The IUPAC International Chemical Identifier (InChI) is a character string generated by computer algorithms (developed by IUPAC) to facilitate the electronic treatment of chemical structures. InChIs are unique to the chemical structures they describe, making chemicals and chemistry machine-readable and discoverable. A simple analogy is that InChI is the bar-code for chemistry and chemical structures.
The most recent version 1.04, released by InChI Trust in September 2011, includes the ability to generate an InChIKey—a condensed 25-character representation of the InChI string. This compact representation of InChI codes significantly expands the use of InChI encoding for structure specification and search, particularly over the Internet.
For more information on the IUPAC International Chemical Identifier (InChI), protocol documentation, source code, trademarks, and licensing conditions, visit the InChI Trust website at www.inchi-trust.org or the IUPAC website at www.iupac.org/inchi.
How can I obtain ACD/Labs InChI implementation?
InChI tools (including InChI-to-structure and vice versa) are currently included in ACD/ChemSketch Freeware and commercial ACD/Labs products.
How can I populate my databases with InChI codes or InChIKeys?
All ACD/Labs database products allow generation of InChIs and InChIKeys both manually and through auto-calculation during structure update to a database. We do not offer any free batch software that allows generation of InChI identifiers. Users of our commercial ACD/Name Batch software modules, however, have access to such capabilities (version 9.0 and later), in addition to batch IUPAC and Index name generation, as well as Name-to-Structure functionality.