The 2026 Nobel Prize in Chemistry was awarded to Henri Kagan and Kenso Soai for the discovery of chemical reactions leading to homochirality. Chemists conducting experiments with chemical reactions often observed the existence of two molecules that were mirror images of each other, present in equal proportions within the test tube.
The existence of these mirror-image forms is known as chirality, a term derived from the Greek word *cheir*, meaning "hand." These chiral molecules are described as having either a "right-handed" or "left-handed" configuration.
However, chemists have long sought to produce only the specific mirror-image form (homochirality) required for a given reaction. The discoveries made by Kagan and Soai demonstrated how chemical reactions could be steered to produce homochirality—a capability of immense importance in modern chemical synthesis.
This is particularly significant for the pharmaceutical industry, as many drugs exist in two mirror-image forms: one provides the desired therapeutic effect, while the other may be less effective or cause harmful side effects.
The most notorious case involved the morning-sickness drug Thalidomide in the 1950s. One mirror-image form of Thalidomide relieved nausea, whereas the other caused birth defects in developing fetuses.
Kagan and Soai's discoveries now underpin fundamental chemical reactions used in drug production worldwide; consequently, they were awarded the 2026 Nobel Prize in Chemistry and received a share of the 12 million Swedish krona prize money (approximately RM 4.91 million).
