Factorial design strategy in this work refers specifically to a 2n factorial
design. Generally, a miminum of three factors are required to describe the
chemical structure of a lead compound in terms of its electronic, lipophilic
and steric properties. Using the three parameters, pi (lipophilicity),
sigma (electronics), and L (length), a 2n factorial design requires 23 or 8 compounds. One additional compound is included (a central point of the design)
to allow the consideration of interaction terms for a total of nine compounds.
The substituents selected are orthogonally distributed so there is minimal
cross correlation of factors (parameter), this ensures a set of compounds with
properties well spread within the design space selected.
