Descriptors

Numerical descriptors

Number of atoms (atoms)

Add or remove hydrogens to count total or heavy atoms SMARTS: *

Number of bonds (bonds)

Add or remove hydrogens to count total or bonds between heavy atoms SMARTS: *~*

Number of Hydrogen Bond Donors (JoelLib) (HBD)

SMARTS: [!#6;!H0]

Number of Hydrogen Bond Acceptors 1 (JoelLib) (HBA1)

Identification of Biological Activity Profiles Using Substructural Analysis and Genetic Algorithms – Gillet, Willett and Bradshaw, U. of Sheffield and Glaxo Wellcome. Presented at Random & Rational: Drug Discovery via Rational Design and Combinitorial Chemistry, Strategic Research Institute, Princeton NJ, Sept. 1995 SMARTS: [$([!#6;+0]);!$([F,Cl,Br,I]);!$([o,s,nX3]);!$([Nv5,Pv5,Sv4,Sv6])]

Number of Hydrogen Bond Acceptors 2 (JoelLib) (HBA2)

SMARTS: [$([$([#8,#16]);!$(*=N~O);!$(*~N=O);X1,X2]),$([#7;v3;!$([nH]);!$(*(-a)-a)])]

Number of Fluorine Atoms (nF)

SMARTS: F

octanol/water partition coefficient (logP)

Datafile: logp.txt

Molecular Weight filter (MW)

Number of triple bonds (tbonds)

SMARTS: *#*

molar refractivity (MR)

Datafile: mr.txt

Number of aromatic bonds (abonds)

SMARTS: *:*

Number of single bonds (sbonds)

SMARTS: *-*

Number of double bonds (dbonds)

SMARTS: *=*

topological polar surface area (TPSA)

Datafile: psa.txt

Rotatable bonds filter (rotors)

Melting point (MP)

This is a melting point descriptor developed by Andy Lang. For details see: http://onschallenge.wikispaces.com/MeltingPointModel011 Datafile: mpC.txt

Textual descriptors

Canonical SMILES (cansmi)

Canonical SMILES without isotopes or stereo (cansmiNS)

IUPAC InChI identifier (InChI)

InChIKey (InChIKey)

Chemical formula (formula)

For comparing a molecule’s title (title)

Descriptors for filtering

Lipinski Rule of Five (L5)

HBD<5 HBA1<10 MW<500 logP<5

SMARTS filter (smarts)

SMARTS filter (s)