Application of Molecular Topological Descriptors for Clustering a Database of Isothiourea Derivatives in Studying Structure – Activity Relationships

Resumo

A database of some S,N,N,N′-tetrasubstituted isothiourea derivatives possessing neuroprotective properties was successfully clustered in order to study the quantitative structure – activity relationship. Clustering by k-means was carried out in the factor space of topological descriptors. The identified clusters were combined according to analyses of intra- and intercluster distances. The initial number of clusters in the k-means clustering was determined from the number of iterations for which a solution was obtained. The homogeneity of the database and the identified clusters was estimated by using a coefficient of molecular diversity. A plot of the database compounds as points in factor space led to a conclusion about the successful applicability of the proposed clustering approach.