Journal of Carbohydrate Chemistry最新文献

Pyrimidine and purine nucleosides have a remarkable and comprehensive impact on medicinal chemistry and pharmaceutical industries. They become key parts of the growing interdisciplinary area of antimetabolites. The paramount importance of the nucleoside analogs triggered their broader use in treatment of critical diseases such as cancer, malignancies, microbial infection, and autoimmune diseases. Recent advances in their synthetic strategies through microwave-assisted organic synthesis (MAOS) have been reviewed.

Lipoarabinomannan (LAM), mannosyl LAM (ManLAM), and mycolyl-arabinogalactan (mAG) are unique and ubiquitous cell wall constituents of Mycobacterium tuberculosis (M. tb), the bacterium causing tuberculosis (TB), one of the deadliest diseases worldwide. It has been well documented that LAM, ManLAM, and mAG play an important role in mycobacterial infections and in the elicitation of specific immune responses against M. tb in the host. Therefore, LAM, ManLAM, mAG, and related molecules are attractive targets for the development of novel diagnostic and therapeutic strategies for TB. Accordingly, great research efforts have been spent on the chemical synthesis and biological studies of mycobacterium-related arabinofuranosyl oligosaccharides and their mimetics and conjugates. This article provides an extensive review about the progresses in this area. Due to the page limit of the journal, this review is published separately in three parts. Part I is focused on various glycosylation methods or strategies and protection tactics for stereoselective and stereospecific construction of α- and β-arabinofuranosyl linkages, as well as their applications to the synthesis of simple to highly complex mycobacterium-related arabinofuranosyl oligosaccharides containing only α-linked or both α- and β-linked arabinofuranosyl residues.

Complex polysaccharides have numerous pharmacological activities, such as antioxidant, antibacterial, antiviral, immunomodulating, anticoagulant and anticancer effects. In personal care products, these biopolymers are used as thickener and stabilizing agents or as moisturizing ingredients that could be beneficial to the skin. Various polysaccharides, such as glycosaminoglycans (GAGs), hyaluronic acid (HA), carrageenan, fucose, fucoidan, chitin, chitosan, etc., have applications in cosmeceutical industries. GAGs and HA incorporated in moisturizing creams strengthen the skin barrier by forming a protective layer which prevents transdermal water loss. Therefore, these polysaccharides have been formulated into potential cosmeceuticals and biopharmaceuticals.

Based on docking computation, a panel of lactoside derivatives have been designed as galectin-3 inhibitors. Suitable functional group modifications at C′-3 of methyl lactoside were predicted to supply some additional π–cation, π…H–O, and hydrogen bond interactions between the designed substrates and galectin-3 residues. The selected compounds, giving higher TotalScore in docking calculations, were thus synthesized, and their binding affinities toward galectin-3 were evaluated with SPR assay.

Two chitosan silica hybrid materials were prepared by a two-step process in 78–84% yields using the homogeneous phase reaction of 3-(triethoxysilyl)propyl isocyanate with chitosan dissolved in 1-n-butyl-3-methylimidazolium chloride ionic liquid (∼10% w/w), which was followed by NH₄OH catalyzed hydrolysis of triethoxysilyl groups and then sol-gel process. These new hybrid materials were shown to adsorb up to about 95% of Fe³⁺ from 5 × 10⁻⁴ M aqueous solution at room temperature in 24 h.

The judicious combination of shaping and recognition elements in cage-type architectures represents a powerful strategy to access molecular devices with tailored receptor properties and controlled abilities to form supramolecular assemblies. Aromatic modules are particularly attractive for these endeavors: they can play the role of rigid walls to build permanent cavities, folding screens between preexisting compartments and/or act as functional components promoting noncovalent self-interactions as well as associations with third species, allowing several levels of organization to be implemented. The field of cyclodextrins has enormously benefitted from the amalgamation with aromatic building blocks to give birth to hybrids with a much broader spectrum of properties and applications. The progress in precision chemistry has further enabled the efficient preparation of multiply-linked cap, hinge or clip cyclodextrin-aromatic chimeras with unprecedented level of control, which has translated into new developments in fields like supramolecular catalysis, self-assembly or gene delivery. This review article focuses specifically in these type of compounds, highlighting the intimate relationship between structure, supramolecular properties and performance in the target application.

General strategies on the construction of 1,2-branched trans-β-glycosidic linkages and the corresponding logics are discussed herein. Linear strategies usually require a temporary acyl protecting group at C2-O position of the glycosylation donors to secure the requisite β-selective glycosylation. Convergent strategies involve selective formation of the trans-β-glycosidic linkages in the absence of neighboring participation, wherein solvent participation, invertive glycosylation, as well as other effects have to be exploited to achieve the β-selective glycosylation. These strategies are illustrated by representative applications in the synthesis of saponins.