Selecting the right compounds for screening: use of surface-area parameters.

Polar surface area, total surface area and percentage surface area have been calculated from three-dimensional structures of 88 post-emergence herbicides, 93 pre-emergence herbicides and 237 insecticides. Preferred ranges of values of these parameters were identified. Since the compounds in the training sets are used on a wide variety of species and target sites with various application modes, the parameter ranges are necessarily broad. The utility of the surface-area parameter ranges in selection of compounds for agrochemical screening was compared with the use of ranges of the Lipinski Rule of 5 parameters: molecular mass, calculated log P, number of hydrogen-bond donors and number of hydrogen-bond acceptors. The more computationally intensive surface-area parameters did not offer any obvious advantage over the Lipinski Rule of 5 parameters.