Identification of novel farnesyl protein transferase inhibitors using three-dimensional database searching methods

Generation of a three-dimensional pharmacophore model (hypothesis) that correlates the biological activity of a series of farnesyl protein transferase (FPT) inhibitors, exemplified by the prototype 1-(4-pyridylacetyl)- 4-(8-chloro-5,6-dihydro-11H-benzo [5,6]cyclohepta[1,2-b]pyridin-11-ylidene)piperidine, Sch 44342, 1, with their chemical structure was accomplished using the three-dimensional quantitative structure-activity relationship (3D-QSAR) software program, Catalyst. On the basis of the in vitro FPT inhibitory activity of a training set of compounds, a five-feature hypothesis containing four hydrophobic and one hydrogen bond acceptor region was generated. Using this hypothesis as a three-dimensional query to search our corporate database identified 718 compounds (hits). Determination of the in vitro FPT inhibitory activity using available compounds from this "hitlist" identified five compounds, representing three structurally novel classes, that exhibited in vitro FPT inhibitory activity, IC50 < or = 5 microM. From these three classes, a series of substituted dihydrobenzothiophenes was selected for further structure-FPT inhibitory activity relationship studies. The results from these studies is discussed.