LogP – partition coefficient between lipid membranes and water
The main advantage of Quantum’s software is the quality of the underlying physical models. Most of the competing approaches use different kinds of fragment based descriptors to calculate the molecular properties from known properties of similar compounds (QSAR). Such models that rely heavily on the additivity of molecular properties are often overparametrized and lack direct physical justification. As a result, the prediction power of the models may be very good for structures similar to those used in the training set and may not be sufficient for absolutely novel compounds. Quantum’s software derives the molecular properties from first principles based on direct models using advanced quantum mechanical analysis of molecular interactions and thermodynamics.
pKa – the negative log to base 10 of the acid dissociation constant;
LogBB – blood–brain barrier permeation;
Lipinski’s Rule of Five, an evaluation of druglikeness.
Mean square deviation between calculated and experimental values is 0.7 Log P units. That is of the same order of accuracy as the currently used experimental techniques for determining LogP!
The figure demonstrates calculated Log P values plotted against their experimental ones for over 900 organic molecules (actually drugs from The Drug Bank database). The calculation showed excellent correlation with experimental values: R2 = 0.94.
The Ligands can be supplied in one of the commonly used chemical file formats such as .hin, .pdb, .sdf, .mol2. For LogD calculation pKa value is necessary. If its experimental value is unavailable, you can order our pKa calculation service first to predict these values and then to calculate LogD.
The output data includes LogP and LogD in logarithmic units and estimation of compliance of the drugs with Lipinski’s rule of 5.