The Synthesis of Deuterionucleosides

RNA Helical Packing in Solution: NMR Structure of a 30kDa GAAA Tetraloop–Receptor Complex

“…Selective deuteration of the 5 position of uracil used the same procedure described for deuteration of UMP. 50 All NMR samples were between 0.5 mM and 2.0 mM RNA at pH 6.8. Samples used in RDC measurements were partially aligned using the bacteriophage pf1 (ASLA Biotech) in 50 mM phosphate buffer (pH 6.8).…”

“…Integrated NOE peak volumes were calibrated to the average pyrimidine H5-H6 NOE volume, corresponding to a fixed distance of 2.4 Å . NOE distances were also obtained using information from nonexchangeable 2D NOESY at various mixing times (25,50, 100 and 200 ms). These distances grouped into three classes: strong (1.8-3.0 Å ), medium (1.8-4.5 Å ), and weak (3.00-6.00 Å ).…”

Studies on the Stereoselective Synthesis of Deuterated D‐Ribose Derivatives

“…± The importance of the structure ± biological activity relationship of an oligo-DNA and oligo-RNA has been investigated by different physicochemical techniques, amongst which NMR spectroscopy was found to be the most powerful tool as it provides the conformational data under quasi-physiological conditions [1]. Although, with the increasing chain length, the usefulness of NMR spectroscopy becomes restricted, site-specific isotope labeling has been proven to overcome this problem in the recent past (for a review, see [2]). While, the use of 13 C/ 15 N isotopes increases the number of observable resonances [3] [4] [5 ± 7], 2 H labeling of oligonucleotides is based on the primary idea of suppressing part(s) of the 1 H-NMR spectrum [8].…”

“…Partial or complete substitution of 1 H by 2 H in the sugar residue of a nucleoside and incorporating them into an oligomer in a sequence specific manner has helped to solve the above problem as described in −Uppsala NMR Window× concept [9]. Recently, the results have been reported on the chemical synthesis of (5R)-and (5S)-[3',5'-2 H 2 ]nucleosides [9] and [3',4',5',5''-2 H 4 ]nucleosides [10a] for the use in the preperation of nonuniformly labeled DNA and RNA, and in their NMR measurements.…”

“…(4)), and 4.27 (s, HÀC(2)) indicated that photobromination was indeed stereoselective. 2 H was then introduced at C(5) in dry THF with LiEt 3 BD (Aldrich; 1.0m in THF, 2 equiv.) as 2 H source.…”