This work presents two new topological indices, C(u) and C A(u), that permit their application to organic molecules containing oxygen, nitrogen, sulfur and halogens. These indices are obtained by modifying Schultz molecular topological index (2-MTI) and are validated by correlating the inhibitory activity of a group of diphenyl sulfone derivatives (SU). The proposed indices show that: 000a.- The use of two types of distance matrices to calculate the proposed indices does not produce significant differences in the calculated biological activity values obtained by using the corresponding regression equations. 000b.- In a set of nineteen 4-amino-4'-substituted diphenylsulfones, the new index C(u) permits to differentiate between two SU subsets by correlating it with the biological activity of these derivatives . 000c.- By applying the C(u) index to the set of the nineteen-4-aminodiphenylsulfone derivatives and to a subset of fourteen of them, it is possible to demonstrate that the correlation of biological activity with this index is in both cases better than the original Schultz index and the Kier chemical connectivity index (chi1V) order-1 valence type