NMR AND UV STUDY OF 1,1'-(ALPHA,OMEGA-ALKANEDIYL)BIS[THYMINE] AND 1,1'-(ALPHA,OMEGA-ALKANEDIYL)BIS[URACIL]

Treatment of thymine or uracil with Br(CH2)(n)Br (n = 3-10) in the pre sence of t-BuOK gave 1,1'-(alpha,omega-alkanediyl)bis[thymine] or 1,1' -(alpha,omega-alkanediyl)bis[uracil] together with 1-(omega-bromoalkyl )thymine or 1-(omega-bromoalkyl)uracil. The structures of these produc ts were determined on the basis of the coupling constants between 5- a nd 5-positions of uracil ring on the H-1 NMR spectra. Molecular aggreg ation of the thymine and uracil rings of these compounds in aqueous so lution was studied on the basis of their H-1 NMR and UV spectra. A sta cking interaction of the two thymine rings linked by shorter polymethy lene chains such as trimethylene and tetramenthylene groups was observ ed.