RT Book, Section A1 Renslo, Adam A1 Koltun, Dmitry A2 Renslo, Adam SR Print(0) ID 1124842193 T1 The Nature of Bonding in Organic Molecules T2 The Organic Chemistry of Medicinal Agents YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071794213 LK accessbiomedicalscience.mhmedical.com/content.aspx?aid=1124842193 RD 2024/03/28 AB In this chapter, we will review fundamental concepts of chemical structure and bonding in the organic molecules that make up drugs and their biological targets. By “organic,” we mean molecules that are constructed primarily from the element carbon (C). Carbon exhibits striking versatility in its ability to form various different bonding arrangements with other carbon atoms as well as with other biologically relevant elements such as nitrogen (N), oxygen (O), sulfur (S), and phosphorus (P). It is this versatility that allowed carbon-based life to emerge on our planet. Thus, to understand the molecules of life—proteins, lipids, nucleic acids, hormones, etc.—and the drugs that interact with them, we must start with a solid understanding of structure and bonding in organic molecules. In this chapter, we will begin by contrasting the nature of ionic and covalent bonding and will describe the polarization of covalent bonds. We will then dive deeper into the nature of the covalent bond, discussing atomic and molecular orbitals, the “hybridization” of orbitals, and aromaticity. Finally, we will review some important functional groups and organic ring systems that figure prominently in the structures of biological molecules and drugs.