Chemistry, Nobel Prize goes to Kagan and Soai: they solved the riddle of homochiriality. What is it?

The 2026 Nobel Prize in Chemistry has been awarded to Frenchman Henri Kagan and Japanese scientist Kenso Soai for their discovery of the nonlinear effect of autocatalysis in organic synthesis.

In its citation, the Swedish Academy explains the importance of the two scientists' work: "Some molecules, such as amino acids, exist in two variants that are mirror images of each other. However, living organisms contain only one of these two mirror images. How this chemical asymmetry could have arisen has long remained a mystery to chemists. Henri B. Kagan and Kenso Soai received the 2026 Nobel Prize in Chemistry for discovering a solution to this riddle."

The chemistry of life—the Academy continues—is defined by scientists as "homochiral," a term derived from the Greek words meaning "same" and "hand." Just like hands, all amino acids exist in two mirror-image variants, but only one of them is present in the proteins of our cells; the other is rarely found in nature. For a long time, chemists wondered how homochirality could arise. When they began experimenting with chemical reactions capable of generating two mirror-image molecules, they always obtained equal proportions of both in their test tubes. However, the chemists' goal was to produce only one of these mirror-image forms, since when developing molecules intended to interact with living organisms—as in the case of drugs—only one of the two variants produces the desired effect.

"The 2026 Nobel Prize in Chemistry," the Academy concludes, "recognizes discoveries that have enabled chemists to guide chemical reactions capable of leading to homochirality."

(Unioneonline)