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Research has been conducted on the protected anhydroalditols. The reaction of these compounds with (diacetoxyiodo)benzene, iodosylbenzene and iodine has been investigated and the results demonstrate that the reaction can be an intramolecular glycosidation carried out via hydrogen abstraction promoted by the alkoxy radical and transient C-radical intermediate oxidation.

Research has been conducted on the anomeric nitrate esters and N-phthalimino glycosides of carbohydrates in furanose and pyranose forms. The synthesis of these compounds has been carried out in generating the alkoxy radicals and in investigating the C1-C2 fragmentation reaction under the reductive conditions.

Research has been conducted on the piperidine and pyrrolidine type imino sugars. The methodology developed to obtain these sugars is described.

A technique for synthesizing alduronic acid lactones through the fragmentation of carbohydrate anomeric alkoxy radicals is presented. Specifically, the method results to the simultaneous one-carbon degradation and cyclization of aldopyranosuronic and aldofuranosuronic acid lactones. Reactions under this method is facilitated by diphenylhydroxyselenium acetate-iodine under visible light irradiation and (diacetoxyiodo)benzene-iodine under mild conditions.

The ability of the guanidinylating reagent N' ,N' -diBoc-N-triflyl-guanidine (GN-Tf) to react with in situ formed free amines from azides in carbohydrates scaffolds is analyzed. This reaction method has helped in preparing guanidine derivatives in a one-pot manner, either with primary or secondary azides with different substitution patterns.

Research has been conducted on carbohydrate derivatives of chiral 7-oxa-2-azabicyclo[2.2.1]heptane and 8-oxa-6-azabicyclo[3.2.1]octane ring systems. The authors describe the synthesis of these derivatives.

Esters and carbonates can be used as electron-withdrawing groups to derive alpha-iodoalkyl esters and alpha-iodoalkyl carbonates. The reaction of a number of carbohydrates of the threose and erythrose series with either an ether or an ester group at C2 with the system (diacetoxyiodo)benzene/iodine showed that the 2,3-O-isopropylidene-D-ribose derivative is transformed into the erythrose acetyl acetal derivative in good yield and with high selectivity, while the 2,3-carbonate yielded the alpha-iodoalkyl carbonate as an inseparable mixture of 1R and 1S isomers.

Initial beta-fragmentation reaction of the hemiacetal alcohol promoted by the development of anomeric alkoxy radical produced with the hyppervalent iodine reagent/I2 system under mild conditions and intramolecular trapping of the C2 radical originated in the fragmentation phase with an appropiately placed alcohol group were used in a tandem procedure to obtain cyclic carbohydrates. The procedure would provide cyclic aldotetrosoes or aldopentoses. The iodosylbenzene/I2 system was employed.

Investigates the synthesis of alpha-iodoalkyl esters and carbonates from carbohydrates. Formation of glycopyran-1-O-yl and glucofuran-1-O-yl radicals by reaction of carbohydrate anomeric alcohols with hypervalent iodine reagents; Feasibility of applying chromatography to hexoses of the glucose.

This study delves into the intriguing properties of the 1H/1T-TaS 2 van der Waals heterostructure, focusing on the transparency of the 1H layer to the charge density wave of the underlying 1T layer. Despite the sizable interlayer separation and metallic nature of the 1H layer, positive bias voltages result in a pronounced superposition of the 1T charge density wave structure on the 1H layer. The conventional explanation relying on tunneling effects proves insufficient. Through a comprehensive investigation combining low-temperature scanning tunneling microscopy, scanning tunneling spectroscopy, non-contact atomic force microscopy, and first-principles calculations, we propose an alternative interpretation. The transparency effect arises from a weak yet substantial electronic coupling between the 1H and 1T layers, challenging prior understanding of the system. Our results highlight the critical role played by interlayer electronic interactions in van der Waals heterostructures to determine the final ground states of the systems.

The fragmentation of anomeric alkoxyl radicals (ARF) and the subsequent intramolecular cyclization promoted by hypervalent iodine reagents provide an excellent method for the synthesis of tetrazolo-sugars. This new reaction offers additional advantages for the synthesis of these compounds, including the ready availability of the starting materials, experimental simplicity, mild conditions, and good yields.

[reaction: see text]. The beta-fragmentation of 2,2-difluoro-saccharide anomeric alkoxyl radicals, generated under oxidative condition by treatment of the respective alcohols with (diacetoxyiodo)benzene (DIB) and iodine, afforded 1,1-difluoro-1-iodo alditols in high yield. The reactivity of the fluorinated radical generated by rupture of the C-I bond has been preliminarily assessed by reductive deiodination with tributyltin hydride/AIBN and intermolecular allylation using the Keck reaction.

[reaction: see text] The alkoxy radical generated by reaction of 3,7-anhydro-2-deoxyoctitols with (diacetoxyiodo)benzene (DIB) and iodine abstracts regioselectively either the proton at C7 or that at C4 depending on the electronegativity of the substituent at C4. The correct election of this substituent can switch the reaction to give 2,9-dioxabicyclo[3.3.1]nonane or hexahydro-2H-furo[3,2-b]pyran ring systems.