MR, molar refractivities

MLOGP Logarithm of the calculated octanol/water partition coefficient MR Molar refraction... 

Recently, Tichy investigated 41) the dependencies of the steric constants, Es, v, L, Bj, B4, MV (molar volume), [P] (parachor), MR (molar refraction), MW (molecular weight), and % (molecular connectivity index) on lipophilicity, as it is measured by n 42) and f43) constants. The data were treated by factor analysis methods. 

To characterize the substituents (the X block) a set common substituent parameters were compiled from the literature. These parameters were as (Taft inductive parameter), trp (Hammett parameter for para substituents), F and R (Swain-Lupton dual substituent parameters), Es and Esc (Taft steric parameters), van der Waals radius, L, Bv B2, B3, (Verloop sterimol parameters), MR (molar refractivity), and n (Hansch lipophilicity parameter). Data are given in Refs. [1,19] and are not reproduced here. 

MR molar refractivity it hydrophobic substituent constant and Op overall electronic constants for meta- and para-position K and p Swain-Lupton resonance and field constants L Sterimol length parameter B1 and B5 Sterimol B parameters SD Dash-Behera steric density parameter. 

MR (Molar refractive index) from C. Hansch and A. Leo, Suhstituant Constants for Correlation Analysis in Chemistry and Biology, John Wiley, New York, 1979 ... 

Fig. 22.4 Molecular properties can be divided into experimental (subdivided into biological and physicochemical) and in silico (subdivided into structural and substructural) properties, physicochemical and biological properties. Examples of experimental data are IC50 (binding affinity), MIC (antibacterial minimum inhibition concentration), LD50 (lethal dose), Vd (volume of distribution), F% (bioavailability), pKg (ionization constant), log P (partition coefficient from shake flask determination), log kn,(lipophilicity from HPLC measurement), A (hydrogen bond capability), solubility. Examples of calculated properties, either for whole molecule or for substituents or buildings blocks, are MW (molecular weight), MR (molar refractivity), molecular volume, PSA (polar surface area), HA (number of H-bond acceptors), HD (number of H-bond donors), CLOGP (calculated log P values), L (substituent length), B5 (substituent width), cr (Hammett constant), F, R (field and resonance parameters), TT (Hansch constant), f (hydrophobic fragmental constant).

Five substituted benzenes were chosen to create a QSAR. These compounds are listed in Table II along with their corresponding substituent physiochemical parameters pi (logP) and MR (molar refractivity). A QSAR set with real parameter values was used in this study in order to obtain a corresponding set of realistic "actual" pKi values. 

MR = molar refractivity B = class-specific constant parachor = the product of the molar volume and a surface tension term. 

Some electronic, geometric, and topological parameters are taken into consideration for the mathematic modeling, they are Log P (hydrophobic constant), square of Log P, a (Hammett constant), Ej Taft values), MR (molar refractivity), (valence molecular connection index). 

C = molar concentration of a drug CNS = central nervous system MR = molar refractivity P = partition coefficient PLS = partial least squares QSAR = quantitative structure-activity relationships. 

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