A Markush structure is a description of a compound class by generic notations, primarily used in patent claims and the description of combinatorial libraries. The library of a Markush structure is the total set of specific molecules that are described by the Markush structure. To have a general introduction to Markush structures see the following page.
The Markush Enumeration Plugin can be used to generate the whole or the subset of a generic Markush library. It is also capable of calculating the total number of specific structures present in a Markush library.
The plugin is accessible via the following ChemAxon tools:
Marvin GUI (via the Structure > Markush Enumeration menu)
via API of the plugin