Identify Chemical Molecules 

A SMILES string is a way to represent a 2D molecular graph as a 1D string. Find a way to determine if two SMILES strings have the same structure.

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X sm1 = "CN1C=NC2=C1C(=O)N(C)C(=O2)N2C"; sm2 = "CN2C(=O)N(C)C(=O)C1=C2N=CN1C";

Build the graphs from SMILES.

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X s = ImportString /@ {sm1, sm2};

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X e = First["EdgeRules" /. #] & /@ s; v = First["VertexTypes" /. #] & /@ s;

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X {g1, g2} = MapThread[ Graph[#1, VertexLabels -> Thread[Range[Length[#2]] -> #2], DirectedEdges -> False] &, {e, v}]

Out[4]=

The SMILES have different structures.

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X CanonicalGraph[g1] == CanonicalGraph[g2]

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