2001 Noble Prize Winners in Chemistry
2001 Noble Prize Winners in Chemistry
Two Americans and a Japanese were awarded this year's Nobel Prize in Chemistry for developing more efficient chemical reactions to produce many medicines, including L-dopa, the standard treatment for Parkinson's disease. Dr. William S. Knowles, 84, of St. Louis, who retired from the Monsanto Company in 1986, and Dr. Ryoji Noyori, 63, director of the Research Center for Materials Science at Nagoya University in Japan, shared half of the $950,000 award. Dr. K. Barry Sharpless, 60, a professor of chemistry at the Scripps Research Institute in La Jolla, Calif., received the other half. Dr. Eric N. Jacobsen, a professor of chemistry at Harvard University, said the winners' work "changed the field of chemistry."
The three scientists created catalysts that can selectively produce just one of two versions of a molecule, an essential requirement for the production of many drugs. Catalysts shepherd together other chemicals and increase the efficiency of reactions but remain unchanged themselves.
Dr. Knowles, a pioneer in the field in the late 1960's, said he was overwhelmed by the honor because his work dates so far back. Most molecules come in two forms, identical in structure except that they are mirror images of each other, just as the left hand is the mirror image of the right. While they look alike, the two forms can have very different properties and sharply different effects on the body. For example, one version of the molecule limonene smells of lemons; its mirror image smells of oranges.
Sometimes the differences are catastrophic. In the drug thalidomide, one of the two forms eased nausea in pregnant women; the mirror image, which was not removed from the drug, caused limb deformities in thousands of infants born in Europe and Canada in the 1960's.At that time, the chemical reactions used to manufacture drugs created equal amounts of the two mirror forms. The only way to produce a pure batch of one form was to separate it from the mirror image, a process that was difficult, costly and wasteful.
At least as far back as the 1950's, chemists knew that some catalysts would produce more of one mirror image than the other, but the disparity was not large. "The principle was known, but it was not at all useful," said Dr. Ernest L. Eliel, an emeritus professor of chemistry at the University of North Carolina.
Dr. Knowles, a senior chemist at Monsanto, decided to try...