Structure searching in CAS Online using STN Express:
An introductory workshop

Types of structure searches: Substructure search (SSS)

• SSS search retrieves substances which match the query exactly
• SSS search retrieves substances which match the query with substitution allowed at all positions
  • All query rings are isolated or embedded
  • Variable nodes are allowed in the query
  • Variable bonds are allowed in the query
  • Retrieves all substances having the same connection table
    • Unsubstituted substance
    • Substituted substance
    • Stereoisomers of the substance and substituted substance
    • Isotopically labelled substances
    • Radicals
    • Ions
    • Homopolymers
  • Retrieves multi-component substances that contain query as one of the components