We are pleased to introduce version 11.8 of our ChemDoodle 2D software. This update is free for all ChemDoodle subscriptions, Lifetime and Site licenses. Licenses are as little as $19, and we have a free trial available at: https://www.chemdoodle.com/


Some new feature highlights in ChemDoodle 2D v11.8.

Executive Summary

ChemDoodle 2D v11.8 includes significant improvements to many features, including excellent chain replacement nomenclature in IUPAC naming, support for allene/cumulene stereochemistry, improved bezier curve tools, current InChI support and more file options.


  1. Excellent IUPAC naming support for chain replacement nomenclature. There are two new options as well: (1) to enable/disable chain replacement nomenclature (on by default) and (2) to allow a minimum of 2 replacements (3 required by default).
  2. Updated InChI support to the current v1.06. Full support for InChI stereochemistry, including allenes and cumulates.
  3. Stoichiometry tables can now be generated from typed chemical equations, in addition to drawn chemical reactions. Simply select the Reaction>Stoichiometry... menu item with no reaction selected, and a form will appear for you to input the typed chemical equation.
  4. Full support for allene and cumulene stereochemistry, both for odd numbers of bonds (E/Z) and even numbers of bonds (M/P). There is a style to change M/P displays to Ra/Sa instead.
  5. Allene and cumulene coordinates are now properly assigned by the 2D structure cleaning function. Stereochemistry is preserved for these centers.
  6. Double bonds in ring sizes of 7 or smaller are no longer designated stereochemical configurations by default, as designated by the IUPAC Blue Book 2013. You may turn these double bond configurations back on in the Functions panel.
  7. Users now have control over the CIP ligand cutoff length.
  8. Bezier curve editing has been vastly improved. You are now able to change the locations of control points independently of their mirror, but the default behavior is to keep them symmetrical. All micro edits can now be undone and redone. The first intersect point's first anchor will now appear and be editable if the custom shape is closed. Better handling of cases where a bezier curve drawing is cancelled.
  9. Perfect support for bezier curve objects in ChemDraw CDX/CDXML files.
  10. Added support for mmCIF, BinaryCIF and PDBML.
  11. Added option to add PAIR headers to SDF file output in the Files panel.


  1. Corrected issue where stereochemical configurations were not automatically resolving for meso centers.
  2. Fixed the automatic updating of cis/trans stereochemical configurations.
  3. Corrected issue where an implicit hydrogen and explicit hydrogen on the same side of a double bond would not disqualify the stereochemical configuration.
  4. Adjusted the handling of isotopes in the CIP algorithm to match the latest Hanson paper.
  5. Included a check for corrupted bond spacing output from ChemDraw CDX/CDXML files and corrected the values.