#2314 CHEBI:16425, please update structure

[Anne Morgat]

Hi ChEBI,

Please would you update the structure of 16-epivellosimine (CHEBI:16425) with the attached mol file.
It is the major structure at pH 7.3 according to Marvin 6.2.0.
This compound is already used in approved Rhea reaction.
Thanks for your support
Anne

[Steve Turner]

Hi Anne,

I'm not sure about this one, the Marvin calculator has not altered the protonation state of the molecule, its just moved a couple of the stereobonds, resulting in a change in IUPAC name. So i think the existing structure should not be altered (incidentally, our version of Marvin just removes the 2 explicit hydrogens). The formula and protonation state are unchanged so this should still be OK to use in Rhea.

Cheers,
Steve

[Anne Morgat]

Hi Steve,
The problem seems to be related to the way the bond are displayed.
See attached screenshot (normalized_chebi_16425.png)
Cheers,
Anne

[Anne Morgat]

Dear Steve,
As the current structure of CHEBI:16425 is not recognized as a normalized structure by the Rhea application, please would you replace it by the attached mol file (even it's just a movement of stereo bonds).
Thanks for your understanding
Cheers, Anne

[Steve Turner]

Hi again Anne,

The alterations made by the Rhea calculator do not take into account stereochemistry rules and have hence corrupted the stereochemistry at the bridgehead. As a result of the movement of stereobonds, CHEBI 16425, 16-epivellosimine, has actually been converted by the Rhea calculator to a different compound called (16S,19E)-sarpagan-17-al. The protonation state is unchanged. The fault here lies with the Rhea calculator rather than the CHEBI representation of 16-epivellosimine, hence I am unable to alter the structure in this case.

Cheers,
Steve