PubChem provides
information on the biological activities of small molecules.
It is a component of NIH's
Molecular LibrariesRoadmap
Initiative.
PubChem is organized as three linked databases: PubChem
Substance, PubChem Compound, and PubChem BioAssay. PubChem
also provides a fast chemical structure similarity search
tool. There are links to information on biological properties
from PubChem chemical structure records. Links to PubChem's
bioassay database present the results of biological screening.