✍ Scribed by Aponte, Maria A. ;Butler, George B.
No coin nor oath required. For personal study only.
A study was conducted of the complementary base pair interactions between various pairs of electron‐donor monomers, electron‐acceptor monomers, homopolymers and alternating copolymers selected from the following group: (1) 9‐(2‐vinyloxyethyl)adenine; (2) 1‐(2‐vinyloxyethyl)thymine; (3) 1‐(2‐vinyloxyethyl)cytosine; (4) 9‐(2‐maleimidoethyl)adenine; (5) 6‐chloro‐9‐(2‐maleimidoethyl)purine; (6) 1‐(2‐maleimidoethyl)thymine; (7) 1‐(2‐maleimidoethyl)cytosine; (8) homopolymer of (4); (9) homopolymer of (6); (10) alternating copolymer of (2) and maleic anhydride; (11) alternating copolymer of (2) and (5); and (12) alternating copolymer of (2) and (4). By ^1^H‐NMR, in CDCL~3~, the base pair interactions between (1) and (2) were shown to be hydrogen bonding, the extent of which was shown by a calculated binding constant, K = 61.81 L/mol. The nature of this interaction was conformed by IR. Neither monomer pairs (1)/(2) nor (4)/(6) exhibited hydrogen bonding in DMSO‐d~6~. However, hydrogen bonding interaction was observed for DMSO‐d~6~ solutions of homopolymers (8) and (9) and for alternating copolymer (12). On the basis of an upfield chemical shift of the 2‐ and 8‐aromatic protons of ademine of (1) in D~2~O, a partial overlap stacking interaction is proposed. No charge‐transfer interactions could be observed by UV between donor‐acceptor monomer pairs.
📜 SIMILAR VOLUMES
Stacking of aromatic amino acids tryptophan (Trp), tyrosine (Tyr), phenylalanine (Phe), and histidine (His) with bases and base pairs of nucleic acids has been studied. Stacking energies of the amino acid-base (or base pair) complexes have been calculated by second-order perturbation theory. Our res