Lipophilicity Modulations by Fluorination Correlate with Membrane Partitioning
Zhong Wang, Hannah R. Felstead, Robert I. Troup, Bruno Linclau, Philip T. F. Williamson
Abstract
Abstract Bioactive compounds generally need to cross membranes to arrive at their site of action. The octanol‐water partition coefficient (lipophilicity, log P OW ) has proven to be an excellent proxy for membrane permeability. In modern drug discovery, log P OW and bioactivity are optimized simultaneously, for which fluorination is one of the relevant strategies. The question arises as to which extent the often subtle log P modifications resulting from different aliphatic fluorine‐motif introductions also lead to concomitant membrane permeability changes, given the difference in molecular environment between octanol and (anisotropic) membranes. It was found that for a given compound class, there is excellent correlation between log P OW values with the corresponding membrane molar partitioning coefficients (log K p ); a study enabled by novel solid‐state 19 F NMR MAS methodology using lipid vesicles. Our results show that the factors that cause modulation of octanol‐water partition coefficients similarly affect membrane permeability.