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Rcpi (version 1.8.0)

extractDrugWHIM: Calculate Holistic Descriptors Described by Todeschini et al.

Description

Calculate Holistic Descriptors Described by Todeschini et al.

Usage

extractDrugWHIM(molecules, silent = TRUE)

Arguments

molecules
Parsed molucule object.
silent
Logical. Whether the calculating process should be shown or not, default is TRUE.

Value

A data frame, each row represents one of the molecules, each column represents one feature. This function returns 17 columns:
  • Wlambda1
  • Wlambda2
  • wlambda3
  • Wnu1
  • Wnu2
  • Wgamma1
  • Wgamma2
  • Wgamma3
  • Weta1
  • Weta2
  • Weta3
  • WT
  • WA
  • WV
  • WK
  • WG
  • WD
Each name will have a suffix of the form .X where X indicates the weighting scheme used. Possible values of X are
  • unity
  • mass
  • volume
  • eneg
  • polar

Details

Holistic descriptors described by Todeschini et al, the descriptors are based on a number of atom weightings. There are six different possible weightings:
  • unit weights
  • atomic masses
  • van der Waals volumes
  • Mulliken atomic electronegativites
  • atomic polarizabilities
  • E-state values described by Kier and Hall

Currently weighting schemes 1, 2, 3, 4 and 5 are implemented. The weight values are taken from Todeschini et al. and as a result 19 elements are considered. For each weighting scheme we can obtain

  • 11 directional WHIM descriptors (lambda1 .. 3, nu1 .. 2, gamma1 .. 3, eta1 .. 3)
  • 6 non-directional WHIM descriptors (T, A, V, K, G, D)

Though Todeschini et al. mentions that for planar molecules only 8 directional WHIM descriptors are required the current code will return all 11.

References

Todeschini, R. and Gramatica, P., New 3D Molecular Descriptors: The WHIM theory and QAR Applications, Persepectives in Drug Discovery and Design, 1998, ?:355-380.

Examples

Run this code

sdf = system.file('sysdata/OptAA3d.sdf', package = 'Rcpi')
mol = readMolFromSDF(sdf)
dat = extractDrugWHIM(mol)
head(dat)

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