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We have developed a new series of glycoprobe-polymer dot ensembles for the fluorogenic, homogeneous detection of lectins. Electrostatic self-assembly between positively charged rhodamine-based glycosides and negatively charged poly(3-hexylthiophene-2,5-diyl)/poly(styrene-co-maleic anhydride) polymer dots produces the ensembles with a quenched fluorescence. Fluorescence spectroscopy showed that the ensembles exhibited a concentration-dependent fluorescence enhancement with selective lectins over a range of unselective lectins and proteins. This research provides insight into the development of simple fluorogenic probes for homogeneous lectin analyses based on the supramolecular assembly between polymeric nanoparticles and fluorescent glycoprobes.

This study describes an interesting observation that the mixture of anomeric galactolipids has synergistic effects on the growth inhibition of human multiple myeloma (MM) cells. We determine that the equivalent mixture of a pair of α- and β-galactolipids with a 14-carbon lipid chain can cause stronger poly ADP-ribose polymerase cleavage and DNA damage, producing more late apoptotic MM cells, than either anomer alone.

Glycoligands, which feature a glycoside as the central template incorporating Lewis bases as metal chelation sites and various fluorophores as the chemical reporter, represent a range of interesting scaffolds for development of chemosensors. Here, new types of triazolyl bidentate glycoligands (TBGs) based on the grafting of 3-azidocoumarin to the C2,3- or C4,6-positions of three epimeric pyranoglycosides including a glucoside, a galactoside, and a mannoside were efficiently synthesized via a fluorogenic dual click reaction assisted by microwave irradiation. The desired TBGs were afforded in high conversion rates (>90%) and reasonable yields (∼70%). Moreover, a preliminary optical study of two hydroxyl-free glucoside-based TBGs indicates that these compounds are strongly fluorescent in pure water, implying their potential for ion detections in aqueous media.

Triazolyl glycolipid derivatives constructed via CuI-catalyzed azide-alkyne 1,3-dipolar cycloaddition reaction (Cue-AAC) represent a new range of carbohydrate-based scaffolds for use in many fields of the chemical research. Here the surface adsorptive ability of series of our previously prepared C1- or C6-triazole linked gluco- and galactolipid derivatives for mild steel in 1 M HCl was studied via electrochemical impedance spectroscopy (EIS). Results indicated that these monosaccharide–fatty acid conjugates are weak inhibitors against HCl corrosion for mild steel. Moreover, some newly synthesized triazolyl disaccharide (maltose)–fatty alcohol conjugates failed to display enhanced activity, meaning that the structural enlargement of the sugar moiety does not favor the iron surface adsorption. However, a bis-triazolyl glycolipid derivative, which was realized by introducing a benzenesulfonamide group via Cue-AAC to the C6-position of a C1-triazolyl glucolipid analog, eventually showed significantly improved adsorptive potency compared to that of its former counterparts. The corrosion inhibitive modality of this compound for mild steel in HCl was subsequently studied via potentiodynamic polarization and thermodynamic calculations.

β- C -Glucosyl and β- C -galactosyl-1,4-dimethoxynaphthalenes have been synthesized using a F 3 CCO 2 Ag/SnCl 4 promoted Friedel–Crafts electrophilic substitution reaction. Both glycosyl acetates and methyl glycosides can be used as glycosyl donors. Further oxidation afforded the corresponding β- C -glycosyl-1,4-naphthoquinones. The in vitro cytotoxic activity of these compounds was evaluated against the A375 cell line.

A bis-triazolyl phenylalaninyl galactoside was synthesized by a two-fold click reaction between an azido phenylalanine and a di-O-propynyl galactoside. By a cytotoxicity assay the compound was determined to be selectively toxic for multiple myeloma (MM) among a series of cancer cell lines with no toxicity to a control cell line. A Western blot analysis suggested that this compound could potentiate the cleavage of poly ADP-ribose polymerase in MM cells, leading to apoptosis.

1- or 6-Triazologluco- and galactolipid derivatives bearing a lipid chain length of 16 carbons were efficiently constructed via click chemistry. The differentiation in their surface pressure-molecular area (π–A) isotherms first implies that these structurally and configurationally diverse amphiphiles adopt different distribution manner at air–water interfaces. The Langmuir–Blodgett (LB) films of the synthesized glycoconjugates on mica surface were subsequently prepared and visualized via atomic force microscopy (AFM), which exhibited diverse topographies and possess different contact angles with water. These data further suggest that the structural variation as well as epimeric identity of triazologlycolipids may result in their distinct interfacial behaviors at the air–solid interface. Furthermore, the addition of increasing amounts of 1-triazologalactolipid 2 to poly-diacetylene (PDA) was determined to impact the π–A isotherm of the latter, prompting us to further fabricate new colorimetrically detectable mixed-type vesicles containing triazologlycolipids for biochemical studies.

The synthesis of triazole-linked glycosyl acetophenone, benzoic acid, and α-ketocarboxylic acid derivatives was readily achieved via Cu(I)-catalyzed azide–alkyne cycloaddition (‘click’ reaction) in excellent yields of 93–97%. Among the synthesized glycoconjugates, the triazolyl α-ketocarboxylic acids were identified as the most potent protein tyrosine phosphatase 1B (PTP1B) inhibitors with micromole-ranged IC 50 values and moderate-to-good selectivity over a panel of homologous PTPs including TCPTP (4.6-fold), LAR (>30-fold), SHP-1 (>30-fold) and SHP-2 (>30-fold). Moreover, a docking simulation was conducted to propose a plausible binding mode of the glucosyl α-ketocarboxylic acid triazole with the enzymatic target.

Carbohydrates are important as signaling molecules and for cellular recognition events, therefore offering scope for the development of carbohydrate-mimetic diagnostics and drug candidates. As a consequence, the construction of carbohydrate-based bioactive compounds and sensors has become an active research area. While the advent of click chemistry has greatly accelerated the progress of medicinal chemistry and chemical biology, recent literature has seen an extensive use of such approaches to construct functionally diverse carbohydrate derivatives. Here we summarize some of the progress, covering the period 2010 to mid-2015, in CuI-catalyzed azide-alkyne 1,3-dipolar cycloaddition CuAAC “click chemistry” of carbohydrate derivatives, in the context of potential therapeutic and diagnostic tool development.