Chemists are claiming a major breakthrough that will allow quicker and safer development of new drugs. The Princeton University team says its approach “avoids two perennial issues that plague the manufacturing process”.

First it allows scientists to synthesise molecules without employing toxic

catalysts. And just as important, it avoids the production of potentially dangerous mirror-image versions of drug molecules, called enantiomers.

An enantiomer form is thought to behind the dreadful birth defects caused by thalidomide.

In the vast majority of cases, the Food and Drug Administration now requires that drug companies create only the beneficial enantiomer during the manufacturing process. While this requirement keeps the dangerous mirror-image molecules away from patients, it also places heavy demands on the drug companies.

The Princeton researchers report in the journal Science how, since 2000, they have developed a new family of organic catalysts, substances that speed up chemical reactions, which can be used to produce only beneficial enantiomers. Lead researcher Professor David MacMillan said the development would make drugs both more useful and widely available.

"They will allow access to single enantiomers, and they will do it using cheap, environmentally-friendly small organic molecules as catalysts. It's a double whammy,” he said.

Gregory Fu of the Massachusetts Institute of Technology agreed that the research would probably prove important for the pharmaceutical industry.

"This work adds an important new dimension to efforts to achieve asymmetric catalysis," said Fu, a professor of chemistry. "It will no doubt have a substantial impact on the discovery of new bioactive compounds for the benefit of society."

Dr John Schwab, a chemist at the US National Institute of General Medical

Sciences hailed the development. He said the Princeton team had “discovered new reactions that will streamline the synthesis of compounds that are relevant to human health."

Prof MacMillan added that the discovery was important not only for its imediate industrial applications, but also because of the new research possibilities it opened up. "This is a new type of chemistry that could expand the way people think about making biologically active molecules," he said. "We've found more than a new chemical reaction. It's a common mode of molecule activation that allows a whole group of reactions to take place."

Broadly stated, the discovery will open up new possibilities for working with

ketones and aldehydes, two chemical groups that are found on a large percentage of the substances in which organic chemists are interested.

"They form a big region of the reaction landscape," Prof MacMillan said.