Here we describe the reactivity axis in the ZINC15, particularly in the exported subsets available via the tranche browser.
In the discussion below, ZINC12 standard subsets included: A, C, E.
The ZINC12 subsets known as "clean" subsets were just A and C.
The "I" subset was not loaded in ZINC12, and is only available in 2D (and possibly covalent libraries)
The Reactivity Axis
|Class||Nickname||Description||How computed||Examples||internal score|
|A||Anodyne aka no-PAINS||No flags of any kind set||pattern_origin_fk is null||very unlikely to react or cause trouble in any way||0|
|B||Chromophore||little things people complain about: nitros, chromophores, hydroxamates||not sure||chromophores (assay interference), heptanes (entropy), quarts (not permeable), nitros, hydroxamates. last chance to complain before anodyne||5|
|C||ZINC clean aka PAINS-ok||Worst problem is a match with a PAINS with not clear mechanism||pattern_origin_fk =2||many PAINS are simply frequent hitters, and many legitimate bioactives include PAINS. you may well wish to screen them and use PAINS as an annotation, not a filter||10|
|D||Reserved2||Future Use||no matches||example||20|
|E||mildly reactive||mildly electrophilic, nucleophilic group or redox||pattern_type_fk in (1,2)||e.g. aldhydes, imines, thiols, michael acceptors, epoxides||30|
|F||Reserved3||Future Use||no matches||example||40|
|G||reactive||generally electrophile, nucleophile or redox||pattern_type in (3,4)||e.g. thiocyanates, isothiocyanates||50|
|H||Reserved4||Future use||no matches||example||60|
|I||Highly reactive||Too reactive to be considered as non-covalent ligands||pattern_origin=7||typically reagents; could be used for covalent binding. e.g. boronic acids. alpha halo ketones, alkyl halides. Note includes cancer drugs.||70|
other concepts mentioned, must be fit in: chelation, redox, covalent, amphiphilicity
poor derivatizability, optimizability
we never build protomers of H, G, F.
we need to classify pains by assumed mechanism