Application of NMR and Mass Spectrometry to the Study of Drug Hydroxylation

Hydroxylation is probably the most common Phase I metabolic pathway for xenobiotics. It is also a pathway readily detectable by MS from the 16 a.m.u. mass shift for the metabolite ions relative to those of the parent compound. However, such information may sometimes be misleading, and MS does not always allow assignment of the site of hydroxylation.