BRESLOW AWARDED PRIESTLEY MEDAL ACS's highest honor University's Ronald ι

R onald Breslow, S. L. Mitchill Profes­sor of Chemistry and University Pro­fessor at Columbia University, will

receive the 1999 Priestley Medal. The medal, given annually for distinguished service to chemistry, is the American Chemical Society's highest honor. Bres­low, an organic chemist, was selected last week by the ACS Board of Directors dur­ing the ACS national meeting in Dallas.

Breslow's research is characterized in part by its breadth. He and his students have designed, synthesized, and explored the properties of molecules ranging from three-membered aromatic rings that push the definitions of aromaticity to complex organic systems that begin to imitate the chemical properties of enzymes.

Breslow, 67, has made contributions to chemistry outside the laboratory as well. Among other posts, he was chair­man of the chemistry division of the Na­tional Academy of Sciences from 1974 to 1977; chairman-elect and chairman of the chemistry section of the American Association for the Advancement of Sci­ence from 1987 to 1989; and ACS presi­dent-elect, president, and immediate past-president from 1995 to 1997. In 1996, he wrote a widely acclaimed book for the general public, "Chemistry Today and To­morrow: The Central, Useful, and Creative Science."

"It's a terrific honor to be selected for this award," Breslow tells C&EN. "Be­cause I have been on the ACS Board of Directors, I have some idea of the ex­tremely high quality of the people who are nominated." The award, he says, rec­ognizes the work of his many students and postdocs as well as himself. "I have been helped by the people who were working with me, many of whom have gone on to major scientific careers and awards of their own."

The common thread throughout his research, Breslow says, has been an inter­est "in creating new molecules that didn't exist before that have interesting properties." Sometimes the interest is primarily theoretical, as in the cyclopro-

)ill go to Columbia reslow in 1999 penyl cation, the simplest possible aro­matic ring, which was first prepared by Breslow's group in 1957. Work on this and similar molecules, particularly the re­lated ketone cyclopropenone, has con­firmed and extended theoretical under­standing of what it means for a molecule to be aromatic.

A very different set of molecules whose interesting properties have attracted Bres­low's energies are the catalytic cyclodex-trins. These compounds combine catalyt­ic functional groups with the hydropho­bic binding capabilities of cyclodextrin to give chemically synthesized structures that have been dubbed "artificial enzymes." These systems model several kinds of en­zyme behavior, such as functional group cooperation in operations like proton transfer, exquisite selectivity toward par­ticular substrates or products, or the abili­ty to increase reaction rates as much as 14 million times.

Breslow also has investigated other ar­eas of biomimetic chemistry—a term he coined—particularly the way enzymes use geometric constraints to promote selec­tive reactions that would not otherwise occur. His group has designed molecules

Breslow: creating new molecules

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I to serve as templates to direct reactions such as the functionalization or epoxida-tion of steroids at specific locations.

Molecules that may be valuable in can­cer treatment are another area of Bres­low's research. For the past 20 years, his group has been studying compounds called cytodifferentiating agents. Instead of kill­ing cancer cells, these compounds reestab­lish the processes of cell differentiation and maturation that are arrested in cancer cells. Breslow and his students have shown that linking these compounds to form dimers greatly increases their effectiveness.

Chemistry professor Frank H. West-heimer of Harvard University, a recipient of the Priestley Medal in 1988, says Bres­low's artificial enzymes have helped dem­onstrate "that enzyme catalysis is simply very smart chemistry. They have brought us a long way toward the day—which hasn't quite arrived yet—when we can synthesize model compounds that will function as well as enzymes do."

Of all Breslow's research accomplish­ments, the work that Westheimer "likes best" is some of Breslow's earliest: use of nuclear magnetic resonance spectroscopy to determine the mechanism of action of the coenzyme thiamine, also known as vi­tamin B-l. The work, published in 1957, was both highly imaginative and one of the earliest applications of NMR to mecha­nistic enzymology, Westheimer notes.

Breslow received his undergraduate and graduate training at Harvard, receiv­ing a Ph.D. degree in 1955 under the di­rection of legendary organic chemist Robert Burns Woodward. After a year of postdoctoral work at the University of Cambridge in England, he joined the fac­ulty at Columbia in 1956 as an instructor in chemistry. He became a full professor in 1962, and one of only eight University Professors in 1992.

Breslow is a member of the National Academy of Sciences and the American Academy of Arts & Sciences. Among his many other awards have been ACS's Award in Pure Chemistry in 1966, the James Flack Norris Award in Physical Or­ganic Chemistry in 1980, and the Arthur C. Cope Award in 1987; the National Academy of Sciences Award in Chemistry in 1989; and the U.S. National Medal of Science in 1991. Earlier this year, Chemi­cal & Engineering News named him as one of the Top 75 contributors to the chemical enterprise in the past 75 years. He will receive the Priestley Medal at the ACS national meeting in Anaheim, Calif., in March 1999.

Rebecca Rawls

APRIL 6, 1998 C&EN 11

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