Facial amphiphile

Klaikherd A, Sandanaraj BS, Vutukuri DR, Tha3mmanavan S. Comparison of facially amphiphilic biaryl dendrimers with classical amphiphiUc ones using protein surface recognition as the tool. J Am Chem Soc 2006 128 9231-9237. 

Walker S, et al. Cationic facial amphiphiles a promising class of transfection agents. Proc Natl Acad Sci USA 1996 93 1585-1590. 

The ability of the series to induce beta-galactosidase transgene expression in COS-7 cells was measured and compared with Lipofectin (quaternary ammonium salt lipid). The transfection activity of the bile acid conjugates ranged from low (38%) in product 2c to 1000% in product 4c, as compared to Lipofectin , which was ranked as 100%. The in vitro success of these unusual cationic facial amphiphiles is inspiring for the development of more efficient chemical methods based on tissue/cell targeting enabled by the polar face of the amphiphile. 

Cook, A. G., Baumeister, U., Tschierske, C., Supramolecular dendrimers Unusual mesophases of ionic liquid crystals derived from protonation of DAB dendrimers with facial amphiphilic carboxylic acids. J. Mater. Chem. 2005, 15, 1708-1721. 

Figure 1 Schematic representation of the facially amphiphilic and asymmetric structure of a bile acid, a skeletal structure which can be likened to the body of a turtle.

Fig. 43 Structure of the facial amphiphilic mesogenic side-groups AO and An ...

Although the objective of most absorption enhancers is to avoid direct interaction with the mucosal membrane, cell permeation enhancers use this as a means to increase drug absorption. One form of enhancer currently of interest consists of glycosylated molecules, or facial amphiphiles. It is claimed that these compounds temporarily increase membrane permeability. Molecules are designed to self-assemble in membranes to form transient pores that permit hydrophilic com-poimds to cross the membrane. This technology has considerable potential for absorption enhancement. No adverse effects have been reported to date. ... 

Figure 3.11 Schematic model of a micelle consisting of 12 molecules of the rigid facial amphiphile deoxycholic acid. The polar surface is at the concave inside apolar molecules are solubilized on the outer surface.

The result of the interactions of some copolymer mimics of AMP with model bacterial membranes has been studied via atomistic molecular dynamics simulation (Figure 3.2). The model bacterial membrane expands homogeneously in a lateral manner in the membrane thickness profile compared with the polymer-free system. The individual polymers taken together are released into the bacterial membrane in a phased manner and the simulations propose that the most possible location of the partitioned polymers is near the l-palmitoyl-2-oleoyl-phosphatidylglycerol clusters. The partitioned polymers preferentially adopt facially amphiphilic conformations at the lipid-water interface, although lack intrinsic secondary structures, such as an a-helix or P-sheet, found in naturally occurring AMP [23]. 

Design and Synthesis of Facially Amphiphilic Arylamide Polymers... 

FACIALLY AMPHIPHILIC AND ASYMMETRIC STRUCTURES OF BILE ACIDS... 

Fig. 2 (a) A facial amphiphilic and asymmetric structure of CA compared to turtle (b) arrangements of the host molecules—parallel... 

Walker, S. Sofia. M.J. Kakarla. R. Kogan, N.A. Wierichs. L. Longley, C.B. Broker. K. Axelrod, EI.R. Midha, S. Babu, S. Kahne, D. Cationic facial amphi-philes A promising class of transfection agents. Proc. Natl. Acad. Sci. U.S.A. 1996. 93 (4). 1585-1590. Vandenburg. Y.R. Smith. B.D. Perez-Payan, M.N. Davis, A.P. Non-leaky vesicle fusion and enhanced cell transfection using a cationic facial amphiphile. J. Am. Chem. Soc. 2000. 122 (13). 3252-3253. 

Bhat, S. and Maitra, U. Facially amphiphilic thiol capped gold and silver nanoparticles. Joumal of Chemical Sciences ,120(6), 507-513 (2008). 

---