Deuterium Isotope Effects on 13C Chemical Shifts of Enaminones.
نویسندگان
چکیده
منابع مشابه
Deuterium isotope effects on 15N backbone chemical shifts in proteins
Quantum mechanical calculations are presented that predict that one-bond deuterium isotope effects on the (15)N chemical shift of backbone amides of proteins, (1)Delta(15)N(D), are sensitive to backbone conformation and hydrogen bonding. A quantitative empirical model for (1)Delta(15)N(D) including the backbone dihedral angles, Phi and Psi, and the hydrogen bonding geometry is presented for gly...
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Deuterium isotope effects on ¹³C-NMR chemical shifts are investigated in a series of 10-hydroxybenzo[h]quinolines (HBQ's) The OH proton is deuteriated. The isotope effects on ¹³C chemical shifts in these hydrogen bonded systems are rather unusual. The formal four-bond effects are found to be negative, indicating transmission via the hydrogen bond. In addition unusual long-range effects are seen...
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ژورنال
عنوان ژورنال: Acta Chemica Scandinavica
سال: 1997
ISSN: 0904-213X
DOI: 10.3891/acta.chem.scand.51-1016