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■Bio-mathematics, Statistics and Nano-Technologies: Mosquito Control Strategies
Figure 9.7: The distribution of the compounds on the score plot based on their physico-
chemical properties.
in the literature (Héberger, 2010; Kollár-Hunek and Héberger, 2011; Kollár-Hunek and
Héberger, 2013). The practical application of SRD method in the ranking of compounds
based on their physicochemical descriptors is demonstrated on the aforementioned set of
natural and synthetic compounds with repellent activity towards A. gambiae females.
The results of the SRD analysis are presented in Figure 9.8. The reference ranking was
the row average of the normalized values of molecular descriptors. The results indicate
that ethyl cinnamate and benzyl benzoate are the closest to the average ranking, while the
compound Syn12 is placed furthest from it. This means that Syn12 may have significantly
different molecular features than other compounds from the same set. This does not nec-
essarily mean that the Syn12 compound has the weakest repellent activity but it possess
extreme lipophilicity, boiling point, melting point, critical temperature and other molecular
features. The SRD approach is quite useful in quick detection of compounds with extreme
molecular properties based on the established reference ranking.
Considering the similarities between the ranking numbers of different compounds, the
SRD approach can be used for the analysis of the grouping of similar compounds in the
space of selected molecular properties. For example, in Figure 9.8 it can be seen that