Scientific pharmacophore-based

Holtje, H.-D. (1992) Pharmacophore identification based on molecular electrostatic potentials. In Wermuth, C.G., Koga, N., Koenig, H. and Metcalf, B. (eds). Medicinal Chemistry for the 21st Century, pp. 181-189. Blackwell Scientific, Oxford. 

A further important option for ligand-based virtual screening is to perform shape comparisons that have a pronounced scaffold hopping potential. An often used method of this kind is ROCS [31] (OpenEye Scientific Sofiware, 9 Bisbee Court Suite D, Santa Fe, NM 87508, USA. Available at http //www.eyesopen.com, March 20, 2009). ROCS employs continuous functions that are derived from atom-centered Gaussians to calculate the volume overlap between two 3D structures. The use of Gaussians drastically speeds up the computational process, and ROCS is able to search even databases with millions of compounds for molecules that can adopt shapes similar to the reference compound. As in the case of 3D pharmacophore searches, the low-energy conformations must be precomputed for the search database. 

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