Molecule Tutorials - Herong's Tutorial Examples - v1.26, by Herong Yang
InChIKey - InChI Hash String
This section provides a quick introduction of InChI Key, which is generated from hash values of the InChI string.
InChIKey - InChIKey is a condensed version of the InChI string of a chemical substance, developed under the auspices of IUPAC (International Union of Pure and Applied Chemistry).
Technically, an InChIKey is 27-character long. It consists of three parts separated by hyphens, of 14, 10 and one character(s), in the format of XXXXXXXXXXXXXX-YYYYYYYYFV-P, where:
Theoretically, InChIKey is not unique for each chemical substance. But the likelihood of duplicates is very very small.
For a given molecule, the InChI key can be generated through a set of rules, which are not so easy to follow. So you should use some software tools to help you, like the free "InChI Software" provided at inchi-trust.org/downloads/.
Open Babel can also be used to generate the InChI string for any given molecule.
Here is a list of InChI Keys of some molecules.
Common InChI Name Key ------ ------ Alcohol LFQSCWFLJHTTHZ-UHFFFAOYSA-N Aspirin BSYNRYMUTXBXSQ-UHFFFAOYSA-N Caffeine RYYVLZVUVIJVGH-UHFFFAOYSA-N Oxygen Salt Soda Sugar Water ...
You can use https://pubchem.ncbi.nlm.nih.gov to find the InChI Key of a given molecule.
Table of Contents
►Molecule Names and Identifications
InChI (International Chemical Identifier)
Nucleobase, Nucleoside, Nucleotide, DNA and RNA
ChEMBL Database - European Molecular Biology Laboratory
PubChem Database - National Library of Medicine
INSDC (International Nucleotide Sequence Database Collaboration)
HGNC (HUGO Gene Nomenclature Committee)