Reactivity axis

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	example	0
B	Reserved1	Future Use	no matches	example	5
C	ZINC clean aka PAINS-ok	Worst problem is a match with a PAINS with not clear mechanism	pattern_origin_fk =2	example	10
D	Reserved2	Future Use	no matches	example	20
E	mildly reactive	mildly electrophilic or nucleophilic group, including PAINS where these mechanisms have been assigned.	pattern_type_fk in (1,2)	aldhydes, thiols, michael acceptors, epoxides	30
F	Reserved3	Future Use	no matches	example	40
G	reactive	electrophile or nucleophile, including PAINS where these mechanisms have been assigned	pattern_type in (3,4)	alpha halo ketones, alkyl halides. Note includes cancer drugs.	50
H	Reserved4	Future use	no matches	example	60
I	Unstable	Highly reactive	pattern_origin=7	typically reagents, but could be used for covalent binding. e.g. boronic acids	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