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NEW! Online Log P calculator.

Type in your molecule (.hin or .pdb file format) and learn its octanol-water partition coefficient. octanol-water partition coefficient. The Log P value is directly related to the solvation free energy solvation free energy of a substance in the two respective solutes. For dissolvable substances Log P depends also on dissociation constant. dissociation constant.

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Molecule file*

*) Acceptable file formats: .hin, .sdf, .mol2, .pdb


Comparison of the experimental Log P values and those calculated by Quantum 3.2.

The figure above demonstrates the correlation between experimental and Quantum 3.2 calculated Log P for over 900 organic molecules (actually drugs from The Drug Bank database). Root mean squared error is 0.7 LogP units, correlation coefficint r=0.97. No calculated points were removed.

A partition coefficient is a measure of differential solubility of a compound in two solvents (water and octanol). The octanol-water partition coefficient is a measure of the hydrophobicity and hydrophilicity of a substance. In the context of drug-like substances, hydrophobicity is related to absorption, bioavailability, hydrophobic drug-receptor interactions, metabolism and toxicity.

Related terms: Profile ADME Properties of compounds, chemicals' physical properties profiling

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