Eccentric Distance Sum
Chemical graphs, particularly molecular graphs, are models of molecules in which atoms are represented by vertices and chemical bonds by edges of a graph. A graph invariant is any function calculated on a molecular graph irrespective of the labeling of its vertices. The values of the eccentric distance sum of each analog in the data set were computed and active range identified. Subsequently, biological activity was assigned to each analog in the data set, which was then compared with the reported anti-HIV activity of dihydroseselin analogs. Excellent correlations were obtained using the eccentric distance sum in all six data sets employed in Gupta et al. Correlation percentages ranging from 93% to more than 99% were obtained in data sets using eccentric distance sum. The eccentric distance sum has attracted a lot of interest in the last several years both in mathematical and chemical research communities, and numerous results and structural properties of the EDS were established.