Acyclic Analogues of Purine Nucleosides with Dimethylaminoethyl and Dimethylaminoethoxyalkyl Side Chains: Preparation, One- and Two-dimensional 1H- and 13C-NMR Studies

The novel acyclic analogues of purine nucleosides containing 6-N- [2-(dimethylamino)ethyl] and 9-(2-hydroxyalkyl) substituents (6, 7), or 9-[2-(2-(dimethylamino)ethoxy)alkyl] substituent and 6-amino group, free (5) or transformed into pyrrolo moiety (11, 12), were prepared by reaction of protected 9-(2-hydroxyalkyl)adenines with 2-(dimethylamino)ethyl chloride hydrochloride. The substitution site in the purine ring was determined by 1H- and 13C-NMR, using chemical and substituent induced shifts, H-H and C-H coupling constants and connectivities in two-dimensional homo- and hetero- nuclear correlation spectra.