Overview

Interface

Structure Search

Text Search

Results

Summary

Overview

ChemSpider is a free online chemical database that has been serving the chemistry community since 2007. It provides a truly vast collection of molecular structures and associated properties, and includes crowdsourcing features for adding data, and improving its quality and reliability.

There are many ways to search ChemSpider, the most direct method being to enter a search term on the main website. The website is optimised for all device form factors (desktop/laptop/mobile), but when it comes to drawing a chemical structure to use for searching the database, the sketching tools are not available for mobile devices.

The Royal Society of Chemistry, owner of ChemSpider, commissioned Molecular Materials Informatics to construct an iOS app, to make structure searching on a mobile device as simple as possible. The resulting app, ChemSpider Mobile, is available to download for free on the iTunes AppStore. The app has a very straightforward design layout, and provides structure drawing capabilities via the embedded version of the powerful MMDSLib structure editor.

Interface

The ChemSpider Mobile app has three tab panels, which are shown along the bottom of the screen:

The Structure and Text panels are used to setup these two types of search operations, while the Results panel is used to display the list of hits from the most recent search.

Structure Search

The structure search panel shows the current molecular structure, and additional search parameters:

The current structure can be modified by activating the New, Edit or Recent buttons. There are presently two types of structure searches that can be performed: Exact and Skeleton. An exact search attempts to match the drawn structure precisely, i.e. atoms, bonds, charge, stereochemistry, isotope, etc., are all required to complete the match, and a result will typically contain one hit, or none at all. A skeleton search, on the other hand, matches the core sigma framework only, and so often results in multiple hits. This is an effective way to search for tautomers, stereomers and materials with different nuclear isotopes.

To modify the current structure, use the Edit button to bring up the embedded MMDS structure editor:

Once the editing is complete, either Accept or Reject the changes.

To draw a new structure from scratch, use the New button. The editor will be invoked, starting with the option to start with a predefined structure template:

A list of recently used structures is maintained, which can be recalled by activating the Recent button:

Selecting any of these structures will replace the current structure.

Text Search

The text search panel shows a single text entry box, for which a chemical identifier should be provided, typically the name of the molecule:

Results

When a structure or name has been specified, the Search button is used, from either of the panels. It will initiate a request to the ChemSpider online database, and when the request is complete, a list of results will be shown, with a structure and name for each.

An exact structure search for aspirin shows a single result:

A skeleton structure search for aspirin shows multiple results, including the conjugate base form, and isomerically enriched substances:

For more information on any of the search results, double-tap on an entry, or select and tap the Open in Browser button. This will launch the mobile browser and direct it to the ChemSpider page, which provides a wealth of information for the molecule:

Summary

The ChemSpider Mobile app makes searching the ChemSpider online database from an iPhone, iPod or iPad both simple and convenient. It is the easiest and most effective way to search by structure on a mobile device. Once results are obtained, detailed information is provided via the standard ChemSpider web page, which provides all of the available chemical information.

See Also

Mobile Molecular DataSheet (iOS), Products