Quaterthiophene-dinucleotide conjugates (5')TA(3')-t4-(3')AT(5'), (5')AA(3')- t4-(3')AA(5'), and (TT3')-T-5'-t4-(TT5')-T-3' (TA: thymidine-adenosine, AA: adenosine-adenosine, TT: thymidine-thymidine) were synthesized and analyzed by a combination of spectroscopy and microscopy, electrical characterization, and theoretical calculations. Circular dichroism (CD) experiments demonstrated a transfer of chirality from the dinucleotides to quaterthiophene at high ionic strength and in cast films. The films were photoluminescent and electroactive. CD and photoluminescence spectra and current density/voltage plots (measured under dynamic vacuum) displayed significant variation on changing the dinucleotide scaffold. Molecular mechanics and molecular dynamics calculations indicated that the conformation and packing modes of the conjugates are the result of a balance between intra- and intermolecular nucleobase-thiophene stacking interactions and intramolecular hydrogen bonding between the nucleobases.
Water-Soluble, Electroactive, and Photolumines cent Quaterthiophene-Dinucleotide Conjugates.
G Brancolini;M Melucci;A Venturini;NCamaioni;
2008
Abstract
Quaterthiophene-dinucleotide conjugates (5')TA(3')-t4-(3')AT(5'), (5')AA(3')- t4-(3')AA(5'), and (TT3')-T-5'-t4-(TT5')-T-3' (TA: thymidine-adenosine, AA: adenosine-adenosine, TT: thymidine-thymidine) were synthesized and analyzed by a combination of spectroscopy and microscopy, electrical characterization, and theoretical calculations. Circular dichroism (CD) experiments demonstrated a transfer of chirality from the dinucleotides to quaterthiophene at high ionic strength and in cast films. The films were photoluminescent and electroactive. CD and photoluminescence spectra and current density/voltage plots (measured under dynamic vacuum) displayed significant variation on changing the dinucleotide scaffold. Molecular mechanics and molecular dynamics calculations indicated that the conformation and packing modes of the conjugates are the result of a balance between intra- and intermolecular nucleobase-thiophene stacking interactions and intramolecular hydrogen bonding between the nucleobases.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.