Chemical graphs hydrogen-suppressed

Fig. 1. An example of two hydrogen-suppressed graphs G1 G2 and a common substructure CSIG,, G2) and the maximum common substructure MCS(G1 G2) are shown above. The Tanimoto similarity index and the distance between the two chemical graphs are computed below.

The approach used in chemical graph theory is to abstract from the molecular structure those elements that lead to structure variables in the form of numerical indexes. The set of atoms and connections is viewed as structure information but in a form not amenable directly to QSAR analysis. The first step is to adopt a form for the molecular skeleton as the basis for extraction of structure information. To represent the molecular skeleton, the hydrogen-suppressed graph is most commonly used hydrogen atoms are not explicitly considered hydrogen atoms are incorporated in skeletal groups which are the graph vertexes. 

The chemical graph theoretic hydrogen-suppressed connectivity matrix of ethane is ... 

In the Daylight software the 2-D chemical structure of a molecule is represented by a SMILES (Simplified Molecular Input Line Entry System) string derived from the hydrogen-suppressed graph of the molecule . The MODSMI operations, the subject of this report, essentially involve ... 

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