HYDROLYSIS OF OLIGONUCLEOTIDES CONTAINING 8-SUBSTITUTED PURINE NUCLEOSIDES - A NEW ROUTE FOR PREPARING ABASIC OLIGODEOXYNUCLEOTIDES

2'-Deoxyadenosine substituted at C-8 by a propylthio group was introdu ced into oligodeoxyribonucleotides by solid phase synthesis. Oxidation by potassium persulfate (oxone) occurred selectively on the sulfur co ntaining nucleoside causing a weakening of the glycosidic bond. Subseq uent hydrolytic treatment led to selective removal of the modified bas e and generation of an abasic site. This constitutes a novel and conve nient route for the chemical synthesis of oligodeoxyribonucleotides co ntaining an abasic site at a preselected position in the sequence.