Henri Kagan, Kenso Soai win 2026 Nobel Prize in Chemistry for solving molecular ‘mirror image’ mystery
French chemist Henri B. Kagan and Japan’s Kenso Soai have won the 2026 Nobel Prize in Chemistry for discoveries that showed how chemical reactions can produce only one of two mirror-image forms of a molecule - a fundamental feature of the chemistry of life.
The Royal Swedish Academy of Sciences awarded the prize “for the discovery of non-linear effects and autocatalysis in asymmetric organic synthesis.”
Many molecules, including amino acids, can exist in two forms that mirror each other like left and right hands. Yet the proteins in living cells contain only one of these forms, a phenomenon known as homochirality.
For decades, chemists struggled to explain how such asymmetry could arise. Experiments designed to create mirror-image molecules generally produced equal amounts of both.
Kagan made a breakthrough in 1986 when he discovered a way to manipulate chemical reactions that produced a much greater excess of one mirror-image form than previously thought possible.
Soai went further. In 1995, he described a reaction with the potential to become homochiral, and in 2003 demonstrated a reaction that produced only one of the two possible mirror images — something the Nobel committee said had never previously been achieved outside life itself.
Their discoveries have also helped chemists design reactions used to manufacture pharmaceuticals, where only one mirror-image form of a molecule may produce the desired effect.
Kagan, 96, is professor emeritus at Université Paris-Sud. Soai, 76, is professor emeritus at Tokyo University of Science.
The laureates will share the prize of 12 million Swedish kronor.