Distance screens

Jakes SE, Willett P. Pharmacophoric pattern matching in files of 3-D chemical structures selection of inter-atomic distance screens. / Mol Graph 1986 4 12-20. 

Jakes, S.E. and Willett, P., Pharmacophoric Pattern Matching in Files of 3-D Chemical Structures Selection of Inter-atomic Distance Screens, J. Molec. Graphics, 5, 49, 1986. 

The work at CAS has used conventional interatomic distance and valence and torsion angle screens, as well as the partially bonded angular screens described by Bartlett et al. (75) (vide infra), and a novel class of distance screens, which are based on information that can be calculated from triangles, that is, sets of three nonhydrogen atoms and the three corresponding inter-... 

SELECTION OF DISTANCE SCREENS FOR PHARMACOPHORIC PATTERN MATCHING... 

S. E. Jakes and P. Willett,/. Mol. Graphics, 4,12 (1986). Pharmacophoric Pattern Matching in Files of Three-Dimensional Chemical Structures. Selection of Interatomic Distance Screens. 

An alternative approach to the explicit storage of multiple conformations is the use of 3D distance screens. The ChemDBS-3D program provides a good example of such a technique and deals with the problem of conformational flexibility in the following manner ... 

The screen set procedures studied here are part of an ongoing project to investigate the use of angular information for 3-D substructure searching work in the future will seek to extend the present bond angle screens to include torsion angle data and to compare the retrieval capabilities of angular and distance screens. 

The molecules in these data-sets were then characterised by the presence or absence of the screens that are used for substructure searching in SOCRATES, the Pfizer Central Research chemical and biological databank system . In the case of the 2-D structures, there were 1315 atom-centred, bond-centred and atom sequence fragment screens in the case of the 3-D structures, there were 1471 inter-atomic distance screens. ... 

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