At Chemspace, we are willing to provide our users with various tools and services to simplify the selection of the compounds from our database. Among the tools, we have fast online chemical search, custom library preparation, compound sets, – to name a few.

Heavy fragments are one of two Chemspace element-focused libraries.
They are often used to determine/prove the interaction of the molecule with the target protein with a help of X-ray crystallography. Compounds in this set contain one Bromine or one Iodine atom and are free of PAINS and toxic moieties. Apart from this, we limited the number of Chlorine atoms to less or equal to one.

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