Felix W. Wehrli

Proton–coupled 13C nuclear magnetic resonance spectra involving 13C–1H spin–spin coupling to hydroxyl-protons, a complementary assignment aid

Two-, three- and four-bond spin–spin coupling between 13C and hydrogen-bonded hydroxy-protons, identified by deuterium exchange, is shown to aid the assignment of 13C n.m.r. spectra in a series of 5-hydroxyflavones and flavonones.

Carbon-13 nuclear magnetic resonance spectral assignments in large molecules with the aid of spin–lattice relaxation data

13 C Spin–lattice relaxation times are used to assign quaternary carbon n.m.r. signals from codeine and brucine.

Carbon-13 and proton magnetic resonance study of the structure and conformation of a new germacranolide sesquiterpene dilactone

The structure of melampodin B, a new sesquiterpene dilactone isolated from Melampodium leucanthum, has been elucidated on the basis of physical properties, predominantly 13C and 1H n.m.r. data.

Angular dependence of two-bond coupling constant 2JPNC in the NN-dimethylaminophosphines

Low-temperature carbon-13 n.m.r. spectra of NN-dimethylaminophosphines show the two-bond coupling constant 2JPNC to be large and positive when the CN bond is cis with respect to the phosphorus lone pair, whilst it becomes small and negative in the trans-conformation.

Long-range deuterium-induced 13C nuclear magnetic resonance isotope shifts for single assignment and determination of deuteriation site in cyclodecanone isotopomers

The incremental 13C chemical shifts observed upon replacement of protons by deuterons in cyclo-decanones give line assignments which are not otherwise obtainable; apart from directly bonded carbon, isotope shifts were detected across 2, 3, 4, 5, and 6 bonds.

Biosynthesis of the antibiotic thermozymocidin. Incorporation of [1-13C]acetate: 13C nuclear magnetic resonance study

A 13C n.m.r. analysis of [1-13C]acetate-derived thermozymocidin confirms the mixed biosynthesis of this antibiotic from serine and an acetogenine.