cited By 50International audienceTwo new families of cationic lipids were designed and synthesized for gene delivery, namely "lipophosphoramidates" and " lipophosphoguanidines", whose efficiency was noteworthy. The most efficient have an arsonium cation as the polar head, and the unsaturated lipidic tails (e.g. oleyl) gave the better in vivo results (mice lungs). © 2005 American Chemical Society