On the basis of the previous models of inductive and steric effects, 'inductive' electronegativity and molecular capacitance, a range of new 'inductive' QSAR descriptors has been derived. These molecular parameters are easily accessible from electronegativities and covalent radii of the constituent atoms and interatomic distances and can reflect a variety of aspects of intra- and intermolecular interactions. Using 34 'inductive' QSAR descriptors alone we have been able to achieve 93% correct separation of compounds with- and without antibacterial activity ( in the set of 657). The elaborated QSAR model based on the Artificial Neural Networks approach has been extensively validated and has confidently assigned antibacterial character to a number of trial antibiotics from the literature.