Medicinal chemists around the world have been inspired by nature and have successfully extracted chemicals from plants. Research on enzymatic modifications of naturally occurring compounds has played a critical role in the search for biologically active molecules to treat diseases. This book set explores compounds of interest to researchers and clinicians. It presents a comprehensive analysis about the medicinal chemistry (drug design, structure-activity relationships, permeability data, cytotoxicity, appropriate statistical procedures, molecular modelling studies) of different compounds. Each chapter brings contributions from known scientists explaining experimental results which can be translated into clinical practice. Volume 3 presents (1) a brief overview of botanical and pharmacological properties of alkaloids, (2) a summary of the synthesis of natural morphinans and related alkaloids, (3) caffeine-based compounds for the treatment of neurodegenerative disorders, (4) piperine derivatives, (5) noscapine-based anti-cancer agents, (6) biogenic amines and amino acid derivatives as carbonic anhydrase modulators and (7) antimalarial compounds on quinoline scaffolds. The objective of this book is to fulfil gaps in current knowledge with updated information from recent years. It serves as a guide for academic and professional researchers and clinicians.