NMR SPECTROSCOPIC PROPERTIES (H-1 AT 500 MHZ) OF DEUTERATED-ASTERISK RIBONUCLEOTIDE-DIMERS APU-ASTERISK, GPC-ASTERISK, PARTIALLY DEUTERATED 2'-DEOXYRIBONUCLEOTIDE-DIMERS D(TPA-ASTERISK), D(APT-ASTERISK), D(GPC-ASTERISK) AND THEIR COMPARISON WITH NATURAL COUNTERPARTS (H-1-NMR WINDOW)

Pure 1'#,2',3',4'#,5',5''-H-2(6)-ribonucleoside derivatives 10-14, 1'#,2',2'',3',4'#,5',5''-H-2(7)-2'-deoxynucleoside blocks 15-18 and their natural-abundance counterparts were used to assemble partially deuterated ribonucleotide-dimers (* indicates deuteration at 1'#,2',3',4'#,5',5 (H-2(6))): ApU* 21, GpC* 22 and partially deuterated 2'-deoxyribonucleotide-dimers d(TpA*) 23, d(ApT*) 25, d(GpC*) 26 (* indicates deuteration at 1'#,2',2'',3',4'#,5',5''(H-2(7))) according to the procedure described by Foldesi et al. (Tetrahedron, in press). These five partially deuterated oligonucleotide were subsequently compared with their corresponding natural-abundance counterparts by 500 MHz H-1-NMR spectroscopy to evaluate the actual NMR simplifications achieved in the non-deuterated part (H-1-NMR window) as a result of specific deuterium incorporation. Detailed one-dimensional H-1-NMR (500 MHz), two-dimensional correlation spectra (DQF-COSY and TOCSY) and deuterium isotope effect on the chemical shifts of oligonucleotides have been presented.