Henri Kagan and Kenso Soai were recognised for the discovery of non-linear effects and autocatalysis in asymmetric organic synthesis.

Two scientists from France and Japan have won the Nobel Prize in Chemistry for their discoveries that proved to be crucial to how chemists design reactions for the manufacture of pharmaceuticals, flavours, scents and new materials.

Henri Kagan and Kenso Soai were recognised by the Royal Swedish Academy of Sciences (RSAS) for the discovery of non-linear effects and autocatalysis in asymmetric organic synthesis.

The pair’s research is considered foundational to understanding the principles of ‘homochirality’, part of a phenomenon whereby some molecules, such as amino acids, exist as two variants that are each other’s mirror image, but living organisms will only contain one of these images.

The Nobel laureates’ work laid out a path for how to design and initiate certain types of chemical reactions so that greater quantities of a favourable molecule are selectively created at the expense of its naturally occurring mirror image that might be wasteful or harmful in an intended use context.

Kagan is credited with discovering, in the 1980s, a revolutionary new way of manipulating chemical reactions to allow for a greater excess of one of the molecular mirror images to be created than was previously assumed possible.

In 2003, Soai designed and executed the first chemical reaction in which only one of the potential mirror images was formed. The ‘Soai reaction’ is considered “one of the most spectacular chemical experiments ever conducted”, according to RSAS.

“Henri Kagan and Kenso Soai have provided a solution to a chemical mystery that is over a century old: how homochirality can emerge spontaneously,” said Heiner Linke, chair of the Nobel Committee for Chemistry. “The chemical reactions they have developed are spectacular.”

According to RSAS, understanding reaction mechanisms is a fundamental part of organic chemistry, with the rationale that emerges from such activities useful for prediction, control, and design of new and as-yet untested reactions that can address unsolved problems.

“The discoveries awarded with the 2026 Nobel Prize in Chemistry have deepened our appreciation of molecular chirality, with implications that extend well beyond the realms of organic chemistry,” said Peter Somfai, a professor of organic chemistry at Lund University and a member of the awarding committee.

Kagan, born in France in 1930, and Soai, born in Japan in 1950, will share a prize of 12m Swedish kronor (€1.07m).

Earlier this week, the 2026 Nobel Prizes in Physiology or Medicine and in Physics were awarded to scientists from the US, Germany and Belgium.

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