Protonenresonanzspektroskopie und Steroidstruktur I. Das C‐19‐Methylsignal in Funktion der Substituenten

The proton NMR spectra of 160 known steroids have been measured as 0.1 molar solutions in deutero‐chloroform. It is shown that the influences of the different substituents and double bonds on the position of the C‐19‐methyl‐signal are additive to a high approximation. Most chemical shifts can therefore be predicted with an accuracy of ± 0.01 ppm. A table of the additional chemical shifts as a function of the nature and position of the substituents is given, which permits the calculation of the chemical shift of the 19‐hydrogen atoms of unknown steroids.