Specifying Variable Atoms

Instead of requiring a specific atom at a particular site, you can use a variable to specify a generic atom type, such as X for "any halogen", or A for "any atom except hydrogen."

 

  1. Click the Variables    icon.

  2. Click the variable atom type.

 

  Notes:

  • Ak represents any carbon chain. The Ak group cannot be attached to another Ak group, including those within R-groups or repeating groups.

  • Ak only works when placed in a terminal position when searching DCR.

  • Cy represents any ring system of any size or composition, single or fused ring systems. Cy encompasses both Cb and Hy.

  • Cb is a subset of Cy and includes only carbon atoms.

  • Hy is a subset of Cy and includes at least one non-carbon atom.

  • Id is a generic node used to:

    • Show the SRU (Structural Repeating Unit) endpoints.

    • Define an ID molform.

    • Search for incompletely defined substances.

 

  1. Click the atom site on the structure where you want to place the variable.

Learn More

Drawing and Editing Structures

Substructure Queries

Reaction Queries