Synthesis and Properties of New Glucocationic Surfactants:  Model Structures for Marking Cationic Surfactants with Carbohydrates

Abstract

[reaction: see text] In this work, we report the synthesis of a new series of glucocationic surfactants, a class of surfactants we introduced very recently. The preparation of the surfactants is based on the synthesis of the 2-bromoethyl-2,3,4,6-tetra-O-acetyl-beta-D-glucopyranoside, whose preparation was studied in order to improve yields and stereoselectivity of this key intermediate. These glucocationic amphiphiles were prepared and studied as a model of cationic surfactants marked with a carbohydrate moiety. The use of carbohydrates as markers on cationic lipids was recently introduced to induce recognition by specific receptors, present on the surface of cell membranes. The chemicophysical characterization of these model structures can give more insight on the aggregation behavior. Conductivity and surface tension measurements were performed in order to characterize the compounds from the amphiphilic point of view. The results showed a different effect of the glucosidic moiety on the cmc value with respect to the glucopyridinium cationic surfactants. The surfactants also showed the tendency to form premicellar aggregates in solution when the hydrophobicity is raised.

Synthesis and Characterization of Highly Fluorinated Gemini Pyridinium Surfactants

“…In fact, the formation of these ion pairs is normally favoured when the concentration is increased [18] and should be more evident, if occurring, for monomeric surfactants, since they have a higher cmc. As we [28] and others [18,29] have recently found for gluco-cationic surfactants, several surfactants (in particular those having high hydrophobic character) [30] show a tendency for premicellar aggregation. Compounds 1-4b,c showed a maximum in a Λ vs. C 0.5 plot (as exemplified by 2b, Figure 2, c).…”

“…[18,26b,28,31] As an example, for 2b (Figure 2, c), this maximum in the Λ vs. C 0.5 plot occured at 0.906 m, while the cmc for this surfactant was nearly twice that value at 1.71 m. The formation of premicellar aggregates [28] was also evidenced by a slight curvature towards the κ axis in the κ vs. C plot in the low concentration range for 2b at approximately 0.16 m (see Figure 2, b). We found a minimum in the Λ vs. C 0.5 plot (Figure 2, c) at 0.149 m, which agrees well with the discontinuity in the κ vs. C plot (0.149 m vs. 0.161 m).…”

Synthesis and properties of cationic surfactants with tuned hydrophylicity

“…This was shown by Zana [28] in a study on gemini ammonium surfactants. In general this behaviour was recently found mostly for gemini surfactants, since they behave like more hydrophobic compounds [6,25,29]. Besides, studies on the formation of ion pairs in water and alcohols showed that the ion pairs have high tendency to form when the whole molecule hydrophobicity is growing [30,31], i.e.…”

“…For single chain N-dodecylpyridinium surfactants of this series, both chlorides (a) and bromides (b), a larger increase of the hydrophobicity is required to observe premicellar aggregation. This was found to occur for gemini ammonium surfactants [28], gemini pyridinium surfactants [26] and glucocationic surfactants [29].…”

Synthesis, Physicochemical Characterization, and Interaction with DNA of Long‐Alkyl‐Chain Gemini Pyridinium Surfactants

“…This phenomenon has been already reported in the literature. [48,57,58,74,75] Rosen et al tentatively introduced the CMCc/CMCsr atio to describe the extent of the difference of the CMC determined by different methods. [74] Analogously,wereported this parameter in Table 1.…”