Scientists Henri Kagan and Kenso Soai won the 2026 Nobel Prize in Chemistry for solving a long-standing riddle of how to form a single ​molecular mirror image, a discovery hugely important for pharmaceutical manufacturing, the award-giving body said on Wednesday.

“This is ‌the most exciting day in my life, I am very glad to share this prize with professor Henri Kagan,” Soai said, speaking by phone to the Nobel Prize press conference, adding he had been out shopping when receiving the news.

Soai is Japanese, and Kagan French.

The chemistry Nobel, always the ​third prize to be awarded during Nobel week, followed those for medicine and physics announced on Monday and Tuesday.

“So this year’s ​prize is about foundational chemistry,” said Heiner Linke, chair of the Nobel Committee for Chemistry.

Many of the molecules essential to life exist in two forms that are mirror images of each other, like left and right hands, ​he said. Yet living organisms almost exclusively use only one version, a phenomenon known as “homochirality” – from the Greek word for hand – ​that has puzzled chemists for more than a century.

This year’s prize was awarded for discoveries that showed how chemical reactions can be driven to favour a single molecular mirror image, work that has been key for chemists who design reactions for the manufacture of pharmaceuticals.

“Many of the drug molecules ​occur in two variants that are each other’s non-identical mirror image: one has the therapeutic effect, while the other can cause ​unnecessary and sometimes harmful side effects,” the Nobel Foundation said.

Prizes Established in Will of Swedish Inventor

Established in the will of Swedish inventor and ‌businessman Alfred Nobel, the prizes for achievements in science, literature and peace have been awarded since 1901, with a few interruptions mostly due to the world wars.

Nobel, a chemist by trade, amassed huge wealth in the 19th century from inventions primarily tied to warfare, most notably dynamite. The economics prize is a later addition funded by the Swedish central bank.

I am speaking on behalf of all children here in Tuvalu of our home, our culture, our families, our ocean and our way of life.

Sometimes overshadowed by more famous laureates in ​the fields of physics, literature and ​peace, the chemistry awards have still recognised many influential discoveries such as nuclear fission and genetic sequencing techniques.

Last year’s chemistry award went to scientists Susumu Kitagawa, Richard Robson and Omar Yaghi for the development of so-called metal–organic ​frameworks, molecular constructions that can help tackle challenges such as climate change and lack of fresh ​water.

The laureates will ⁠receive their medals from Sweden’s King Carl XVI Gustaf at a ceremony in Stockholm on December 10, the anniversary of Alfred Nobel’s death. The awards are followed by a lavish banquet at Stockholm City Hall.

They also share 12 million Swedish crowns ($1.2 million), as well as the ​fame of winning arguably the world’s most prestigious science award.

The peace prize, the only ​Nobel not presented in Sweden, is awarded separately in Oslo.