The model provided suitable predictive performance, affording R2Tr = 0.9984 and RMSETr = 0.0192 for the training set and R2CV = 0.9783 and RMSECV = 0.0748 for the testing set. The experimental and predicted activities (pIC50 values) of the compounds (1 - 11) in the data set are summarized in Supplementary Table S2 and Figure 4(Fig. 4).