摘要:
The synthesis of guanidinium-linked cytidyl oligomer (DNG-C-8), a cationic DNA analog, and the corresponding cytidine monomers is described. The DNG monomer synthesis was streamlined to produce a shorter route to the final monomer than previously reported for thymidine and subsequent solid-phase synthesis produced an octameric cytidyl DNG strand. Because octameric deoxyguanosine would be used as the complementary strand in our studies, it was necessary to investigate guanosine self-association. Singular value decomposition was used to mathematically deconvolve the spectral data and confirm the presence of transitions due to DNA-G(8) self-association. Job plots show the binding stoichiometry of DNG-C-8 with DNA-G(8) to be 1: 1. Thermal denaturation studies of the DNG-C-8-DNA-G(8) duplex established a T-m greater than or equal to 90degreesC and a DeltaGdegrees = 13.3 kcal mol(-1), indicating the DNG-C(8)(.)DNA-G(8) duplex is over 1000 times more stable than that of DNA-C(8)(.)DNA-G(8). (C) 2004 Elsevier Ltd. All rights reserved.