FragMAX offers fragment libraries for screening experiments. These libraries are designed for crystallographic fragment screening and the compounds are characterized by low molecular complexity and high solubility.

Here you will find information about standard libraries available at the facility:

  • Library composition
  • CSV file for new FragMAX project using our standards (Reference name, SMILES)
  • Basic description of the libraries


FragMAXlib is formulated via in-house fragment collection of FragMAX. FragMAXlib is an XFS-focused library, specifically designed for FragMAX operations. The library is in a constant refinement cycle and is periodically updated, depending on the fragment performance in screening experiments, new chemotypes in a commercial chemical space and platform updates. FragMAXlib compounds are selected on the basis of their fragment-likeness and synthetic tractability. Currently, the library has 172 entries.

Num. heavy atoms81811.2
Num. H-bonds acc.152.5
Num. H-bonds don.020.9
Num. rot. bonds031

Frag Xtal Screen

Frag Xtal Screen is a commercially available fragment library. Fragments are formulated in a solid form, allowing to perform screening experiment even if a crystal system does not tolerate organic co-solvents, e.g. DMSO. The library consists of 96 fragment-alike compounds and crystallization additives.



From the F2X-Universal library we made a sub-selection creating a 96 fragment screen that is still maximally diverse and that we provide in ready-to-use plates to the users. So screens can be carried out on-site or in the user’s home lab. This screen has currently been validated with several test cases and showed high hit rates (~20% on average, 6 campaigns). Further campaigns are ongoing.

EU-OPENSCREEN Fragment Library

EU-OPENSCREEN fragment library is composed of 968 fragments with set of low-molecular-weight fragments and ultra-low-molecular-weight called ‘minifrags’. These fragments are derived from the fragment space of EU-OPENSCREEN high-throughput diversity screening library. The FragMAX users have access to these libraries that can be used on-site.