Therefore, some records in PubChem can persist with outdated (or incorrect) data. To help identify such cases, we are introducing a “legacy” indication for contributors and their records. Please note that this does not mean that data identified as “legacy” is without value.
This might be a trivial question but, would this be the case were certain compounds are not found on some databases but can be found on PubChem? Sooyah
While the InChI representation is normally too complex for a human to decode, it is impossible for even a computer to extract the chemical structure from the InChIKey. therefore, it is important that the InChI repre-sentation is also included in any database.
In instances were chemical structures can't be determined with the provided InChI or InChIKey, are there any tips for searching with an InChI?
these additional data, coupled with the additional metadata recorded in the SDF format, makes this file format ideal
In what instances is MDL ideal and/or when would you prefer MDL over SDF?
a key advantage of the Molfile and SDF formats is the inclusion of geomet-ric information regarding the spatial arrangement of atoms in three-dimen-sional space.
You talk of advantages of using both MDL and SDF formats, are there any disadvantages that would make you utilize other formats?
TheMolecular Structure Encoding System, MOSES, fromMolecular Networks (Erlangen, Germany) is a laterdevelopment from Gasteiger’s team.
What features does MOSES have or how does it address the issue delocalization of electrons between more then two atoms?
The chemical formula is straightforward enough, but the connectivity and hydrogen sections require some explanation. The connectivity layer describes chains and branches –for example in the above Propene example, atom 1 is bonded to atom 3, which is bonded to atom 2. In the final example, we have branching, as represented by paren
This explanation further down makes sense, considering that " different implementations interpret SMILES differently", especially for compounds that have the same chemical formula. I was wondering as to how you would get to the right InChI key, starting from a chemical formula.