Computer‐Assisted Prediction of Bioactive Compounds Based on the Hansch‐Fujita Analysis

Computer programs called PREHAC1 and PREHAC2, which aid in the impartial selection of substituents for the synthesis of highly bioactive compounds among congeners based on the Hansch‐Fujita analysis, were developed. The PREHAC1 and 2 programs are for aliphatic and aromatic monosubstituted derivatives and for aromatic disubstituted derivatives, respectively. Thirteen sets of physicochemical parameter values of 408 useful substituents were previously input into a data file as Master Data. PREHAC programs are activated by the input of the coefficients and intercept of the QSAR equation with the corresponding parameter codes, the information on the number of the substituents to be printed out, etc., and then Master Data is searched. Calculated activity values are ranked in descending order and the high‐ranking substituents are printed out according to the specified number. An example is presented to illustrate the programs.