Synthetic Applications of Cyclic Sulfites, Sulfates and Sulfamidates in Carbohydrate Chemistry

Improved Synthesis for Modular Ascarosides Uncovers Biological Activity

“…Inspired by the work of van Boom and co-workers, 26 we then considered a strategy based on regioselective opening of cyclic sulfates, whose utility is being increasingly recognized in carbohydrate chemistry. 27 Commercially available methyl l -rhamnopyrano-side 6 was treated with 2,2-dimethoxypropane to afford 7, followed by TBDPS protection. In the presence of excess TBDPSCl, acetonide deprotection occurred during silica gel chromatography to directly afford diol 8 in nearly quantitative yield.…”

Synthesis of S‐ and N‐Functionalized Dithiocarbamates from Cyclic Sulfates

“…With these results in hand, as a proof of concept, the methodology was extended to sodium DTC salts of other simple amines, namely, sec ‐butylamine and pyrrolidine (compounds 5b and 5c ) as well as to more complex cyclic sulfates such as those derived from xylose and glucose, 2 32 and 3 ,33 respectively (Scheme ). Cyclic sulfates derived from saccharides represent valuable building blocks for the preparation of a wide variety of sugar‐related compounds30a owing to the combination of their straightforward and efficient formation, and their high chemical stability and reactivity. DTCs that are sugar‐linked at the anomeric and nonanomeric positions have previously been prepared through nucleophilic displacement of glycosyl halides with dialkyl‐DTC anions 1b,34.…”

“…To the best of our knowledge, there are no reports on the synthesis of functionalized DTCs based on cyclic sulfates as direct precursors. As part of our ongoing exploration of the synthetic utilities of cyclic sulfates,30a we envisioned that ring opening of cyclic sulfates by DTC anions would be a plausible approach to the synthesis of functionalized DTCs. Herein, we report a novel and efficient method for the synthesis of DTCs with different substitution patterns either at the thiol or at the amine chain by coupling of cyclic sulfates as electrophilic reagents with simple starting materials, including amines and carbon disulfide, by means of environmentally benign protocols.…”

Masked Thiol Sugars: Chemical Behavior and Synthetic Applications of S‐Glycopyranosyl‐N‐monoalkyl Dithiocarbamates

“…In line with our continuing activities on the exploration of the synthetic utilities of vinyl sulfone [27] and cyclic sulfates, [28] we decided to exploit the high electrophilic reactivity of those functions for our purposes.…”

“…The selection of this compound as a representative example of the cyclic sulfate family was based on the well-established value of cyclic sulfates derived from saccharides as building blocks for the preparation of a wide variety of sugar-related compounds on account of the combination of their straightforward and efficient formation and their high chemical stability and reactivity. [28] By performing the indicated reactions, the corresponding heterodivalent neoglycoconjugates 15-16 were obtained in a regiospecific manner by the nucleophilic ring attack of the unmasked thiolates generated from the basic treatment of the sugar DTCs on the cyclic sulfate ring at the less hindered carbon atom. This reactivity is in accordance with the usual chemical reactivity reported for such cyclic sulfates.…”