Ralph F. Hirschmann Award In Peptide Chemistry

Sponsored by Merck Research Laboratories

Learning in 1983 that scientists had elucidated the structure of the antibiotic vancomycin was a formative moment for Dale L. Boger.

At the time Boger was an assistant professor at the University of Kansas and just a few years into his academic career, having recently earned a Ph.D. in organic chemistry at Harvard University under chemistry professor and Nobel Laureate E. J. Corey.

For Boger, reading about the vancomycin achievement confirmed that the study of cyclic peptides and other natural products was the right course for him. “It was the type of molecule I had wanted to work on as I began my career,” he recalls.

Boger, 59, clearly chose correctly, because he went on to become one of the leading lights in organic chemistry. Lester A. Mitscher, a professor of medicinal chemistry at the University of Kansas School of Pharmacy, says Boger “has an avid following among medicinal chemists because of the variety, quality, insight, and creativity of his research on peptides and peptidelike molecules.”

After six years at the University of Kansas, Boger moved to Purdue University. In 1991 he joined the faculty of Scripps Research Institute, La Jolla, Calif., where today he is Richard & Alice Cramer Professor of Chemistry and chair of the department of chemistry.

Among the more than 80 natural products Boger and coworkers have prepared by total synthesis over the years, vancomycin holds a special place. In 1983, actually synthesizing the molecule was out of the question for Boger’s small group—or anyone else for that matter. But science advanced, and in the late 1990s Boger’s Scripps team became one of three groups to achieve the total synthesis of vancomycin.

Boger continued to work with vancomycin to reach what is arguably his most important accomplishment. Vancomycin is the antibiotic of last resort for hard-to-treat infections, but bacteria have developed resistance to it as well. In a series of advances over the past decade, Boger’s group identified the source of the resistance as an electrostatic destabilization of binding between drug and bug. The team then developed a vancomycin analog that reinstated some of the binding to resistant bacteria, though it wasn’t very effective against vancomycin-sensitive bacteria.

Last year his group followed up with the synthesis of a new vancomycin analog in which a single atom is modified to counter a single-atom change in the bacteria’s cell wall. This slightly altered vancomycin has full binding affinity for the resistant bacteria and, more important, binds fully to the original bacteria as well. In coming years Boger hopes to develop the analog into a drug that a pharmaceutical company will test in the clinic.

Boger is eager for a drug that helps people fight antibiotic-resistant infections, but he also sees a broader lesson in his group’s work with vancomycin. “It’s a testament to the field of organic synthesis that molecules of that complexity can not only be made via total synthesis but can be changed systematically and explored,” he says. “That’s really what my career has been about.”

Boger will present the award address before the ACS Division of Organic Chemistry.