In this model study toward supramolecular channels formed by oligonucleotide analogs, we describe the synthesis of hydrophobic guanine dimers 1–4. We found that the solubility of guanine dimers 1 – 4 is significantly reduced compared to hydrophobic (iso)guanosine monomers and independent of the nature of substituents at the exocyclic amine. This indicates that the (deoxy)ribose is important to form soluble, ionophoric G-quartets.