Henri Kagan and Kenso Soai Reveal How Molecular Chirality Emerges

By solving the mysteries of chirality, Henri Kagan and Kenso Soai developed a way to design chemical reactions that produce more of the desired version of a molecule.

Solving a Century-Old Chemistry Mystery

Heiner Linke, chairman of the Nobel Committee for Chemistry, explained that Henri Kagan and Kenso Soai had provided a solution to a more than century-old chemical mystery: how homochirality—the selective production of the correct version of a molecule—can emerge spontaneously.

“The chemistry they developed is amazing,” Linke said.

Discovering How to Control Mirror-Image Molecules

In 1986, Henri Kagan of the University of Paris-Sud discovered a new way to manipulate chemical reactions. His work made it possible to create a very large excess of one of two mirror-image forms of a molecule.

Kenso Soai of Tokyo University of Science took the next step in 1995. A scientific paper was published in Nature., external It described the first chemical reaction in history with the potential to become homochiral—a reaction that produces only the desired version of an organic molecule.

In 2003, Soai finally succeeded in controlling a reaction so that only one of two possible mirror images was formed.

“Aside from life itself, no one has ever achieved this feat,” the Nobel Committee said in a statement.

Why Chirality Matters in Medicine

At a press conference on Wednesday, Soai praised “so many outstanding researchers” working in the field.

Professor Robert Mokaya, president of the Royal Society of Chemistry, said the achievement was a “powerful example of how basic chemistry can underpin solutions to some of the biggest challenges facing society”.

“Different isomers, or versions of a molecule, can have completely different biological and physical effects, which is why they are so important in developing effective drugs to treat all kinds of diseases,” he added.