.

The title compound, C13H9N3O3, crystallizes with two identical but differently oriented molecules in the asymmetric unit, the dihedral angle between the fused-ring systems of the two molecules being 64.39 (7)°. The two prop-2-ynyl chains are located on opposite sides of the molecule and are nearly perpendicular to the fused ring plane, as indicated by the C—N—C—C torsion angles in the range 106.0 (3)–113.4 (3)°. In the crystal, the two molecules are linked through C—H...O hydrogen bonds into dimers, which are subsequently linked by further C—H...O interactions, building a three-dimensional network.

Oxidation of various 1-thioglycopyrano- and furanosides with H 2 O 2 /Ac 2 O/SiO 2 was performed in CH 2 Cl 2 /aprotic perfluorinated solvent mixtures (100:0 to 1:19, v/v). Reactions appeared much faster at a solvent ratio of 1:1 without significant over-oxidation to sulfones and modification of diastereoselectivity. Nevertheless, the nature of both the glycosyl moiety and the protecting group influenced the ( S S ):( R S ) product ratio.

A variety of cyclic and acyclic allylic alcohols undergo efficient chemo-, regio- and/or stereoselective epoxidations in neutral aqueous solutions of amphiphilic carbohydrates (sucrose, L-arabinose, methyl or ethyl beta-D-fructopyranoside) by using dilute hydrogen peroxide in the presence of molybdic or tungstic salts.