Synthesis of new 3,20-bispolyaminosteroid squalamine analogues and evaluation of their antimicrobial activities.

3,20-Amino- and polyaminosteroid analogues of squalamine and trodusquemine were synthesized involving a stereoselective titanium reductive amination reaction in high chemical yields in numerous cases. These derivatives were evaluated for their in vitro antimicrobial properties against references and clinical bacterial strains exhibiting minimum inhibitory concentrations of 2.5-40 μg/mL. The mechanism of action of these derivatives was determined using bioluminescence for ATP efflux measurements and fluorescence methods for membrane depolarization assays.