Professor Emeritus Kenzo Soai and others receive Nobel Prize for discovery of asymmetric autocatalytic reactions - Chemistry Prize for second consecutive year

On the 7th, the Royal Swedish Academy of Sciences announced that the 2026 Nobel Prize in Chemistry will be awarded to two people, including Professor Emeritus Kenzo Soai (76) of Tokyo University of Science, who elucidated the mechanism by which only one of organic compounds (enantiomers) is produced in a mirror-like relationship.

The joint recipient of the award is Henri Kagan (95), professor emeritus of Paris-Saclay University (formerly Paris-Sud University) in France. The reason for the award was ``for the discovery of nonlinear effects and autocatalysis in asymmetric organic synthesis.''

Last year, Osaka University's Specially Appointed Professor Shimon Sakaguchi (75) won the Nobel Prize in Physiology or Medicine, and Kyoto University's Special Professor Susumu Kitagawa (75) received the Chemistry Prize, making him the 31st Japanese person to win the Nobel Prize, including those with American citizenship. He is the 10th person to win the Chemistry Prize for the second consecutive year.

Some organic compounds have the same number and type of atoms but have opposite three-dimensional structures, like mirror images. It can be compared to the relationship between right and left hands, but if you combine them without any effort, you will end up with the same amount of right and left hands mixed together.

However, in the natural world, only one species is extremely abundant, and it has been a mystery why such a difference arises. In addition, when synthesizing pharmaceutical products, one compound may become a medicine and the other a poison, so research was being conducted into ways to produce only the desired compound.

In 1986, Kagan succeeded in producing a large amount of one enantiomer. *In 1995, Mr. Gouji discovered a reaction (asymmetric autocatalytic reaction) in which when the left and right enantiomers are reacted so that there is a slight difference, the product acts as a catalyst and one of the isomers proliferates.

The results are expected to lead to the development of new drug synthesis methods and provide clues to the origins of the substances that make up life.

The award ceremony will be held in Stockholm on December 10th. The prize money of 12 million Swedish krona (approximately 190 million yen) will be divided into two equal parts.

◇Brief biography of Kenzo Soai

*Kenso Soai Born in Hiroshima Prefecture in 1950 (from Fuchu-cho, Hiroshima Prefecture). Completed doctoral course at the University of Tokyo in 1979. After working as a postdoctoral researcher at the University of North Carolina at Chapel Hill, he became an assistant professor at the Tokyo University of Science in 1986, a professor in 1991, and a professor emeritus since 2017.

Medal with Purple Ribbon in 2012, Japan Academy Prize in 2015.