Table 1

Descriptors of chemical space consisting of sc-PDB-derived ligands and ACD-SC-derived ordinary molecules and corresponding loadings (Varimax normalized) for the first two factors*

Descriptors
Characterization
Factor loadings
Software






1
2


AREA
Total molecular surface area
0.974
0.103
Sybyl
PSA
Polar molecular surface area
0.255
0.892

PV
Polar molecular volume
0.501
0.741

VOL
Total molecular volume
0.991
0.062

MOLWEIGHT
Molecular weight
0.958
0.206

Acceptor
H-bond acceptor counts
0.464
0.799

Donor
H-bond donor counts
0.376
0.817

BondCount
Total bond counts
0.972
0.060

Chiral
Counts of chiral center
0.367
0.617

Hydrophobe
Hydrophobic fragment counts
0.767
-0.417

RingCount
Ring counts
0.686
-0.069

RotBonds
Number of rotatable bonds
0.630
0.428

HeavyAtoms
Number of non-H atoms
0.978
0.149


Carbons
Number of carbons atoms
0.943
-0.228
Perl
Oxygens
Number of oxygen atoms
0.425
0.793

Nitrogens
Number of nitrogen atoms
0.475
0.324

Sulfurs
Number of sulfur atoms
0.141
-0.009

Phosphorus
Number of phosphorus atoms
0.162
0.617

Halides
Number of halide atoms
0.076
-0.170

DoubleBonds
Number of double bonds
0.527
0.378

TripleBonds
Number of triple bonds
-0.009
-0.109


RadOfGyration
Radius of gyration
0.888
0.004
Cerius 2
ShadowXY
Surface area projections
0.967
0.076

ShadowXZ

0.951
0.053

ShadowYZ

0.877
0.093

ShadowXYfrac

-0.610
-0.027

ShadowXZfrac

-0.421
-0.002

ShadowYZfrac

-0.289
0.039

Shadownu

0.268
-0.117

ShadowXlength

0.849
-0.008

ShadowYlength

0.798
0.075

ShadowZlength

0.756
0.059

Density
Density
-0.089
0.354

PMImag
Principal moment of inertia
0.819
0.134

AlogP
Log of the partition coefficient using Ghose and Crippen's method.
0.425
-0.727

AlogP98
Log of the partition coefficient, atom-type value, using latest parameters.
0.365
-0.852

Fh2o
Desolvation free energy for water
-0.479
-0.762

Foct
Desolvation free energy for octanol
-0.578
-0.617

LogP
Log of the partition coefficient.
-0.022
-0.892

MR
Molar refractivity using Hopfinger's method.
0.835
-0.110

MolRef
Molar refractivity using linear additive method based on AlogP atom types
0.986
-0.033

JX
Balaban indices
-0.567
0.027

Kappa1
Kappa topological indices
0.969
0.189

Kappa2

0.926
0.026

Kappa3

0.691
0.033

Kappa1AM

0.958
0.220

Kappa2AM

0.901
0.050

Kappa3AM

0.630
0.046

PHI
Molecular flexibility index
0.800
0.078

SC0
Subgraph topological counts
0.980
0.147

SC1

0.973
0.125

SC2

0.943
0.186

SC3P

0.904
0.141

SC3C

0.749
0.389

SC3CH

0.016
-0.086

CHI0
Kier and Hall Chi connectivity indices
0.974
0.190

CHI1

0.983
0.115

CHI2

0.958
0.210

CHI3P

0.939
0.136

CHI3C

0.655
0.484

CHI3CH

0.015
-0.087

CHIV0

0.990
0.076

CHIV1

0.971
0.120

CHIV2

0.913
0.137

CHIV3P

0.838
0.096

CHIV3C

0.476
0.148

CHIV3CH

0.016
-0.088

Wiener
Wiener topological index
0.854
0.186

logZ
Logarithm of Hosoya topological index
-0.220
-0.131

Zagreb
Zagreb topological index
0.958
0.162


*The first factor explains 52.8% of the variance and the second explains 12.7%. Factors with high loadings (>0.9 for first factors and >0.8 for second factors) are shown in bold.

Ji et al. Genome Biology 2007 8:R176   doi:10.1186/gb-2007-8-8-r176