New York City ? A method for building complex molecules has paid off by helping to fight cancer, protect crops and make electronic devices — and now it has earned its developers a Nobel Prize.

Three men — two Japanese scientists and an American researcher — designed the technique to bind together carbon atoms, a key step in assembling the skeletons of organic compounds used in medicine, agriculture and electronics.

Their work in the 1960s and 1970s provided “one of the most sophisticated tools available to chemists today (and) vastly improved the possibilities for chemists to create sophisticated chemicals,” the Nobel committee said.

The winners are Richard Heck, 79, a professor emeritus at the University of Delaware, now living in the Philippines; Ei-ichi Negishi, 75, a chemistry professor at Purdue University in West Lafayette, Ind., and Akira Suzuki, 80, a retired professor from Hokkaido University in Sapporo, Japan.