Small molecule natural products are valuable in medicine both as pharmaceutical agents and as starting points for development of pharmaceutical agents. The overarching goal of this dissertation is to describe the role of natural products in drug discovery. This thesis describes the role of natural products in medicine, first by providing a historical context, analyzing the entire dataset of FDA-approved small molecule drugs, first by comparing human and veterinary approved small molecules and their physicochemical properties (Chapter 1), and then by looking at all drugs containing sulfur atoms, the most represented element after the canonical carbon, oxygen, and nitrogen (Chapter 2). Chapter 3 outlines a series of reactions that afford the core structure of the blister beetle toxin cantharidin by novel electrocyclizations, providing access to new cantharidin scaffolds including spiro-cantharidins. This approach overcomes challenges in canthraidin, which have existed since the 1930s. Chapter 4 describes a novel de novo method for generating densely substituted phenols and arenes, structures which are highly represented in both natural products and FDA-approved drugs. Chapter 5 describes methods with several novelties for stereoselectively accessing apomorphine and other aporphine natural products, which play an important role in modern medicine. These new strategies represent the most concise stereospecific synthesis of aporphines to date.