PhPO-Modulated Kdo Glycosidation for Stereoselective Synthesis of β-Kdo-Containing Disaccharides.

A PhPO-modulated β-selective Kdo glycosidation approach is developed for the stereoselective synthesis of β-Kdo glycosides. With the readily available per--acetylated Kdo ynenoate as the donor, the glycosylation with a series of alcohols in the presence of PhPAuOTf and PhPO in toluene at low temperatures afforded the desired Kdo glycosides with good to excellent β-selectivities. Furthermore, the PhPO-modulated approach was effectively applied to the synthesis of β-(2→4)- and β-(2→8)-linked Kdo-Kdo disaccharides for further biological studies.

Enhancing Crop Resilience: Insights from Labdane-Related Diterpenoid Phytoalexin Research in Rice ( L.).

Rice ( L.), as one of the most significant food crops worldwide, holds paramount importance for global food security. Throughout its extensive evolutionary journey, rice has evolved a diverse array of defense mechanisms to fend off pest and disease infestations.

Additive-assisted synthesis of α-Kdo glycosides with peracetylated glycosyl ynenoate as a donor.

A DMF-modulated glycosylation approach for the stereoselective synthesis of α-Kdo glycosides with readily accessible peracetylated Kdo ynenoate as a donor was described. By utilizing this approach, we completed the synthesis of various linkage types of Kdo-Kdo disaccharides and the α-Kdo-containing protected trisaccharide variant relevant to the lipopolysaccharide of strain Nine Mile.

Promoter-Controlled Synthesis and Conformational Analysis of Cyclic Mannosides up to a 32-mer.

Cyclodextrins are widely used as carriers of small molecules for drug delivery owing to their remarkable host properties and excellent biocompatibility. However, cyclic oligosaccharides with different sizes and shapes are limited. Cycloglycosylation of ultra-large bifunctional saccharide precursors is challenging due to the constrained conformational spaces.