Washington: A new voyage into “chemical space” – occupied by substances that could become useful in everyday life – has concluded that barely one tenth of 1 percent of the potential medicines that could be made, have been synthesized.
The report estimates that the actual number of these so-called “small molecules” could be 1 novemdecillion (that’s 1 with 60 zeroes), 1 million billion billion billion billion billion billion, which is more than some estimates of the number of stars in the universe.
Jean-Louis Reymond and Mahendra Awale explained that small molecules, which are able to cross cell walls and interact with biological molecules in the body, are prime targets for scientists who develop new medicines.
Most existing medications are small molecules. The researchers focused on the “chemical space” inhabited by all of the small molecules that could possibly exist according to the laws of physics and chemistry.
Researchers have identified millions of these compounds.
Reymond and Awale estimate that the molecules synthesized and tested as potential drugs so far represent less than 0.1 percent of chemical space.
To aid researchers looking for new ways to prevent and treat disease, they set out to find the best ways to search for new small molecules.
The researchers discuss several ways of getting a handle on chemical space, including by the size, shape and makeup of molecules.
They show how computers can help researchers efficiently narrow a search for a new drug candidate.
Computer modeling of chemical interactions can help researchers find a handful of promising molecules to synthesize and test in the lab.
“Small molecule drugs are essential to the success of modern medicine,” the authors noted, and suggested that their methods may be particularly useful for finding new pharmaceuticals that target the central nervous system.
The report appears in the journal ACS Chemical Neuroscience.