Synthetic Accessibility: Can Your Docking Hit Ever Be Made?

By BioDockify Computational Research Team · September 4, 2026 · Concepts

Synthetic accessibility scores explained: what the 1-10 SA scale measures, what makes molecules hard to make, Ertl S-score bands, and how to triage unmakeable hits.

Read the complete article with tables, code and references on BioDockify.

Key References

• Ertl P, Schuffenhauer A. Estimation of synthetic accessibility score of drug-like molecules based on molecular complexity and fragment contributions. J Cheminform. 2009;1:8. doi:10.1186/1758-2946-1-8
• Genheden S, Thakkar A, Chadimova V, et al. AiZynthFinder: a fast, robust and flexible open-source software for retrosynthetic planning. J Cheminform. 2020;12:70. doi:10.1186/s13321-020-00472-1
• RDKit documentation: SA Score implementation in the Contrib package, rdkit.org.

Scope & Limitations

Accessibility scores estimate difficulty from structure statistics and precedent, not from an actual synthetic route; a hard score is an invitation to plan a route, not a proof of impossibility