QSAR Studies of 2-Phenylindole Derivatives Using Physicochemical Parameters of Substituents

A novel substituent descriptor based on the physicochemical parameters about the electronic,hydrophobic and steric properties of substituents is used to describe the chemical structures of 2-phenylindole derivatives.The variables are reduced using stepwise multiple regression(SMR) method for the training set,and the statistical results indicate that the correlation coefficient square in the multiple linear regression and cross validation using leave one out(LOO) is 0.900 and 0.662,respectively.To validate the predictive power of resulting models,external validation are performed with R~2_(ext) and Q~2_(ext) values of(0.896 6) and(0.897 4),respectively.The models obtained also shows that the substituents on nitrogen atom of the 1-position of the indole ring have more relative binding affinities.But introduction of substituents with strong electronic effects in 1 and 3 positions of the indole ring and the structure with hydroxy group at in the 4′ position of 2-phenyl ring may decrease the binding affinity between the 2-phenylindole derivatives and ligand of estrogen receptor.