Egon Willighagen

About two weeks ago, the ChemConnector blog [reported an InChIKey
collosion](http://www.chemconnector.com/2011/09/01/an-inchikey-collision-is-discovered-and-not-based-on-stereochemistry/)
detected by [Prof.
Goodman](http://www-ucc.ch.cam.ac.uk/researchgroups/goodman_group).
Unlike the previous collision, this one was based solely on the graph
and not on stereochemistry. The two molecules both have the InChIKey
`OCPAUTFLLNMYSX-UHFFFAOYSA-N`{.language-plaintext .highlighter-rouge}:

![](/assets/images/inchikey1.png){style="height:400px"}
![](/assets/images/inchikey2.png){style="height:400px"}

The compounds are really different, the molecular formulas are
C~50~H~102~O and C~57~H~114~O respectively. The SMILESes are
`OC(C)C(C)CC(C)C(C)CCC(C)C(C)CCCC(C)C(C)CC(C)C(C)CCCC(C)C(C)CCC(C)C(C)CC(C)CCCCCCC`{.language-plaintext
.highlighter-rouge} and
`O=C(C)CC(C)C(C)CCC(C)CCC(C)C(C)C(C)C(C)C(C)C(C)C(C)C(C)CC(C)C(C)C(C)CC(C)C(C)C(C)CCCCC(C)C(C)CC(C)C(C)C`{.language-plaintext
.highlighter-rouge}. The IUPAC names are useful to have as
copy/pastables too (e.g. with the
[OPSIN](http://opsin.ch.cam.ac.uk/)-based '[Molecule from IUPAC
name](http://chem-bla-ics.blogspot.com/2011/02/opsin-used-for-bioclipse-wizard.html)'-wizard
in [Bioclipse](http://bioclipse.net/) 2.5, which has been updated to the
latest OPSIN version this week):
3,5,6,9,10,14,15,17,18,22,23,26,27,29-tetradecamethylhexatriacontan-2-ol
and
4,5,8,11,12,13,14,15,16,17,18,20,21,22,24,25,26,31,32,34,35-henicosamethylhexatriacontan-2-one.

I am adding these structures to the [pharmbio.org course
book](http://chem-bla-ics.blogspot.com/2011/03/pharmaceutical-bioinformatics.html)
and the matching Bioclipse plugin this weekend.

#### References


About two weeks ago, the ChemConnector blog reported an InChIKey collosion detected by Prof. Goodman. Unlike the previous collision, this one was based solely on the graph and not on stereochemistry. The two molecules both have the InChIKey OCPAUTFLLNMYSX-UHFFFAOYSA-N: The compounds are really different, the molecular formulas are C

 50

H

 102

O and C

 57

H

 114

O respectively.

Messaggi di Rogue Scholar

InChIKey collision: the DIY copy/pastables