Fluorous iminoalditols: a new family of glycosidase inhibitors and pharmacological chaperones.

A collection of new reversible glycosidase inhibitors of the iminoalditol type featuring N-substituents containing perfluorinated regions has been prepared for evaluation of physicochemical, biochemical and diagnostic properties. The vast variety of feasible oligofluoro moieties allows for modular approaches to customised structures according to the intended applications, which are influenced by the fluorine content as well as the distance of the fluorous moiety from the ring nitrogen. The first examples, in particular in the D-galacto series, exhibited excellent inhibitory activities.

The Amadori rearrangement as key reaction for the synthesis of neoglycoconjugates.

The Amadori rearrangement was introduced as a key step for the conjugation of carbohydrate moieties with suitable amines such as aliphatic amines and amino acid derivatives. The rearrangement products were further transformed into the corresponding 1-N,2-O cyclic carbamates employing triphosgene to obtain anomerically stable glycoconjugates. The reaction conditions were probed on a model substrate, 3,5-di-O-benzyl-alpha,beta-d-glucofuranose and further applied to d-glycero-d-gulo-heptose, which gave 'd-gluco-conjugates' in the alpha-anomeric form exclusively in high isolated yields.

Simultaneous detection of different glycosidase activities by 19F NMR spectroscopy.

A fast method for the simultaneous detection of different glycosidolytic activities in commercially available enzyme preparations and crude culture filtrates was found in using, as substrate, a mixture of different glycosyl fluorides and 19F NMR spectroscopy as a screening technique. Accompanying studies regarding the hydrolytic stability of these fluorides in various buffer systems, as well as conditions of their long-term storage, were carried out. A simple procedure for the preparation of beta-D-mannopyranosyl fluoride in gram quantities is given.

Stereochemical course of two arene-cis-diol dehydrogenases specifically induced in Pseudomonas putida.

Catabolism of nonphenolic arenes is frequently initiated by dioxygenases, yielding single isomer products with two adjacent hydroxylated asymmetric centers. The next enzymic reaction dehydrogenates these cyclic cis-diols, with aromatization yielding catechols for ring cleavage. There are two stereochemical questions to answer.