NEW YORK – 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 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.

Carbon atoms are normally shy about pairing up. The winning approach was to use atoms of the metal palladium kind of like a singles bar, a place where pairs of carbon atoms are jammed together and encouraged to bond. This idea, called palladium-catalyzed cross coupling, was easier to do than previous methods.

Heck published his initial work in 1968 and an improved method in 1972. In 1977, Negishi developed a variant of the palladium approach and two years later Suzuki developed another.

Their methods are widely used in industry and research.

“I don’t think anybody thinks about making a complicated organic compound without considering one of these three reactions,” said Keith Woerpel, a chemistry professor at New York University.

one estimate, they’re the basis for at least 25 percent of all chemical reactions in the pharmaceutical industry, said prize committee member Claes Gustafsson.

That includes the production of the common painkiller naproxen, widely sold as Aleve and other brands, new antibiotics, an asthma drug and a synthetic version of a substance from a marine sponge that might fight cancer. Heck’s work was adapted to make the cancer drug Taxol, steroids and morphine.

In agriculture, the palladium approach is used to make chemicals that protect crops from fungi and other pests. And the electronics industry uses it for coating electronic circuits and as a tool for developing future computer screens that are thinner, said prize committee member Jan-Erling Backvall.

Jeremy Berg, director of the National Institute of General Medical Sciences in Bethesda, Md., said the three did “very fundamental and important work.”

Bonds between carbon atoms “are really the lifeblood of the ability to make organic compounds,” Berg said. “Making the carbon-carbon bond is really sort of the framework. It’s like the framing of a house. You can add on other pieces later on, but the carbon-carbon formation is really a key part of it.”