Synthesis of 12β-Methyl-18--bile Acids.

Decoupling the roles of the farnesoid X nuclear receptor and Takeda G-protein-coupled bile acid receptor 5 is essential for the development of novel bile acid therapeutics targeting metabolic and neurodegenerative diseases. Herein, we describe the synthesis of 12β-methyl-18--bile acids which may serve as probes in the search for new bile acid analogues with clinical applicability. A Nametkin-type rearrangement was applied to protected cholic acid derivatives, giving rise to tetra-substituted Δ- and Δ-unsaturated 12β-methyl-18--bile acid intermediates ( and ).

Design, Synthesis and Biological Evaluation of Isoxazole-Based CK1 Inhibitors Modified with Chiral Pyrrolidine Scaffolds.

In this study, we report on the modification of a 3,4-diaryl-isoxazole-based CK1 inhibitor with chiral pyrrolidine scaffolds to develop potent and selective CK1 inhibitors. The pharmacophore of the lead structure was extended towards the ribose pocket of the adenosine triphosphate (ATP) binding site driven by structure-based drug design. For an upscale compatible multigram synthesis of the functionalized pyrrolidine scaffolds, we used a chiral pool synthetic route starting from methionine.

N-(2-Acetamido-2-de-oxy-β-d-gluco-pyranos-yl)-N-(3-azido-prop-yl)-O-methyl-hydroxyl-amine.

The structure of the title compound, C12H23N5O6, solved using adequate data from a thin crystal plate, confirmed that this useful glycoconjugate was obtained in the ring-closed β-pyran-ose configuration with (4) C 1 conformation. The mol-ecules are bound by O-H⋯O(OH) hydrogen bonds, notably in a zigzag C(2) chain along the short b (screw) axis, supplemented with an R 2 (2)(12) O-H⋯O(carbon-yl) link along the a axis and other C(2) links. The absolute configuration was not unambiguously determined but was known from the synthetic chemistry, which used natural 2-acetamido-2-de-oxy-d-glucose as the starting material.

Total synthesis of Lewis(X) using a late-stage crystalline intermediate.

Herein, we report on a highly efficient synthesis of a crystalline protected Lewis(X) trisaccharide that was converted to Lewis(X) following global deprotection. The trisaccharide was prepared in a highly convergent synthesis (seven steps, longest linear sequence) and in a 38% overall yield using a strategy that involved the regioselective glycosylation of a GlcNAc acceptor with a galactose thioglycoside donor, followed by fucosylation of the remaining free GlcNAc hydroxyl as key steps. The core trisaccharide also has the potential to be converted to other members of the Type-2 Lewis family of antigens due to the orthogonal nature of the protecting groups employed.

Crystal packing in three related disaccharides: precursors to heparan sulfate oligosaccharides.

The three title compounds form part of a set of important precursor dissacharides which lead to novel therapeutics, in particular for Alzheimer's disease. All three crystallize as poorly diffracting crystals with one independent mol-ecule in the asymmetric unit. Two of them are isostructural: 4-meth-oxy-phenyl 4-O-[6-O-acetyl-2-azido-3-O-benzyl-2-de-oxy-4-O-(9-fluor-en-yl-methyl-oxycarbon-yl)-α-d-gluco-pyranos-yl]-2-O-benzoyl-3-O-benzyl-6-O-chloro-acetyl-α-l-ido-pyran-oside, C59H56ClN3O16, (I), the ido-relative of a reported gluco-disaccharide [Gainsford et al.