NOVEL FUNCTIONALIZATION OF THE SUGAR MOIETY OF NUCLEIC-ACIDS FOR MULTIPLE LABELING IN THE MINOR GROOVE

The sugar ring of adenosine was alkylated at the 2'-O- position using N-(5-bromopentyl)phthalimide and the modified nucleoside was chemically incorporated into oligonucleotide diesters, thioates and RNA analogs. The free amino group, available after oligonucleotide deprotection, is useful for site-specific introduction of reporter groups and therapeutic agents at the 2'-position. This novel methodology permits multiple labeling of nucleic acids in the minor groove.