Lipophilicity Fields An Enhancement of Three-Dimensional Quantitative Structure-Activity Relationships

Computed Lipophilicity Fields An Enhancement of Three-Dimensional Quantitative Structure-Activity Relationships 

When added to CoMFA, the MLP is calculated by Eq. [33] in the same 3D grid as the steric and electrostatic fields. However, the inclusion of MLP in CoMFA is not straightforward because of the composite nature of lipophilicity, which as discussed earlier contains a hydrophobic component and polar terms. In contrast to 2D-QSAR, where the correlation between explanatory variables is easy to assess with a correlation matrix, the correlation between CoMFA signals associated with each molecular field is far from evident. At present, a systematic comparison of all CoMFA models generated by all possible combinations of molecular fields is the only reliable means of detecting correlations between CoMFA results.  

Some of the methods presented in this chapter form the basis of computer programs available as stand-alone programs or as parts of a molecular modeling package. Because we do not have experience in all the available programs, a qualitative comparison of these tools would certainly be partial and biased. Thus, we compile in this section the most widely used programs, taking into account that their principal features were discussed above. 

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