Researchers from the University of Pennsylvania have developed a new process that promises to improve the efficiency with which the pharmaceutical industry develops new medicines and drugs.

The new process will modify the Diels-Alder reaction, a chemical process which the industry relies heavily upon to produce potential drugs.

"Until now the Diels-Alder reaction has normally been conducted with liquid solvents and solutions," said Jeff Winkler, professor of chemistry at the University of Pennsylvania. "That cannot be done in two or three steps; it requires many intermediate processing steps. At every intermediate step you are guaranteed to lose some of what you will need at the end to assemble the final product. So intermediate steps end up reducing the amount of final product you get compared to what you would get if fewer steps were involved. And on top of that, at the end you only get one chemical to be tested for medicinal or another commercially viable properties instead of a few promising variations."

Winkler and his group modified the Diels-Alder reaction to bypass most of the liquid processing. Instead they used solid polymer beads to force some of the intermediate reactions. Solid polymers allowed Winkler and his colleagues to better control the reactions and eliminate some intermediate steps. With the number of steps reduced, the yields went up. The solid-phase technique also produced more variants of the final product for scientists to test for medicinal or other commercially desirable properties.

"We think this is a big step in chemical processing," Winkler noted.

Pharmaceutical companies spend millions of dollars each year developing and researching new drugs, which is reflected in the price consumers pay for medicine. The researchers believe this new development could save the industry costs, and, ultimately, benefit the consumer.

The importance of the Diels-Alder reaction is not limited to the pharmaceutical industry-the plastics and textile industries also rely heavily on Diels-Alder for their products.

Scott Hoyt, a Penn graduate student working under Dr. Winkler's supervision, presented the results of the research at the American Chemical Society's 212th National Meeting in Orlando, Florida on August 27.

Return to Compass Features for September 3, 1996