Bolaamphiphile synthesis

Surfactants, Renewable resources. Carbohydrates, Polyols, Oils, Fats, Cationic emulsifiers, Gemini, Bolaamphiphiles synthesis. Surface propraties. Applications... 

Jorgenson et al. reported [125] the synthesis of bolaamphiphile 46 in which a tetrathiafulvalene (TTF), a substrate currently of importance in fields such as organomagnetism and molecular electronics, was incorporated within the central lipophilic region. Gel formation of 46 (Fig. 20) in either DMF-water or ethanol-water solution was noted which bear similarities with the above findings of Newkome and coworkers. 

Since these arborols (111) are comprised of two hydrophilic groups connected by a hydrophobic linkage, they fit the simple definition of a bolaamphiphile a term derived from bolaform amphiphile, originally introduced in 1951 by Fuoss and EdlesonJ128 In 1984, when Fuhrhop and Mathieu 129 reported the synthesis and self-assembly of several bolaamphiphiles, these two-directional surfactant-like macromolecules represented a simple entrance to the bolaamphiphile field this subject has recently been highlighted1130 and reviewed.1131 ... 

A new family of crown-ether-based bolaamphiphiles, 21, that aggregate into a previously unknown type of bolaamphisome was prepared by Gokel and coworkers [50]. Evidence was presented on vesicle formation from the aqueous suspension of such bolaform amphiphiles. Several reports describing the synthesis of various macrocyclic models related to archael compounds have also appeared in the literature [51]. Fyles et al. prepared a novel series of asymmetric bis-macrocyclic bolaphiles, 22, and evaluated their transport activities in vesicles and planar bilayer membranes [52]. 

Ether linkages in open-chain bolaamphiphiles were obtained in a 20% isolated yield from a,o)-dibromoeicosane with an alcohol in THF containing sodium hydride (Scheme 2.8). The synthesis of macrocyclic tetraethers was unsuccessful. Attempts to reduce macrocyclic lactones with four ester groups via a variety of methods failed. The production of macrocyclic thioacetals from benzaldehyde derivatives and a,to-dithiols was unproblematic and produced quantitative yields (Scheme 2.8). The cyclization of 2,2-thiodiethanol with a,(o-diols in the melt and in the presence of /7-toluenesulfonic acid is an intermediate case. Apolar macrocycles were obtained in 50% yield. 5-(2-hydroxyethyl)thiiranium ions are presumably formed as reactive intermediates during the ether formation steps. The sulphur atom was oxidized to the... 

M. Masuda and T. Shimizu, Synthesis of novel a,co-type 1-glucosamide and galactosamide bolaamphiphiles, J. Carbohydr. Chem., 17 (1998) 405 16. 

Access to unsymmetrical derivatives was envisaged, especially to study symmetrical or dissymmetrical organization of bolas in lipid membranes. They are usually prepared by selective reactions of one functional group of the unprotected symmetrical hydrophobic core, Shimizu and Masuda [68] developed the synthesis of bolaamphiphiles 15a-g containing an oligomethylene chain connected with a sugar at one end and a free carboxylic acid... 

Benvegnu X, LecoUinet G., Girilbot J., Roussel M., Brard M., PlusqueUec D., Novel bolaamphiphiles with saccharidic polar headgroups Synthesis and supramolecular self-assembUes, Polym. Int., 52(4), 2003, 500-506. 

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