DNA undergoes condensation, conformational transitions, aggregation and resolubilization in the presence of polyamines, positively charged organic molecules present in all cells. Under carefully controlled environmental conditions, DNA can also transform to a liquid crystalline state in vitro. We undertook the present work to examine the ability of spermidine, N4-methylspermidine, spermine, N1-...

The isolation of 3,6,9,12-tetraazatetradecane-l,14-diamine (linear isomer of pentaethylene­ hexamine, linpen) from a technical polyamine mixture is described. In methanol, linpen acts as a hexadentate ligand towards cadmium(II). The solid compounds [Cd(linpen)](BPh4)2 (1), [Cd(linpen)](BPh4)2-2DM SO (2) and [Cd(linpen)](BF4)2 (3) have been isolated and character­ ized by elemental analysis, spe...

All atom molecular dynamics simulations with explicit water were done to study the interaction between two parallel double-stranded DNA molecules in the presence of the multivalent counterions putrescine (2+), spermidine (3+), spermine (4+) and cobalt hexamine (3+). The inter-DNA interaction potential is obtained with the umbrella sampling technique. The attractive force is rationalized in term...