chap1

• Organic Medicinal Chemistry is the practice devoted to the discovery and development of new drugs
• A receptor is a substance that a drug needs to interact with to elicit a pharmacological response, with 90% being proteins, and some being nucleic acids and lipids
• An agonist is a drug that has both affinity and intrinsic activity
• Intrinsic activity is the ability of a drug to exert a pharmacologic action
• An allosteric site is a site other than the binding site
• Absorption is the transfer of a drug from its site of administration to the systemic circulation or bloodstream
• Factors that influence absorption include:

  • Chemical structure
  • Variation in particle size
  • Nature of the crystal form (Amorphous > Crystalline)
  • Type of tablet coating
  • Blood flow to the absorption site
  • Total surface area available for absorption
  • Contact time at the absorption surface
• Bioavailability is the fraction of administered drug that reaches the systemic circulation in a chemically unchanged form
• A drug is an agent intended for use in the diagnosis, mitigation, treatment, cure, or prevention of disease in humans or other animals
• An antagonist is a drug that only has affinity
• The four fundamental pathways of drug pharmacokinetics are:

  • Absorption
  • Distribution
  • Metabolism
  • Excretion
• Metabolism converts drugs into polar, water-soluble products that are readily excretable
• Plasma protein binding serves as a reservoir and may limit access to certain body compartments, prolonging drug duration of action
• The first-pass effect involves drugs being metabolized by hepatic enzymes to inactive chemicals before absorption, mainly occurring with orally and rectally administered drugs
• Enterohepatic recirculation involves drugs emptied via the bile duct into the small intestine being reabsorbed back into the systemic circulation
• Affinity refers to the ability of a drug to bind to the receptor
• Distribution is the process by which a drug leaves the bloodstream and enters the interstitium or cells of the tissues
• Prodrugs are compounds that are inactive in their native form but are easily metabolized to the active agent
• Excretion is the main route of drug and metabolite excretion, mainly through the kidney for low molecular weight and polar drugs
• Other types of excretion include biliary/fecal, breastmilk, and sweat for high molecular weight and lipophilic drugs