Substructure mappings

Fig. 15.8. Substructure mapping, highlighting, and drill-down. Based on on-the-fly substructure query and mapping capability within SciTegic Pipeline Pilot, PGVL Hub allows user to perform substructure queries into a set of target molecules. In the example shown, a set of substructure queries globally collected and validated as undesirable substructure features to be avoided are mapped into target molecules (41b).

Gq is a substructure of Gp (i.e., Gq is isomorphic with a subgraph of Gp) if and only if all the atoms of Gq can be mapped onto a subset of atoms of Gp in such a way that the bonds of Gq map the corresponding bonds which connect the mapped atoms fi om Gp Each mapping between Gq and Gxcan be considered as a function... 

To obtain an effective algorithm for substructure searching the factorial degree of the brute force algorithm has to be drastically deaeased. In the next sections we discuss several approaches where combination leads to a much more effective and apphcable approach for substructure searching. In the process of searching the isomorphism between Gq and a substructure of Gx, the partial mappings Gq —> Gj can be used as well. In these cases, not all atoms from Gq are mapped and, for those which are not, the array value Mj is set to 0. 

Fig. 12. (see opposite page) The library enumeration interface (A) allows for up to three reactant files to be uploaded. This is also where the preference for how to handled reactants that map multiple times to the substructure as defined in the RXN file is set. These compounds can be rejected, reacted once, or they can be reacted at each matching site. The output of the library subset (B) can be visualized in a web page before downloading the entire library. 

To elucidate the contribution of the different histological structures to the average Raman spectral signatures from intact pollen grains, we conducted spatially resolved measurements on sections of rye pollen grains. Such mapping experiments can help separation of predominant spectral contributions from different substructures. 

For drawing similar molecules in a similar way, the Feature Tree comparisons are useful as they detect similarity beyond mere substructure identity and they also provide a mapping that can be viewed as alignments of molecule fragment pairs. 

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