Protecting group/halogen effect of N-glycosylamines on the self assembly of organogelator

Abstract

A series of N-glycosylamine based organogelators were synthesised from three different 4,6-O-protected saccharides. All these compounds were characterized using different spectral techniques. The effect of substituents present in the N-glycosylamines on gelation was studied from NMR and computation. Among the eighteen different gelators studied, 3b, bearing fluorine as a substituent, was observed to gelate at very low concentrations (CGC: 1%). Further, it is revealed that dipole–dipole interactions play an important role in the case of N-glycosylamine-based gelators. The presence of π–π stacking and H-bonding, as inferred from the reported X-ray diffraction data, are responsible for the gelation. Various possible modes of interaction are identified from computational studies. The gelation properties of these compounds were studied with regard to their molecular structure by scanning electron microscopy, differential scanning calorimetry, FT-IR and NMR studies.