• Essentials of Pharmaceutical Chemistry • Third edition Donald Cairns • BSc, PhD, CSci, CChem, MRPharmS, MRSC • Associate Head of School of Pharmacy • The Robert Gordon University Aberdeen, UK Contents • Chemistry of acids and bases • Partition coefficient and biopharmacy • Physicochemical properties of drugs • Stereochemistry • Drug metabolism • Volumetric analysis of drugs • Analytical spectroscopy • Stability of drugs and medicines • Kinetics of drug stability What is Pharmaceutical Chemistry? Pharmaceutical chemistry is the study of drugs, and it involves drug development. This includes drug discovery, delivery, absorption, metabolism, and more. . Pharmaceutical chemistry is concerned with the design (drug design) and synthesis of biologically active molecules. The aim is to gain new chemical molecules that could enable the discovery of new pharmaceuticals or optimize already known drug structures, thereby to expand the portfolio of chemical drugs. Chemistry of acids and bases Chemistry is the defining science of pharmacy. To understand anything about a drug; – the synthesis, the determination of its purity, the formulation into a medicine, the dose given, the absorption and distribution around the body, the molecular interaction of drug with its receptor, The metabolism of the drug and, the elimination of drug from the body – requires a thorough and comprehensive understanding of the chemical structure of the drug and how this chemical structure influences the properties and behaviour of the drug in the body. For these reasons, chemistry is the most important of all the scientific disciplines contributing to the understanding of drugs and their actions in the body.