cluster_mols is a PyMOL plugin that allows the user to quickly select compounds from a virtual screen to be purchased or synthesized.
The most up to date version (recommended) of clustermols is available through BitBucket at: https://bitbucket.org/mpb21/clustermols_py/overview
This plugin has a number of dependencies that are required. And it is currently only supported on Linux and OSX.
Baumgartner, Matthew (2016) IMPROVING RATIONAL DRUG DESIGN BY INCORPORATING NOVEL BIOPHYSICAL INSIGHT. Doctoral Dissertation, University of Pittsburgh.