(15)N NMR studies of a nitrile-modified nucleoside.
Nitrile-modified molecules have proven to be excellent probes of local environments in biomolecules via both vibrational and fluorescence spectroscopy. The utility of the nitrile group as a spectroscopic probe has been expanded here to (15)N NMR spectroscopy by selective (15)N incorporation. The (15)N NMR chemical shift (δ((15)N)) of the (15)N-labeled 5-cyano-2'-deoxyuridine (C(15)NdU, 1a) was found to change from 153.47 to 143.80 ppm in going from THF-d(8) to D(2)O. A 0.81 ppm downfield shift was measured upon formation of a hydrogen-bond-mediated heterodimer between 2,6-diheptanamidopyridine and a silyl ether analogue of 1a in chloroform, and the small intrinsic temperature dependence of δ((15)N) of C(15)NdU was measured as a 0.38 ppm downfield shift from 298 to 338 K. The experiments were complemented with density functional theory calculations exploring the effect of solvation on the (15)N NMR chemical shift.
Department of Chemistry, Franklin & Marshall College, Lancaster, Pennsylvania 17604-3003, United States.
Anne T
AT
Gillies
Xin Sonia
XS
Gai
Beth L
BL
Buckwalter
Edward E
EE
Fenlon
Scott H
SH
Brewer
D003857:Deoxyuridine / Q000031:analogs & derivatives / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D009570:Nitriles / Q000737:chemistry*; D009587:Nitrogen Isotopes / Q000737:chemistry; D009705:Nucleosides / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013696:Temperature
C448390:5-cyano-2'-deoxyuridine; D009570:Nitriles; D009587:Nitrogen Isotopes; D009705:Nucleosides; D012997:Solvents; D003857:Deoxyuridine