The phase I reactions of drug metabolism include the following except:

Biotransformation reactions can be classified into:  Nonsynthetic/Phase 1/Functionalization reactions:  A  functional group (- OH, -COOH, -CHO, H2, - SH) is generated or exposed- metabolite may be active or inactive.  Synthetic / Conjugation / Phase lI reactions:  An endogenous radical is conjugated to the drug- metabolite is mostly inactive; except few drugs, e.g. glucuronide conjugate of morphine and sulfate conjugate of minoxidil are active. Certain drugs already have functional groups and are directly conjugated, while others undergo a phase I reaction first followed by a phase II reaction.