Toward the Rational Design of Sustainable Hair Dyes Using Cheminformatics Approaches: Step 1. Database Development and Analysis
Tova N. Williams, Melaine A. Kuenemann, George A. Van Den Driessche, Antony J. Williams, Denis Fourches , and Harold S. Freeman
Herein, we report on the initial step of the design process of new hair dyes with the desired properties. The first step is dedicated to the development of the largest, publicly available database of hair dye substances (containing temporary and semipermanent hair dyes as well as permanent hair dye precursors) used in commercial hair dye formulations. The database was utilized to perform a cheminformatics study assessing the computed physicochemical properties of the different hair dye substances, especially within each cluster of structurally similar dyes. The various substances could be differentiated based on their average molecular weight, hydrophobicity, topological polar surface area, and number of hydrogen bond acceptors, with some overlap also observed. In particular, we found that dyes such as C.I. Basic Orange 1 and 2 were clustered among the precursors, suggesting that their diffusion behavior is similar to that of permanent hair dye precursors. We anticipate taking advantage of this interesting knowledge in the second design phase of our investigation. As a step in that direction, we used QSAR models and noted that 65% of the substances were predicted to be mutagenic (22 with confidence thresholds >90%), whereas 79% were predicted to be skin sensitizers (37 with confidence thresholds >90%). We discuss the relevance of these preliminary calculations in view of literature-extracted experimental data.
The full text appears in the ACS Sustainable Chemistry and Engineering journal (DOI: 10.1021/acssuschemeng.7b03795)
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