Esters have a wide range of uses, from giving perfumes and colognes their fragrances, to preventing diseases like scurvy. Vitamin C, that scurvy preventing antioxidant, is derived from carboxylic acids, a class of organic compounds we’ve already learned a lot about! In this episode of Crash Course Organic Chemistry, we’ll look at four different carboxylic acid derivatives and their reactivities, react them with nucleophiles, and learn some hydrolysis reaction mechanisms that we can use in our synthesis of penicillin!