Regioselective synthesis of 1,3,5-13C3 and 2,4-13C2-labeled 2-deoxyribonolactones
P J Hatala1, J Kallmerten, P N Borer
1Department of Chemistry, Syracuse University, NY 13244-4100, USA.
Abstract:
The synthesis of 1,3,5-13C3- and 2,4-13C2-labeled 5-O-bromobenzyl-2-deoxyribonolactones 2, precursors to 13C-enriched nucleoside phosphoramidites for solid-phase synthesis of DNA oligonucletides, is described. An equimolar combination of these two multiply labeled lactones affords a "population-labeled" mixture of isotopomers which exhibits an approximately 50-fold increase in the sensitivity of 13C-NMR compared to natural abundance measurements. The 13C-13C 2-bond and 4-bond coupling constants are reported for the lactones; all are <2Hz, confirming that this labeling scheme should be especially useful for NMR-relaxation measurements.
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