Effective November 7, 2019, a Derwent Markush Resource (DWPIM) release improves your Markush search results in the following areas:
Closed substructure search
Repeating groups
Matching of A, Q, and XX node
Ring lock function
Searching hybrid ring systems
Details are available at: http://www.stn-international.com/fileadmin/be_user/STN/pdf/database_details/DWPIM_Rn_003.pdf
Contact your local service center if you have any questions.