The Chemical module is an optional additional module that must be added to a license. It is not a standard module that is included in all subscriptions by default. When included, the molecule search interface is part of the advanced search form. 

The integration of this module in the advanced search screen allows the user to combine molecules searches with any other fields (keywords, classification, date or legal status limitation etc.).

The molecules can be searched in the Title, Abstract, Claims, Description, and/or Images/.mol fields by using a pull down menu on the right hand side.

By default, the system will search the exact structure you typed in the search box but it is also possible to search sub-structures.


Choosing the "sub-structure search" option allows for searching for the molecule with the replacement of any hydrogens with any atoms.

You can also add more molecules to search. From the form you can combine several molecules by using + sign on the left to add more fields.

They can be combined via an AND (both molecules needs to be found in the same document) or an OR (at least one molecules has to be found in the document). Molecules matching each searched molecule will be highlighted in different colors (these colors can be customized by clicking on the colored letters).

Notes regarding coverage and supported names:

  • IUPAC names, common names and trade names are supported (no capital letters), even CAS number (all written forms are indexed by our partner ChemAxon so the search can be viewed as a search in a dictionary of synonyms)
  • Molecules are extracted from CA, FR, DE, IL, EP, WO, US, KR, JP, GB, AU, CN, IN publications
  • Molecules inside additional .mol files are only extracted from 2007 US publications
  • Molecules are extracted from images inside US, WO, EP and JP publications from 2007 
  • Names containing isotopes are not supported yet
  • The search is case sensitive (CO is different from Co), acronyms have to be searched in upper cases
  • Markush molecules can be searched but cannot be found if not clearly exemplified (by name or by structure) 
  • NB: CAS number coverage is not 100%, you can try the IUPAC name if the CAS has not been found.