Catanionic Systems from Conversion of Nucleotides into Nucleo-Lipids

This article focuses on reactions performed in nanostructured environments where the pair of complementary nucleotides, 5¢-AMP and 5¢-UMP, are converted into their amphiphilic derivatives. The synthesis is carried out by using the hydrophobic reactant dodecyl epoxide (DE) dispersed in a micellar solution based on the cationic surfactant cetyltrimethylammoniumbromide (CTAB). Novel nucleo-lipids monomers and CTAB molecules give rise to the spontaneous self-assembly of catanionic supramolecular structures in water, showing typical Maltese crosses in optical microscopy. In the final colloidal suspensions, mono- and dichained derivatives have been identified in the system incubated with 5¢-UMP through LC-QqTOF-MS analysis, whereas only mono-alkylated adducts are found in the analogue reaction with 5¢-AMP. A new di-alkylated 5¢-UMP adduct is obtained from the 1:1 mixture of both complementary nucleotides, in addition to the nucleo-lipids found in separate systems. Time-resolvedDLSmeasurements reveal very different kinetic processes for aggregates’ formation when 5¢-UMP, 5¢-AMP, or their equimolar combination are used in the reaction mixture. This system as a whole represents a potential experimental model where the effect of both intermolecular interactions and self-association processes can be investigated by tuning the type of nucleobases in the reaction mixtures.

This article focuses on reactions performed in nanostructured environments where the pair of complementary nucleotides, 5′-AMP and 5′-UMP, are converted into their amphiphilic derivatives. The synthesis is carried out by using the hydrophobic reactant dodecyl epoxide (DE) dispersed in a micellar solution based on the cationic surfactant cetyltrimethylammoniumbromide (CTAB). Novel nucleo-lipids monomers and CTAB molecules give rise to the spontaneous self-assembly of catanionic supramolecular structures in water, showing typical Maltese crosses in optical microscopy. In the final colloidal suspensions, mono- and dichained derivatives have been identified in the system incubated with 5′-UMP through LC-QqTOF-MS analysis, whereas only mono-alkylated adducts are found in the analogue reaction with 5′-AMP. A new di-alkylated 5′-UMP adduct is obtained from the 1:1 mixture of both complementary nucleotides, in addition to the nucleo-lipids found in separate systems. Time-resolved DLS measurements reveal very different kinetic processes for aggregates' formation when 5′-UMP, 5′-AMP, or their equimolar combination are used in the reaction mixture. This system as a whole represents a potential experimental model where the effect of both intermolecular interactions and self-association processes can be investigated by tuning the type of nucleobases in the reaction mixtures. © 2008 American Chemical Society.