The adoption if InChI is increasing, despite its limitations. But one thing I find greatly missing, is chemical databases supporting access of entries via the appropriate InChI. I know there are resolvers around, but that is different. They do a search, and give me multiple links to individual structures that may match to a certain extend. I am not interested in that in this context.
What I want instead is to be able to deep link to a particular entry in ChemSpider, PubChem, HMDB, or whatever databases using the InChI instead. The only service currently supporting this that I am aware of, is rdf.openmolecules.net. It uses a URI pattern like http://rdf.openmolecules.net/?$INCHI. For example, the entry for methane is http://rdf.openmolecules.net/?InChI=1/CH4/h1H4 and this URI deep links to the entry of methane, rather than a search result list.
So, the core requirement is that the database URI tells me, either: "yes, this is the one and only entry matching 100% this InChI", or "no, I do not have data for this structure".
What other databases support deep linking using the InChI? And what would the URI look like?