A nice blog post describing the use of Torch to analyse molecules

The choice of which molecule(s) to progress into synthetic chemistry depends on a number of properties – potential for activity, logP, MW, flexibility etc.. The problem faced by most project teams is one of balance in that although there is usually an ideal range of values for each property, not every property is equally important. For example, the ideal may be to have MW<500 and logP<3 but there may be more tolerance for a high MW if logP is well within range.