Patent ID: 6175004
Filing Date: 2001-01-16
Classification: C07H

Abstract:
A process for preparing an oligonucleotide comprising a nucleoside with a 2,6-disubstituted purine heterocycle having formula (I) ##STR5##whereinR.sub.1, R.sub.2, R.sub.3 and R.sub.4 are, independently, H or a unsubstituted or substituted hydrocarbyl group having from 1 to about 30 carbon atoms, or R.sub.1 and R.sub.2 form a 5 to 13 membered ring or ring system optionally incorporating additional heteroatoms selected from N, O and S, or R.sub.3 and R.sub.4 form a 5 to 13 membered ring or ring system optionally incorporating one or more additional heteroatoms selected from N, O and S; comprising:reacting an oligonucleotide comprising a nucleoside with a 2-halo 6-substituted purine heterocycle having formula (II) ##STR6##whereinX is halogen;Y is F, Cl, Br, I, NR.sub.3 R.sub.4, or NR.sub.3 Pg; andPg is a protecting group;with an amine under conditions to convert the 2-halo 6-substituted purine heterocycle of formula (II) to a heterocycle of formula (I).