Bioorganic chemistry attempts to broaden the knowledge of PhD candidates related to drug interactions with natural compounds and possibilities of influencing such interactions by structural modifications. The subject bioorganic chemistry comprises two following areas: chemistry of natural compounds (proteins, saccharides, nucleic acids and lipids) and drug development and behavior in the organism (for example, optimization of drug structure, drug behavior in the organism, physico-chemical properties of drugs, and noncovalent drug interactions with natural compounds).