Cheno-, urso- and deoxycholic acid spermine conjugates: Relative binding affinities for calf thymus DNA

Cationic lipid polyamine amides (cholan-24-amides) have been prepared from chenodeoxycholic (3 alpha,7 alpha-dihydroxy), ursodeoxycholic (3 alpha,7 be ta-dihydroxy), and deoxycholic (3 alpha,12 alpha-dihydroxy) bile acids (5 b eta-cholanes) by acylation of tri-Boc protected spermine. Their relative bi nding affinities for calf thymus DNA were determined using an ethidium brom ide displacement assay. These lipopolyamine amides are synthetic vectors fo r non-viral gene delivery and models for lipoplex formation with respect to lipofection, a key first step in gene therapy. (C) 2000 Elsevier Science L td. All rights reserved.