July 20, 2020

  • Updated
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Combine Duplicate CAplus and MEDLINE References

This feature will combine the contents of CAplus and MEDLINE records for references which are determined to be duplicates in our data. For these combined documents, the visual indication in a reference result set that will indicate a combined reference is that the database entry in the bibliographic data displays “Database: CAplus and MEDLINE” as shown below.


References that are not deemed to be duplicates will continue to display with a single database as the source.

The Database filter on the Substances result set has changed functionality as well. Previously, the database CAplus and MEDLINE filter options were mutually exclusive. If you selected one of those options, it would filter the results to include references only from the selected database, so the sum of the filter option counts would equal the result count shown at the top of the page.

Now, the filter options are no longer mutually exclusive. Selecting the CAplus or MEDLINE option filters the result set to include references that are combined as well as references from a single database.


On the Reference Detail page for combined references, the “Database Information” section now includes the database information for both databases. The CAplus and MEDLINE contents will be combined as shown below and will be present if available:

  • Concepts contains CAplus concepts.
  • MEDLINE® Medical Subject Headings contains MEDLINE MESH terms.
  • Supplementary Concepts contains MEDLINE supplementary terms
  • Substances contains a deduplicated display of CAplus indexed substances and MEDLINE chemicals.
  • MethodsNow: Analysis contains CAplus MN: A links.
  • Formulations contains CAplus formulations data.
  • Citations contains a deduplicated display of CAplus and MEDLINE citations.


For data such as source and bibliographic information, we will be displaying the CAplus values.

However, the MEDLINE organization name (to include organizations for which the non-first author is affiliated) will continue to be searchable in addition to CAplus subdivisions and countries.

There are two major advantages of the new combined display:

  • Deduplication of the reference result set: In most cases, this will reduce the number of results in the result set, which removes the clutter caused by duplicate references without the loss of the unique content that may be provided by one of the databases.
  • Enhanced result recall: Combining the contents of CAplus and MEDLINE has the additional benefit of being able to take advantage of the unique content that may be provided by each database, which can serve to enhance result recall, particularly while using Boolean operators in the search query.


ChemPlanner – Highlight Stereoselective Steps

Reaction steps in a retrosynthesis plan now include a visual indication that the step is stereoselective. The stereoselective step now has a different icon than non-stereoselective steps as shown below. The stereoselective steps can be theoretical or experimental.


The Steps tab in the collapsible drawer also includes the new icon along with the text “Stereoselective.”


Additionally, there is a Stereochemistry filter in the Alternative Steps window that can be used to filter the alternative steps by Selective or Non-Selective stereochemistry. In the window, each individual alternative step that is stereoselective possesses the text “Stereoselective” as well as the new icon.


These changes to the retrosynthesis display are also reflected in the PDF download.

Export Tagged Properties

Substances property .xlsx downloads now also include the "tagged" properties in addition to the experimental properties for which specific values have been captured. Tagged properties are those properties whose values state "See Full Text" on the Substance Detail page.


Sort References by Publication Date

The References result set page Sort by Publication Year was replaced by Sort by Publication Date, which provides a much more granular sorting capability. The sort now takes advantage of the month, day, and year rather than just the year. There are some references for which we only have a publication year. In those cases, the references sort to the end of the publication year range or the beginning of the publication year range if the references are sorted newest or oldest, respectively.


Update to Reference Excel Download

We have updated the References result Excel download to replace the Publication Year with the Publication Date. Similar to the sort, if we do not have a full publication date, the publication year displays.