Stereospecific assignment of H5' and H5″ in a (5'R)-/(5'S)-deuterium- labeled DNA decamer for(3) J (HH) determination and unambiguous NOE assignments.
The stereoselective deuterium labeling at the 5' methylene protons of the ribose ring recently developed by Kawashima et al. [1995, Tetrahedron Lett., 36, 6699-6700] enabled the assignment of pro-R and pro-S protons at the 5' position. The deuterium-labeled nucleotides, [(5'S)-(2)H]- and [(5'R)-(2)H]-diastereomers, in an approximate ratio of 2:1, were incorporated in the decamer 5'-d(GCATTAATGC)-3'. Thus, both pro-R and pro-S methylene proton signals without geminal coupling appeared in the NOESY and DQF-COSY spectra. Complete stereospecific assignments and simplified spin systems enabled the determination of 15 (3)J coupling constants between H4' and H5'/H5", and the unambiguous assignment of 135 NOESY cross peaks originating from H4'/H5'/H5" resonances.
Kojima
C
C
Institute for Protein Research, Osaka University, Suita, Osaka, 565, Japan.
Kawashima
E
E
Toyama
K
K
Ohshima
K
K
Ishido
Y
Y
Kainosho
M
M
Kyogoku
Y
Y