As of tonight,
rdf.openmolecules.net links to the chemistry
DBPedia (1816 chemical compounds), for which I used the SPARQL given in
DBPedia: lookup and autocomplete of chemistry. It's first of several steps to extend rdf.openmolecules.net to link up various chemistry database. The below figure shows the current state, where the green nodes are fully RDF-ied:

Drugs are still missing, but will add those too, and since not all entries had InChIs, SMILES were converted using
CDK 1.1.5.