Large OA database of chemical molecule structures

Molecules@gnu-darwin.org is an OA database of "more than 4 million small molecule structure files in pdb format, and molecular graphics representations. About 50 million molecules are still in the pipe ...". (Thanks to Antony Williams.)

See also Williams' comments on the database:

The statement that there are 50 million molecules in total coming suggests that the database is a republication of PubChem and the SDF archives seem to suggest so too ...

At present the database therefore appears to be the PubChem database in PDB format. ...