Driven by the need to discover new drug leads for the treatment of Alzheimer’s disease, Dos Santos et al. [65] screened the acetylcholinesterase (AChE) inhibitory activity of derivatives of trachyloban-19-oic acid obtained by biotransformation with Syncephalastrum racemosum. The enzymatic oxidation and rearrangement of the parent compound afforded three metabolites with improved biological activity. The gene discussed is ACHE; the disease is Alzheimer disease.