Covalent Inhibitors of KEAP1 with Exquisite Selectivity.

The NRF2-KEAP1 interaction is central for cytoprotection against stresses, giving it high clinical significance. Covalent modification of KEAP1 is an efficient approach, but the covalent inhibitors used in the clinic carry undesired side effects originating in their moderate selectivity. Starting with a phenotypic screen, we identified a new covalent inhibitor chemotype that was optimized to deliver a series of potent and highly selective KEAP1 binders.

An efficient synthesis of L-idose and L-iduronic acid thioglycosides and their use for the synthesis of heparin oligosaccharides.

Efficient preparations of thioglycoside derivatives of L-idose and L-iduronic acid are described. The method avoids the tedious chromatographic separations of furanose and pyranose anomeric mixtures, and affords the thioglycosides in a stereoselective manner. The L-idose and L-iduronic acid thioglycosides having combinations of different protecting groups proved to be efficient glycosyl donors in the synthesis of heparin disaccharides.

A new, powerful glycosylation method: activation of thioglycosides with dimethyl disulfide-triflic anhydride.

Dimethyl disulfide reacts with triflic anhydride to provide a highly reactive electrophile. Various thioglycosides, differing in their thio aglycons, carbohydrate units, and protecting group pattern, were activated with Me2S2-Tf2O in the presence of different glycosyl acceptors. The reactions proceeded at low temperatures within a short time, affording oligosaccharides in high yields both on primary and secondary hydroxyls.