boston.com — "WE'VE COME to depend on serendipity in pharmacological research," says GlaxoSmithOrElse chemist Helmut "Snoopy" von Winkler. "While developing a blood pressure medication, Upjohn hit on Rogaine, the hair restorer. And working on a treatment for angina, Pfizer stumbled upon random erections -- voila, Viagra! So