Traditional Factorization of Lipophilicity Only Valid for Neutral Species

Traditional Factorization of Lipophilicity (Only Valid for Neutral Species) 

Log P factorization (the decomposition of an object into a product of other objects, or factors, which when multiplied together give the original) demonstrates that lipophilicity is governed by the laws of chemistry (see Section 12.1.1) and thus provides a qualitative chemical insight into partitioning data [8]. 

Abraham s equation (Eq. 4) is the most common tool to factorize log (called simply log P in Eq. 4)  

As the solute descriptors (E, S, A, B and V) represent the solute influence on various solute-solvent phase interachons, the regression coefficients e, s, a, h and V correspond to the complementary effect of the solvent phases on these interactions. As an example, consider the product aA in Eq. (4). Since A is the H-bond acidity of the solute, a is the H-bond basicity of the system. In other words, the intermolecular forces discussed in Sections 12.1.1.2 and 12.1.1.3 are present in all Abraham s log P factorization equations, with the exception of those interactions involving ions. This is the reason why Abraham s equahons are valid for neutral species only. 

As previously mentioned the regression coefficients c, s, a, b and v vary with the parhtioning system inveshgated (e.g. a is 0.034 for octanol-water and -3.45 for dodecane-water as reported by ADME Boxes software version 3.5.), whereas E, S, 

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