Since the entire system is antiaromatic, why are any carbons at all shown as aromatic in the SMILES?
-P. On Thu, Jan 9, 2020 at 3:56 PM Andrew Dalke <da...@dalkescientific.com> wrote: > Hi all, > > Could someone explain the following, which uses the SMILES from > https://en.wikipedia.org/wiki/Acepentalene : > > >>> from rdkit import Chem > >>> Chem.CanonSmiles("C1=CC2=CC=C3C2=C1C=C3") > 'c1cc2ccc3ccc1-c=3-2' > >>> import rdkit > >>> rdkit.__version__ > '2019.09.1' > > I don't understand the aromatic "c" in the fused center of the 3 > 5-membered rings. It's connected by non-aromatic bonds to the rest of the > system. > > This broke some code of mine which expects that every aromatic atom must > have at least two aromatic bonds. I thought that all aromatic atoms had to > be in aromatic rings, and that all aromatic rings had to have aromatic bond. > > (I'm ignoring RDKit's support for aromatic triple bonds in this > description.) > > I searched for "acepentalene" and "antiaromatic" in the issue tracker and > the mailing list but found nothing relevant. > > Cheers, > > Andrew > da...@dalkescientific.com > > > > > _______________________________________________ > Rdkit-discuss mailing list > Rdkit-discuss@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/rdkit-discuss >
_______________________________________________ Rdkit-discuss mailing list Rdkit-discuss@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/rdkit-discuss