Compatibility of functional groups in K ow ‐based QSARs: Application to nitro compounds

Nitro compounds are particularly difficult to handle in simple K ow ‐based QSARs, owing to differences in their lipid‐phase activity coefficients. These differences can be corrected, in part, through inclusion of a term in octanol solubility. A procedure for identifying potentially incompatible groups in a given QSAR is suggested. The quality of a QSAR is best if the interactions of the functional groups involved with octanol fall within a narrow range. These interactions are easily calculated by the UNIFAC method.