Generic Structures Reduced

Fig. 3.8 Typical generic structures selected for the reduced complexity screening set.

Figure 4, A generic structure and the two forms of reduced chemical graphs describing it.

The size and complexity of generic structures leads to the requirement for more elaborate screening systems than for specific structures. The different approaches which have been implemented at Sheffield include fragment and ring screens and also reduced graphs of var3dng discriminatory power. 

Figure 4. The GENSAL, ECTR and ring/non-ring reduced graph representations of a generic structure...

Fig. 5. Comparison of ab initio, DFT/BPW91/6-31G -computed IR and VCD spectra over the amide I, II, and III regions for model peptides (of the generic sequence Ac-Alaw-NHCH3). These are designed to reproduce the major structural features of an o -helix (top left, n— 6, in which the center residue is fully H-bonded), a 3i helix (PLP Il-like, top right, n— 4), and an antiparallel /1-sheet (n= 2, 3 strands, central residue fully H-bonded) in planar (bottom left) and twisted (bottom right) conformations. The computations also encompass all the other vibrations in these molecules, but those from the CH3 side chains were shifted by H/D exchange (CH3) to reduce interference with the amide modes.

Gillet, V.J., Downs, G.M., Holliday, J.D., Lynch, M.F., Dethlefsen, W. Computer storage and retrieval of generic chemical structures in patents. 13. Reduced graph generation. Journal of Chemical Information and Computer Science 1991, 31, 260-270. 

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