Privileged pharmacophores

To account for the privileged substructures, one of the four pharmacophore points is forced to be a feature associated with the privileged substructure. In practice, this feature is a dummy atom deflned as the centroid of the substructure. Then, privileged pharmacophore keys are 4-point pharmacophore keys, where only pharmacophores including the dummy atom representing the substructure of interest are stored. 

Mason JS, Morize 1, Menard PR, Cheney DL, Hulme C, Labaudiniere RF. New 4-point pharmacophore method for molecular similarity and diversity applications Overview of the method and applications, including a novel approach to the design of combinatorial libraries containing privileged substructures. I Med Chem 1999 42 3251-64. 

Mason JS, Morize I, Menard PR, Cheney DL, Huhne C, Labaudiniere RF. (1999) New 4-Point Pharmacophore Method for Molecular Similarity and Diversity Appheations Overview of the Method and Applications, including a Novel Approach to the Design of Combinatorial Libraries Containing Privileged Substructures. J. Med. Chem. 42 3251-3264. 

Fig. 1.11. Privileged GPCR pharmacophore library (reprinted ( adapted or in part ) with permission from Journal of the American Chemical Society. Copyright 2003 American Chemical Society).

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