Nobel Prize in Chemistry Awarded to Kagan and Soai

Synopsis

Scientists Henri B. Kagan and Kenso Soai won the Nobel Prize in chemistry Wednesday for untangling mysterious mirror images in molecules, a discovery that has helped develop countless drugs and transformed modern medicine.

The Research that Earned Them the Prize

Many molecules come in versions that look alike but aren't identical, like right and left hands. For example, one mirror image of the chemical carvone smells like mint, while the other smells like caraway, a spice often used in rye bread.

Even life itself prefers one mirror image over the other. DNA twists to the right, and the proteins in human bodies are made of mostly left-handed building blocks.

Versions of the same molecule can behave differently when interacting with other chemicals. When designing drugs to treat diseases, scientists want to choose which mirror image they get. They want the version of a molecule to treat a cold, not one that will make the sniffles worse.

Kagan, who is from France, and Soai, from Japan, found ways to make chemistry pick a side, designing and manipulating reactions to produce the desired mirror image.

President of the American Chemical Society, Rigoberto Hernandez, said, "The medicines we have today would not be possible without this chemistry."

The Discovery Enabled Most Modern Medicines

Scientists paid tribute to Kagan and Soai's work, which the Nobel committee described as a feat never previously achieved by anyone "other than life itself."

A member of the Nobel Committee for Chemistry, Peter Somfai, said, "It might be difficult to say that this drug, or that drug, was developed using this. I would say all of them, because we use this as a tool; we use this as an understanding of how to develop catalysts and how they function."

In the 1980s, Kagan's work showed there might be a way to design reactions to produce one form of a molecule over the other. Years later, Soai perfected the process. He created the first-ever chemical reaction to efficiently produce only one of a molecule's mirror images, in what's now known as the Soai reaction.

Somfai said, "This is probably the coolest experiment in organic chemistry." In addition to developing better medicines or fragrances, deciphering the mirror images of molecules can help scientists understand the chemical architecture of life, said chemist Holden Thorp, editor-in-chief of the journal Science.

Kagan, 95, is affiliated with the Université Paris-Sud in Orsay, France. Soai, 76, is affiliated with the Tokyo University of Science. The French Academy of Sciences, of which Kagan is a member, congratulated the two scientists and expressed its pride in the prize.

Soai told the committee and journalists by phone, "I'm very excited to receive the very nice news. Of course, this is one of the most exciting days in my life." He said he was shopping near his home when he was reached by the Nobel committee.

More Nobel Prizes Will be Awarded Over the Next Week

The Royal Swedish Academy of Sciences announced the winner in Stockholm. Last year, three scientists won the chemistry Nobel for their development of new molecular structures that can trap vast quantities of gas inside, laying the groundwork to potentially suck greenhouse gases out of the atmosphere or harvest moisture from desert environments.

This year's prizes began with the Nobel for medicine, awarded Monday, October 5, 2026, to three scientists whose work led to a tool that uses light to help unravel how the brain works. The physics award Tuesday recognized a scientist's efforts to demystify a rare group of neutrinos.

The literature prize is set to be awarded Thursday, October 8, 2026. After the Friday, October 9, 2026, peace prize is awarded, the Nobel Memorial Prize in Economic Sciences will be announced Monday, October 12, 2026.

The prize money this year is 12 million Swedish kronor (about $1.2 million), whether for an individual, a small group of laureates, or an organisation.