The series consist of total 18 numbers of compounds with well defined monoamine oxidase-B inhibitory activity. The series (E)-3-Heteroarylidenechroman-4-ones as potent and selective monoamine oxidaseB inhibitors have been chosen for study. The IC5o values were chosen for generating common pharmacophore hypotheses and 3D- QSAR study. In the „Score Hypotheses? step, common pharmacophores were examined, and a scoring procedure was applied to identify the pharmacophore from the best alignment of the chosen actives and provided a ranking of the different hypotheses for the next step