Benzonitrile nitrogen-15 nuclear magnetic resonance chemical shift as a probe of solvent dipolarity

Modeling Amino Acid Side Chains in Proteins: 15N NMR Spectra of Guanidino Groups in Nonpolar Environments

“…This is mainly due to the fact that arginine itself, with three ionizable groups in one molecule, has insufficient solubility in nonpolar solvents for 15 N NMR measurements. In contrast, strong solvent effects on 15 N chemical shifts have extensively been demonstrated for many compounds, − including pyridine 9 and simple alkylamines. , …”

“…This is mainly due to the fact that arginine itself, with three ionizable groups in one molecule, has insufficient solubility in nonpolar solvents for 15 N NMR measurements. In contrast, strong solvent effects on 15 N chemical shifts have extensively been demonstrated for many compounds, [5][6][7][8][9][10][11][12] including pyridine 9 and simple alkylamines. 11,12 On the other hand, vibrational spectra modeling the arginine side chain in various protein environments have recently been measured using alkylguanidinium salts under various solvent conditions.…”

Theoretical analysis of solvent effects on nitrogen NMR chemical shifts in oxazoles and oxadiazoles

“…Especially, the nitrogen magnetic shielding turned out to be very sensitive to a solvent [2]. The solvent effect on the nitrogen nuclear magnetic shielding has been investigated both experimentally [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] and theoretically [20][21][22][23][24][25][26][27][28][29][30][31][32]. In particular, the solvent effects on the 14 N magnetic shielding in 5-and 6-membered hetero-aromatic compounds have been extensively studied experimentally by Witanowski et al [3][4][5][6][7][8][9].…”