A blockbuster synthesis for undergraduates

Esomeprazole (1) (Nexium) is an antiulcer drug developed by AstraZeneca. With global annual sales of $5.2 billion in 2007, it is one of the world's 'blockbuster' drugs.  

Esomeprazole works by selectively inhibiting an enzyme that is responsible for producing acid in the stomach. The reduction of gastric acid helps to heal ulcers. These are sores or raw areas in the stomach and upper part of the small intestine caused by infection with a bacterium or by long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin or ibuprofen. Launched in 2000, esomeprazole was the first enantiomerically pure proton pump inhibitor  to enter the market (Box 1).