Alongside names and CAS numbers, structure-derived identifiers help match a material to authoritative records. This primer explains InChI and InChIKey.
InChI
The IUPAC International Chemical Identifier (InChI) is a text string generated from a molecule’s structure. Because it is derived from structure, it provides a standardized, machine-readable way to describe a compound.
InChIKey
The InChIKey is a fixed-length hashed version of the InChI, convenient for database searching and matching. Searching an InChIKey in a database such as PubChem returns the corresponding compound record.
Finding the authoritative values
For a given compound, obtain the canonical InChI and InChIKey from the authoritative database record (for Phenibut, PubChem CID 14113) rather than a secondary transcription. See Phenibut identifiers and the chemical reference.
For Research Use Only. Not for human or animal consumption. Nothing here is medical advice, a health claim, or usage guidance. No statement has been evaluated by the U.S. FDA. See our Disclaimer.