Kagan and Soai win 2026 chemistry Nobel for selecting mirror-image molecules

The 7 October award

The Royal Swedish Academy of Sciences cited the pair "for the discovery of non-linear effects and autocatalysis in asymmetric organic synthesis."

Kagan is an emeritus professor at Université Paris-Sud in Orsay, France, and Soai works in the applied chemistry department at the Tokyo University of Science. The Associated Press gives their ages as 95 and 76. Each takes half of the 12 million kronor. The chemistry prize has now been awarded 118 times; accounts of the total number of laureates differ, with one report putting it at 232 and another at 202.

Kagan graduated from the Sorbonne and took his PhD at the Collège de France. Soai received his PhD from the University of Tokyo in 1979 and did a postdoc at the University of North Carolina.

Why mirror molecules matter

Chiral molecules exist as mirror-image forms, and living organisms mostly use one of them, a property called homochirality. Standard laboratory reactions usually produce a 50-50 mix of both. Drugmakers want the mirror form that treats a disease, not one that makes the symptoms worse, the AP reported. Kagan's non-linear effects let chemists obtain a higher excess of one mirror image than previously thought possible. Soai's autocatalytic reaction went further and produced only one mirror form. Rigoberto Hernandez, president of the American Chemical Society, said: "The medicines we have today would not be possible without this chemistry."

One mirror image of carvone smells of mint and the other of caraway. DNA twists to the right, and human proteins are built mostly from left-handed blocks.

The methods reach past medicine. Peter Somfai, a member of the Nobel Committee for Chemistry, was asked whether any particular drug was developed with the work. "It might be difficult to say that this drug, or that drug, was developed using this," he said. "I would say all of them, because we use this as a tool." Kagan's discovery has changed how chemists develop reactions for pharmaceuticals, flavours, scents and new materials, and the techniques also help manufacturers make safer agricultural chemicals. Soai said chirality in amino acids is essential to the formation of DNA, and therefore to life as we know it.

The science behind the prize

Kagan's 1986 work showed that non-linear effects could push a reaction toward one mirror form. Soai designed a self-amplifying reaction in 1995, and by 2003 he had one that produced only a single mirror image. In autocatalysis, a product of the reaction acts as its own catalyst. The Nobel announcement called the Soai reaction "one of the most spectacular chemical experiments ever conducted." Heiner Linke, chair of the Nobel Committee for Chemistry, said the laureates solved a century-old mystery of how homochirality can emerge spontaneously. The committee described the feat as one never previously achieved by anyone "other than life itself."

Hernandez compared molecular handedness to a couple dancing. "You need to have just the right fit and relative orientation," he said. Molecules that take one orientation keep it for a long time, which matters for how they pair up and align.

Soai told the committee: "This is not the final answer," and said the field should move forward to understand life. He was out shopping near his home when the call came, and called it "one of the most exciting days in my life."

What happens next

The chemistry prize is presented in Stockholm, where the award ceremony is held on 19 December, the anniversary of Alfred Nobel's death. Oslo hosts the peace prize ceremony. The 2026 winners were announced between 5 and 12 October.