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Statistical Molecular Design, part 1 PDF Print E-mail
Written by Lennart Eriksson, Per M Andersson, Erik Johansson and Torbjörn Lundstedt   
In pharmaceutical industry one important goal is to identify new chemical entities (NCE), which have the potential for becoming approved drugs. Quantitative structure-activity relationship (QSAR) modeling is one efficient tool in this exercise. QSARs provide a rational basis for understanding mechanisms of biological and pharmacological performance and how to alter chemical structures to achieve improved performance.
However, in the quest for accomplishing a valid and reliable QSAR model, several critical stages will be encountered that have to be dealt with in a proper manner. Chemometric techniques are very purposeful in modern QSAR analysis and will help the inexperienced QSAR analyst avoiding the most trivial mistakes. The chemometric QSAR strategy, applicable both in drug design and environmentally related sciences, highlights some of the most crucial steps. These steps involve
· how to design the training set,
· how to account for chemical and biological properties of compounds,
· how to relate these to each other, and
· how to finally validate the relevance of an established QSAR model.
To accomplish a QSAR model of good predictive power, it is mandatory to have a sufficiently informative training set. It is difficult to create an informative set by a random or an arbitrary selection of compounds. An efficient selection strategy is clearly warranted. In this first episode of our five-fold editorial we will review and illustrate the concept of statistical molecular design (SMD). We will show how this methodology can be applied in QSAR modelling and combinatorial technologies to enable informative sets of molecules, substituents and building blocks.
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