Pyrimidine derivatives represent an extensive class of organic compounds that contain in their structure a six-membered heterocycle with two nitrogen atoms at positions 1 and 3. Substances of this group have a wide range of pharmacological activity, which makes it possible to consider the pyrimidine core as a promising scaffold for the development of new biologically active compounds. The article provides an analysis of the literature data of pyrimidine derivatives used in medical practice. For example, there are substances with antiviral, psychotropic, antimicrobial, antitumor, antifungal, antiparasitic and anabolic activity. Based on the structure-activity relationship of pyrimidine structures of active drugs, as well as other compounds that are considered candidates for the development of new drugs, it is possible to search for and design compounds with the desired types of pharmacological activity. Thus, a systematic analysis of pyrimidine derivatives from a pharmacological point of view can serve as a basis for further search for new highly effective and safe medicines.