It's the unexplored regions that could hold molecular solutions to some of the world's most vexing challenges, Beratan said.
To add diversity and explore new regions to the chemical space, Aaron Virshup developed a computer algorithm that built a virtual library of 9 million molecules with compounds representing every region of the small-molecule universe.
"The idea was to start with a simple molecule and make random changes, so you add a carbon, change a double bond to a single bond, add a nitrogen. By doing that over and over again, you can get to any molecule you can think of," Virshup said.
He programed the new algorithm to make small, random chemical changes to the structure of benzene and then to catalogue the new molecules it created based on where they fit into the map of the small-molecule universe. The challenge, Virshup said, came in identifying which new chemical compounds chemists could actually create in a lab.
Virshup sent his early drafts of the algorithm's newly constructed molecules to synthetic chemists who scribbled on them in red ink to show whether they were synthetically unstable or unrealistic. He then turned the criticisms into rules the algorithm had to follow so it would not make those types of compounds again.
"The rules kept us from getting lost in the chemical space," he said.
After ten iterations, the algorithm finally produced 9 million synthesizable molecules representing every region of the small-molecule universe, and it produced a map showing the regions of the chemical space where scientists have not yet synthesized any compounds.
"With the map, we can tell chemists, if you can synthesize a new molecule in this region of space, you have made a new type of compound," Virshup said. "It's an intellectual property issue. If you're in the blank spaces on our small molecule map, you're guaranteed to make something
|Contact: Ashley Yeager|