•Twenty two heptaacetyl maltosyl/lactosyl triazoles have been synthesized.•Many of the maltose-linked triazoles are effective molecular gelators.•The gels could immobilize drug molecules for sustained release.Low molecular weight gelators are important for the study of supramolecular chemistry and have useful applications for biomaterials. Glycomimetics that are easily accessible and have useful gelation properties are especially interesting molecules. In this research, nine per-O-acetyl lactosyl- and thirteen per-O-acetyl maltosyl triazole derivatives were synthesized and analyzed. Most of the maltosyl triazoles and one of the lactosyl derivatives were found to be effective molecular gelators. The supramolecular gels were characterized using rheology and optical microscopy and they exhibited morphologies ranging from fibers to planar sheets. The self-assembling properties of selected lactosyl and maltosyl triazole derivatives were studied using 1H NMR spectroscopy at different temperatures. The NMR studies revealed that the triazole moiety in these compounds played an important role in the formation of the supramolecular assembly, but the sugar moiety configurations are more influential towards gelation. Naproxen and chloramphenicol were used as the model drugs to assess the potential of these compounds in drug delivery applications. A pH responsive gelator showed faster delivery of chloramphenicol at mild basic conditions than neutral conditions. The effective disaccharide triazole-based molecular gelators are useful for the preparation of advanced soft materials that have potential applications as matrix for immobilization of drugs or biomolecules.Download high-res image (671KB)Download full-size image

Carbohydrate based small molecular gelators are important classes of compounds which can form useful soft materials with many practical applications. Although many different types of effective gelators have been reported, the rational design of a molecular hydrogelator is still challenging. In this research, we combined the structural features of two classes of monosaccharide based molecular gelators and obtained a new class of glycolipids that can function as molecular gelators. These new compounds were synthesized by introducing a triazole functional group to a protected 2-glucosamine through Cu(I) catalyzed azide/alkyne cycloaddition reaction (CuAAC). A series of eighteen new glycolipids containing 4,6-O-benzylidene acetal protected D-glucosamide and triazole were synthesized and characterized. The self-assembling properties of these compounds were screened in several organic solvents, aqueous solutions, and water. All eighteen compounds are effective molecular gelators for at least one solvent and, more significantly, eleven compounds are hydrogelators with minimum gelation concentrations of 0.15–1.0 wt%. The hydrogels are suitable carriers for sustained release of chloramphenicol, and for the entrapment of toluidine blue dye. These results indicate that the D-glucosamide triazoles are effective templates for small molecular hydrogelators and are useful in designing sugar based soft materials.

Sugar based low molecular weight gelators have many potential uses for the formation of advanced soft materials. Here we have synthesized a series of peracetylated d-glucosamine triazole derivatives via the Cu catalyzed azide/alkyne cycloaddition reaction (CuAAc) and studied their self-assembling properties in several organic solvents, aqueous solutions, and water. Among the sixteen compounds synthesized and studied, many were able to function as organogelators for multiple solvents. Also seven compounds were able to form hydrogels at low concentrations such as 0.2–1.0 wt %. These indicate that peracetylated d-glucosamine triazole analogs are effective small molecular gelators.

We report the synthesis and self-assembling properties of a new class of glucosyl triazole derivatives from glucose. The compounds are synthesized by a Cu(I) catalyzed azide/alkyne cycloaddition reaction, or the ‘click’ reaction. Several efficient low molecular weight organogelators were obtained in this study. We found that triazole analogs containing long alkyl hydroxyl groups and phenyl groups typically are effective in forming supramolecular gels.

Diacetylene-containing glycolipids are a unique class of compounds that are able to self-assemble and form ordered supramolecular structures. Polymerizable diacetylene glycolipids that can function as low molecular weight gelators are particularly interesting molecules which can lead to stimuli-responsive smart materials. To discover efficient organogelators with built-in functionality that may be useful in sensing local environmental changes, we have synthesized a series of novel diacetylene-containing amide and urea derivatives using d-glucosamine as the starting material. Both amphiphilic and dipolar glycolipids were synthesized, and these compounds are effective gelators for several organic solvents and aqueous solutions. The resulting gels can be cross-linked under 6 W UV light to produce blue or purple polydiacetylene gels. The cross-linked gels obtained from urea derivatives are generally dark blue and exhibit blue to red color transitions upon heating. Compared to the urea derivatives, the analogous diacetylene amides produced blue to deep purple polymerized gels, depending on the structures of the gelators. The morphologies of the gels were characterized by optical microscopy and scanning electron microscopy. Typically, self-assembled fibrous networks were observed. The synthesis and characterization of these polymerizable gelators and their UV–vis absorption upon polymerization are reported.

We report the synthesis and self-assembling properties of a new class of tripeptoids synthesized by a one-pot Ugi reaction from simple starting materials. Among the focused library of tripeptoids synthesized, several efficient low molecular weight gelators were obtained for aqueous DMSO and ethanol mixtures.

We report the synthesis and self-assembling properties of a new class of tripeptoids synthesized by a one-pot Ugi reaction from simple starting materials. Among the focused library of tripeptoids synthesized, several efficient low molecular weight gelators were obtained for aqueous DMSO and ethanol mixtures.